Source contamination and tectonomagmatic signals of overlapping Early to Middle Miocene orogenic...

Lithos 140-141 (2012) 119ndash141

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Source contamination and tectonomagmatic signals of overlapping Early toMiddle Miocene orogenic magmas associated with shallow continental subductionand asthenospheric mantle flows in Western Anatolia A record from Simav(Kuumltahya) region

Hakan Ccediloban a Zekiye Karacık b Oumlmer Işık Ece b

a Suleyman Demirel University Department of Geological Engineering 32260 Cunur Isparta Turkeyb Istanbul Technical University Faculty of Mines Department of Geological Sciences Maslak 34469 Istanbul Turkey

Corresponding authorE-mail addresses cobanmmfsduedutr hakancoba

zkaracikituedutr (Z Karacık) eceituedutr (OumlI Ece

0024-4937$ ndash see front matter copy 2011 Elsevier BV Alldoi101016jlithos201112006

a b s t r a c t

a r t i c l e i n f o

Article historyReceived 18 April 2011Accepted 15 December 2011Available online 21 December 2011

KeywordsPotassic magmasMantle flowTrench retreatShallow continental subductionCrustal delaminationWestern Anatolia

The disappearances of mafic shoshonitic and ultrapotassic magma prior to Late Oligocene in Western Anato-lia post-collisional tectonic settings and the sudden appearance of Early-Middle Miocene potassic lavas withorogenic geochemical signatures indicate a striking change of mantle sources during the Early-Middle Mio-cene period and require a special explanation In this regard the Simav (Kuumltahya) region of Western Anatoliarepresents a critical area where the Early-Middle Miocene mafic potassic (shoshonite absarokite ultrapotas-sic) and high-K calc-alkaline (andesite dacite-rhyolite granite) series rocks overlap in the extensional geo-tectonic setting in a back-arc position The appraisal of petrological data obtained from Simav igneouscomplex indicates that there is a remarkable geochemical and isotopic similarity (eg negative Eu anomaliesNbndashTa depletions high Sr low Nd and variable Pb isotope compositions) between coevally generated maficpotassic and high-K calc-alkaline magma series The near primitive mafic potassic (MHKS) lavas with high Srisotope compositions require a heterogeneous mantle source contaminated with crustal materials Draggedand delaminated crustal components caused by shallow continental subduction and the late arrived sub-ducted terrigenous sediments from the Aegean trench are likely candidate sources of continental materialsincorporated into the mantle source of the Simav mafic potassic (MHKS) magmas The nature of these com-ponents also played a significant role in the compositional variations of Simav mafic series rocks The Simavmafic potassic (MHKS) magmas were derived from a crust-contaminated subduction-modified (metasoma-tized) EM-II type mantle source interacting with influxed asthenosphere in a back-arc mantle wedge where-as mixing of lower crustal silicic melts with underplated potassic mafic magmas resulted in coeval high-Kcalc-alkaline rocks matched by the extent of crustal contamination observed in the more evolved silicicrocks The petrogenesis of the Simav magmatism was triggered by multiple driving forces with kinematiclinkage such as asthenospheric mantle flows trench retreat shallow continental subduction regional exten-sional uplifting (eg Menderes Massif) and concomitant extension and delaminations of subducted (accret-ed) crust and mantle lithosphere Considering the Late Tertiary geodynamic picture of the Western Anatoliaback-arc extensional province the initiation of post-collisional potassic and ultrapotassic magma pulses as atectonomagmatic precursor provide evidence for (i) the timing of last stage of regional uplifting (eg Men-deres Massif) and onset of extensional basin formations in different periods and (ii) rapid tectonictransitions

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1 Introduction

Potassic calk-alkaline magmas are mostly accompanied by maficpotassic magmas in post-orogenic intra-plate settings (eg Agostiniet al 2010 Avanzinelli et al 2009 Benito et al 1999 Boari et al2009b Conticelli et al 2009a 2009b Frezzotti et al 2007

nsduedutr (H Ccediloban))

rights reserved

Peccerillo 2005 Pe-Piper and Piper 2001 2007) Such magmatic pat-terns are commonly observed in the Early-Late Tertiary of the Medi-terranean and surrounding region (eg Spain and southern IberiaBenito et al 1999 Duggen et al 2005 Italy Avanzinelli et al2009 Boari et al 2009b Conticelli et al 2009a 2009b Frezzotti etal 2007 Pannonian basin Harangi et al 2006) In this regard theWestern Anatolia Extensional Province (WAEP) is a good exampleof the processes associated with tensional tectonics and associated al-kaline and calk-alkaline magmatic pulses in the Mediterranean post-orogenic setting (eg Agostini et al 2010 Akay and Erdoğan 2004

120 H Ccediloban et al Lithos 140-141 (2012) 119ndash141

Aldanmaz et al 2000 Innocenti et al 2005 Pe-Piper and Piper 20012007 Seyitoğlu et al 1997) Following Late Cretaceous to Early Eo-cene compressive deformation along with propagating diverse geo-dynamic processes such as asthenospheric mantle flows trench-retreat roll-back of the Aegean slab regional uplift (exhumation ofthe Menderes Massif) and extensional tectonic the WAEP hosted dis-tinct (low-K to high-K calc-alkaline and medium-K to high-K alka-line) magma series (eg Agostini et al 2007 2010 Akay 2008Altunkaynak and Genccedil 2008 Ersoy et al 2008 Innocenti et al2005 Pe-Piper and Piper 2001 2007) In contrast to the subalkalineand transitional affinity of magmatism during Middle EocenendashLateOligocene time (eg Altunkaynak and Genccedil 2008 Ercan et al1995 Karacık et al 2007 2008 Koumlpruumlbaşı and Aldanmaz 2004)the Early to Middle Miocene period is characterized by the appear-ance of almost contemporaneous mafic potassic and high-K calc-alkaline magmas in a post-collisional intra-plate (back-arc) exten-sional setting In this geodynamic setting mantle heterogeneity andthe nature of mantle sources also require a particular interest

Here we focus on the Simav (Kuumltahya) mdash Uşak region of WesternAnatolia where mafic and intermediate-silicic members of Early-Middle Miocene mafic potassic and high-K calc-alkaline magmaswere formed contemporaneously in the same tensional tectonic envi-ronment Volcanic and plutonic rocks around the Simav graben pro-vide some data critical to the understanding of the evolution of thegeotectonic environment and magmatic patterns (eg intra-plate po-tassic magmas) of the Aegean region Since the Simav mafic potassicvolcanic rocks represent rather primitive mantle-derivedmelts a pet-rological study of the Simav magmatism may also provide useful in-formation for better understanding of the geodynamic processesassociated with a back-arc setting Here we document systematic re-search on KndashAr chronology geochemistry and particularly Sr Ndand Pb isotope compositions of Early to Middle Miocene magmaticrocks in the Simav region to explain how coevally generated maficpotassic and high-K calc-alkaline (post-collisional) magma pulsesoccur in the same geodynamic tectonic setting We also provide con-straints on the tectono-magmatic setting and compositional charac-teristics of strongly potassic magmas

2 Geological background

Structural magmatic and metamorphic records from Simav andsurrounding regions in the seismically active Western Anatolia(back-arc) extensional province have been reported by severalworkers during the last decade (eg Akay 2008 Bozkurt andSoumlzbilir 2004 Ersoy et al 2008 2010 Hasoumlzbek et al 2010Innocenti et al 2005 Işık et al 2003 2004 Karaoğlu et al 2010Purvis and Robertson 2004 Ring and Collins 2005 Seyitoğlu 1997Seyitoğlu et al 1997 2004 Thomson and Ring 2006)

The Simav region in Central Western Anatolia is located betweenthe İzmir-Ankara Neotethyan suture zone to the north (Şengoumlr andYilmaz 1981) and the Taurides (Lycian Nappes) to the south (egCollins and Robertson 1999) (Fig 1) Basement rocks in the regionare represented by several rock groups of the Menderes Massif andthe Afyon zone (Akdeniz and Konak 1979) (Fig 1) The MenderesMassif is a NEndashSW trending large-scale dome-shaped metamorphiccore complex interpreted as the eastward continuation of the Cyclad-ic Massif in the Aegean Sea (eg Oberhaumlnsli et al 1997) The Mende-res block collided with Sakarya prior to 50 Ma ago followed byregional high-temperature (HT) metamorphism and granitic intru-sions (van Hinsbergen et al 2010b) The exhumation of the Mende-res Massif occurred along the successive detachment faults duringthe Neogene period Recent studies show that the Menderes Massifhas experienced a two- or multi-stage exhumation process (Lips etal 2001 Seyitoğlu et al 2004) The first stage of exhumation of theMenderes Massif occurred between the late Oligocene (25 Ma) andthe Middle Miocene (16 Ma) (Seyitoğlu et al 2004) perhaps chiefly

in the latest Oligocene (Purvis and Robertson 2005) or in latest Oli-gocene to earliest Miocene time (eg Cavazza et al 2009) Agostiniet al (2010) interpreted the uplifting and exhumation of the Mende-res Massif basement rocks as a consequences of extensional grabensand transtrensional fault systems Accordingly Bozkurt et al (2011)suggested the beginning of extensional exhumation of the northernMenderes Massif during Late Oligocene (30 Ma) Cavazza et al(2011) proposed that extension affecting the Aegean region gaverise to exhumation at a regional scale Some studies also suggestthat there are apparent links i) between Early-Middle Miocene exten-sion and roll-back of the Aegean trench and ii) Late MiocenendashPlio-Quaternary extension and the onset of the roll-back of the subductedAegean slab in Western Anatolia (eg Burchfiel et al 2008Dumurdzanov et al 2005 Papanikolau 2010 Royden andPapanikolaou 2011) The timing and cause of extension of the Aegeangrabens are discussed by Bozkurt and Soumlzbilir (2004 and referencesthere in) Ersoy et al (2010) van Hinsbergen (2010) and vanHinsbergen et al (2010a 2010b)

Three main EndashW trending grabens which are called the SimavGediz and Buumlyuumlk Menderes grabens divide the Menderes Massifinto subunits (Fig 1) Tectonic evolution of the graben-type basinsin Western Anatolia was governed by episodic (eg Bozkurt 20002001 2003 Ersoy et al 2010 Koccedilyiğit et al 1999) or pulsed exten-sional forces (Bozcu 2010 Purvis and Robertson 2004 2005) duringthe late Cenozoic These basins host intraplate (post-collisional)magmas

The Simav graben is a PliocenendashQuaternary structure with a dis-tinct topographical depression extending for about 150 km (Fig 2)The graben cuts the NEndashSW trending Demirci Selendi and Akdere ba-sins and is regarded as one of the latest products of NndashS extensionaltectonics in contrast to the Aegean grabens that began to developduring late OligocenendashEarly Miocene times (Seyitoğlu et al 1997)The southern side of the Simav half-graben cut the Neogene basinsand also the Simav detachment fault Bozkurt et al (2011) suggestedan episodic Simav detachment fault activity between ca 30 and 8 MaBased on the age of the granitoids and the mylonitic deformation ofthe Eğrigoumlz granitoid some workers (Işık and Tekeli 2001 Işık etal 2004 Ring and Collins 2005 Thomson and Ring 2006) suggestedthat the extensional tectonics of Western Anatolia began before EarlyMiocene times and represents an early stage in the Tertiary exten-sional tectonics of Western Turkey Cavazza et al (2009) suggestedthat the Neogene extensional tectonism in the northern Aegean re-gion has been episodic with accelerated pulses in the Early-MiddleMiocene and Plio-Quaternary

Sedimentation in the basins began with fluvial conglomerates andcontinued with approximately 200 m of fluvial sediments and lime-stones which alternate with volcanic products upwards in the section(Akdeniz and Konak 1979 Ercan et al 1982 Ersoy et al 2010)(Fig 2) The age of the sediments is accepted to be early Mioceneon the basis of radiometric age data (ranging between 242 Ma and149 Ma) from the volcanic intercalations (eg Ercan et al 1996Ersoy et al 2011 Purvis and Robertson 2004 2005 Seyitoğlu et al1997) Ersoy et al (2010) indicated that the crustal extensionresulted in the exhumation of the mid-crustal units (the MenderesMassif) synchronously with volcano-sedimentary basin formation

As summary the occurrence of volcanic rocks intercalated withsediments in graben-type structures and extensional uplifting ofthe region shows that (Early to Middle Miocene) magmatism inSimav region took place under an extensional tectonic regime in aback-arc position

3 Analytical methods

Approximately 70 rock samples were collected from representa-tive sections of all magmatic units in the study area during fieldworkThin sections of these rock samples were prepared in the Istanbul

Fig 1 Main tectonic and geological units of western Anatolia from Yılmaz et al (2000) IASZ İzmir-Ankara Suture Zone SG Simav graben GDG Gediz graben BMG Buumlyuumlk Men-deres graben

121H Ccediloban et al Lithos 140-141 (2012) 119ndash141

Technical University laboratory A selection of 43 fresh sampleswhich represent all rock types (5 samples of Naşa basalt 9 samplesof Payamtepe basic volcanics 18 samples of andesite dacite-rhyolitelavas mdash Karaboldere silicic volcanics 11 samples of Koyunoba andEğrigoumlz granites and their xenoliths and 2 gneiss samples from Men-deres Metamorphics) were analyzed for major trace and rare-earthelements using the ICP-OES method in ACME Analytical Laboratory(Canada) The detection limit of this method for major oxides ranges

from 004 to 001 REEs and trace elements were analyzed using ICP-MS with a detection limit for REEs of b0001 ppm Characteristic min-eral compositions in igneous rocks from various units were analyzedon polished sections using the JEOL 8600 electron microprobe at theUniversity of Georgia USA Natural and synthetic mineral standardswere used for WDA electron microprobe analyses with analyticalconditions of 15 kV and 15 mA Element abundances were correctedwith the PRZ matrix correction software In addition 19 samples

Fig 2 Simplified geological map of the Simav and surrounding region modified from Seyitoğlu (1997)


were selected from different representative units for Sr Nd and Pbisotope studies which were done on a fully automated thermal ioni-zation mass spectrometer (VG Sector 54) at the University of NorthCarolina Chapel Hill USA Separated minerals (amphibole and bio-tite) from nine samples and two whole-rock samples were dated bythe conventional KndashAr method at Georgia State University USA

4 Spatio-temporal evolution of Simav (post-collisional) magmatism

Previous and new geochronological studies (Table 1 Fig 3) on theSimav igneous complex and neighboring provinces (eg Bingoumll et al1982 Erkuumll et al 2005 Ersoy et al 2008 Hasoumlzbek et al 2010 Işık etal 2004 Innocenti et al 2005 Karaoğlu et al 2010 Karaoğlu et al2010 Ring and Collins 2005 Seyitoğlu et al 1997 Westaway et al2004 this work) clearly define two distinct periods of (post-collisional)extension-related magma generation I) Late Oligocene to Early-MiddleMiocene (249ndash125 Ma) and II) Late MiocenendashPliocene-Quaternary(b85 Ma) New KndashAr age determinations confirm that the plutonics(known as Koyunoba and Eğrigoumlz granites) intermediate to silicic volca-nics (andesite and dacites called Karaboldere volcanics) andmafic volca-nic rocks (shoshonitic-absarokitic and ultrapotassics called Naşa andPayamtepe volcanics) around the Simav region belong to the first periodof magmatism (Table 1 Fig 3) Radiometric ages show that themafic po-tassic and high-K calc-alkaline magma pulses occurred almost contem-poraneously during Early to Middle Miocene time Dating of calc-alkaline intermediate-silicic volcanic phases gives ages of 228ndash168 Ma

Table 1KndashAr radiometric age determinations for Simav magmatic complex

Sampleno

Rock type Material Mass fraction potassium(as K) (dagkg)a

40 Dacite Mica 687plusmn00713-a Dacite Mica 250plusmn003d-63 Dacite Mica 708plusmn007d-61 Dacite Mica 714plusmn00738 Dacite Mica 686plusmn00812 Andesite Amphibole 047plusmn00113b Andesite Mica 629plusmn00629 Granite Mica 710plusmn00714 Ultrapotassic Whole-rock 413plusmn004so7-15 Ultrapotassic Whole-rock 507plusmn005

for andesites and 207ndash125 Ma for dacites (Table 1) The crystallizationcooling and exhumation history of the Eğrigoumlz and Koyunoba granitesspans the period 228ndash194 Ma (Hasoumlzbek et al 2010 Işık et al 2004Ring and Collins 2005 and this work) Dating of the mafic phases(Table 1) gives ages of 205ndash153 Ma (Early-Middle Miocene Ercan etal 1996 Erkuumll et al 2005) for medium-K shoshonitic rocks and186ndash142 Ma (Early-Middle Miocene Ersoy et al 2008 Innocenti etal 2005 Seyitoğlu et al 1997 this work) for ultrapotassic (lamproiticRoman Province-like) eruptions The second (Late Miocene to Plio-Quaternary) period in adjacent provinces is characterized by the eruptionof Kabaklar basalts (85ndash837 Ma Ersoy et al 2008) and Plio-QuaternaryKula basalts (Westaway et al 2004)

5 Classification and petrography

Major element data from the Simav Early-Middle Miocene mag-matic rocks are summarized in Table 2 recalculated to 100 on an an-hydrous basis The compositions of the analyzed mafic series rocksplot as trachybasalt basaltic trachyandesite and phonotephrite on atotal alkali (K2O+Na2O) vs SiO2 diagram (Fig 4a) and within theshoshonite absarokite and ultrapotassic fields on a K2O vs SiO2 dia-gram (Peccerillo and Taylor 1976 Fig 4b) According to the definitionof Foley et al (1987 not shown in the figure) the Simav ultrapotassicrocks would be classified as Roman Province Type The intermediateand silicic series rocks plot in the andesite trachyandesite trachyda-cite dacite and rhyolite fields and the plutonics in the rhyolite areas

Mass fraction potassium(as K2O) (dagkg)a

Radiogenic argon Apparentage (Ma)

()b (nmolkg)

828plusmn008 53 236plusmn4 197plusmn06301plusmn003 62 69plusmn1 159plusmn05853plusmn009 84 256plusmn3 207plusmn05860plusmn009 91 255plusmn3 205plusmn05827plusmn008 78 232plusmn3 194plusmn05057plusmn001 57 19plusmn1 228plusmn10758plusmn008 81 208plusmn3 190plusmn05856plusmn009 86 255plusmn3 206plusmn05497plusmn005 68 115plusmn6 160plusmn08611plusmn006 74 138plusmn2 157plusmn05

Fig 3 Chronological relationships between alkaline and calc-alkaline magmatic activities in Simav and surrounding regions CAV high-K calc-alkaline volcanics CAG high-K calc-alkaline granites Data source Bingoumll et al 1982 Erkuumll et al 2005 Ersoy et al 2008 Hasoumlzbek et al 2010 Işık et al 2004 Innocenti et al 2005 Karaoğlu et al 2010 Ring andCollins 2005 Seyitoğlu et al 1997 Westaway et al 2004 this work


on the TAS (total alkali-silica) variation diagram (Fig 4a) They areclassified as high-K calc-alkaline series rocks (Fig 4c) K2O contentsof the mafic series rocks show a regular trend from absarokite-shoshonites to ultrapotassic rocks Here we refer this mafic groupas the MHKS (moderate-high potassium absarokite-shoshonite andultrapotassic) mafic series

The mineralogical assemblage of the calc-alkaline granite-granodiorites (Koyunoba and Eğrigoumlz Plutons) comprises alkali feld-spar (orthoclase-perthite) plagioclase (An13ndash32 albite-oligoclase-andesine) quartz biotite and hornblende Sphene apatite rutilezircon zoisite magnetite ilmenite and pyrite are present as accessoryminerals They also contain biotite- plagioclase- and alkali feldspar-bearing mafic micro-granular dioritic enclaves and are cut by apliticand pegmatitic dikes The Karaboldere silicic volcanics (andesitedacite rhyoliterhyodacite and subordinate obsidian flows) are asso-ciated with pyroclastic deposits Plagioclase (An60ndash85) clinopyroxene(Wo36ndash44-Ens42ndash56) and rarely orthopyroxene (Ens80ndash94) crystals areobserved as phenocrysts and microphenocrysts in andesites Biotiteand hornblende occur rarely in these Corroded quartz twinned pla-gioclase (An32ndash61) and sanidine are the main phenocryst phases ofthe dacitic lavas The mafic Naşa and Payamtepe volcanics are repre-sented by shoshonitic (trachybasaltic-basaltic trachyandesitic) absaroki-tic and Roman Province Type (RPT) ultrapotassic lavas The Naşa basalt isa typical amygdaloidal basalt with microlitic and pilotaxitic texture Pla-gioclase (An53ndash62) pyroxene (Wo45ndash51-Ens50ndash54) and olivine (Fo55ndash76)are the main phenocryst phases Absarokites are characterized by abun-dant phenocrystals of pyroxene (Wo1ndash51-Ens40ndash72) altered olivine andmicrolitic groundmass feldspars RPL (Roman Province Lavas)-likeultrapotassic rocks crop out as isolated bodies scattered in theSimav region Common chlorite in micas and serpentine in olivines ap-pear as alteration products in feldspar-bearing leucite-free ultrapotas-sic lavas

6 Petrological characteristics of the Simav magmatic rocks

61 Geochemical and isotopic characteristics

On the basis of geochemical (major trace element REE) and SrndashNdndashPb isotopic data (Table 2) the Simav magmatics can be separated intotwo distinct groups i) a mafic group comprising mafic potassic (absar-okite-shoshonite) and ultrapotassic (MHKS) rocks (Naşa and Payam-tepe volcanics) and ii) a high-K calc-alkaline (intermediate-silicic)group including volcanic (Karaboldere andesite dacite and rhyolites)and plutonic rocks (Eğrigoumlz and Koyunoba granite-granodiorites) Se-lected major and trace element contents of the Simav mafic andhigh-K calc-alkaline magmatic rocks are plotted as a function ofMgO contents in Fig 5 together with previously published data

(Akay 2008 Erkuumll et al 2005 Innocenti et al 2005 Seyitoğlu etal 1997)

611 Mafic seriesThe Early-Middle Miocene Payamtepe and Naşamafic potassic lavas

of the Simav region show intermediate to high Cr Ni andMgO contents(Cr 68ndash322 ppm Ni 50ndash258 ppm and MgO 343ndash1013 wt) withgenerally higher values for ultrapotassic rocks than for potassic(shoshonite-absarokite) samples (Fig 5) reflecting near-primitive peri-dotitic mantle-derived magmas However lamproitic rocks in the re-gion have the most refractory nature (eg MgO 939ndash1069 wt Cr480ndash720 ppm Innocenti et al 2005) In general the Simavmafic seriesshows regular enrichments for major incompatible and rare-earth ele-ments from potassic (absarokite-shoshonites) to ultrapotassic lavasHigh-K ultrapotassic (MHKS) samples display generally higher concen-trations of all incompatible trace elements relative to absarokite-shoshonites with similar MgO contents although some overlap exists(Fig 5) Except for Rb enrichment and a wide range of Ba contents(~400ndash900 ppm) in the ultrapotassic rocks large ion lithophile ele-ments (LILE Th U light REE) show an overlap between potassic andultrapotassic rocks whereas high field strength elements (HFSE ZrHf Nb Ta etc) show an increase from potassic to ultrapotassic rocks

Relative to the OIB-like intra-plate Kula basalts (Alıcı et al 2002)from the neighboring province the Simav mafic series rocks demon-strate a clear enrichment in Rb Th U and Hf but are depleted in Nband Ta These mafic samples also display variably fractionated REEpatterns and varying degrees of light REE (LREE) enrichment withweak negative Eu anomalies (Fig 6a) MHKS samples show notice-able LREE enrichment relative to GLOSS (Global Subducting Sedi-ments Plank and Langmuir 1998) and upper crust (Fig 6a)Mantle-normalized incompatible element diagrams (Fig 6b) forEarly-Middle Miocene MHKS samples show Ta and Nb troughs posi-tive spikes for Ba Rb Cs Th U LREE and Pb (except for ultrapotassicrocks which display a wide dispersion) and negative spikes for Hf Zrand Ti The REE patterns of calc-alkaline silicic series rocks displaydeeper negative Eu anomalies than those of MHKS rocks (Fig 6c)Dacite REE patterns are similar to those of upper crust and significantheavy REE enrichment is observed in granitic xenoliths (Fig 6c)Mantle-normalized incompatible element diagrams of the mafic se-ries rocks are akin to those of calc-alkaline rocks except for excessenrichments of Th and U in granites and negative Ba and positiveRb anomalies (Fig 6d e) In contrast to those of the asthenosphericKula basalts showing typical OIB-like REE and incompatible elementpatterns (eg flat REE pattern absence of NbndashTa depletion see Alıcıet al 2002) all these characteristics of the Simav mafic series rocksare compatible with typical orogenic magmas

Relative to anorogenic magmas (eg Quaternary Kula lavas Alıcıet al 2002) generated from sublithospheric mantle Simav magmatic

Table 2Age (KndashAr Ma) geochemical (major wt trace and REE as ppm) and Sr Nd and Pb isotopic data for Simav igneous rocks Data for two samples from the Menderes metabasementsare also reported

KndashAr (Ma) Mafic series

160plusmn08 157plusmn05

Shoshonite Absarokite Ultrapotassic

Sample so7-3 So7-2a 1 2 so7-1 3 so7-11 14 so7-15 5 so7-8UTM Coordinates e671957 e674215 e676425 e673650 e674955 e672295 e613110 e666050 e697124 e666510 e697326

n4341555 n4336750 n4334765 n433705 n4333750 n433905 n4330765 n4347850 n4342452 n4353210 n4312165SiO2 5291 5453 5485 5452 5446 5005 4833 4792 5009 5274 4942TiO2 117 126 118 121 126 113 114 15 172 174 159Al2O3 1575 1605 1544 1517 1563 1571 1569 1226 1304 1306 1305Fe2O3 692 732 727 737 722 783 779 602 664 673 747MnO 013 011 014 014 012 013 013 01 008 007 01MgO 343 437 429 453 448 715 763 431 544 543 1013CaO 784 585 715 729 679 839 868 1258 829 718 664Na2O 301 285 307 286 277 266 273 216 208 212 229K2O 445 451 426 444 456 309 34 504 651 6 556P2O5 066 071 0645 0668 072 0509 059 0405 05 0509 078LOI 32 19 15 12 15 32 34 72 48 36 24Total 9947 9946 9979 9939 9951 9984 9951 9949 9919 9918 9943Sr 8009 6263 6724 667 7026 776 779 597 5136 505 666Ba 1319 1331 1210 1246 1350 957 1131 473 449 405 913Rb 1282 1397 1366 153 1479 881 1004 185 2815 273 1781Ni 63 80 552 51 58 89 106 783 114 1037 258Co 234 239 215 21 235 26 281 276 274 28 35Cr 68 103 171 185 103 253 137 273 171 322 239V 159 166 143 152 179 167 193 141 156 151 190Zr 4445 5148 430 453 5395 215 2536 433 4999 469 5332Y 329 393 314 31 366 242 279 212 224 217 233Nb 303 318 368 358 323 167 202 265 291 29 321Ga 175 188 174 181 184 144 168 181 186 187 167Hf 11 128 121 123 137 57 68 132 135 142 146Pb 49 54 38 4 57 37 41 11 08 08 15Ta 18 17 2 18 19 13 11 16 18 08 17Th 133 138 124 142 143 189 182 103 99 113 138U 42 42 4 43 47 45 53 42 44 44 49

REE (ppm)La 696 749 674 662 71 514 566 49 506 498 522Ce 1402 1428 1338 1305 1448 1011 1117 1024 1086 1086 108Pr 1652 1883 163 1607 1792 1206 1326 1393 1513 1479 1323Nd 607 701 58 556 662 475 486 555 616 591 479Sm 1024 1191 977 969 1125 816 866 949 972 967 806Eu 242 269 225 223 253 181 22 193 22 22 206Gd 787 956 717 683 871 583 689 5 642 526 608Dy 645 723 657 638 688 498 566 401 423 426 463Er 312 389 327 321 359 242 285 193 22 201 217Tb 118 14 123 121 129 091 105 088 089 088 09Ho 116 135 119 115 121 087 099 072 077 078 082Tm 05 056 052 046 054 036 042 029 031 029 03Yb 304 36 299 308 353 222 267 181 19 173 197Lu 047 051 049 048 051 032 039 026 028 028 029IsotopeSr87Sr86 0707693 0707644 0707979 0708125Nd143Nd144 0512372 0512379 0512398 0512383Pb206Pb204 1893691 18953 1904083 1906099Pb207Pb204 1570569 15721 1571306 1570682Pb208Pb204 3906858 39116 3913163 3912589

High-K calc-alkaline series

228plusmn1 190plusmn05 157plusmn05

Andesite Daciterhyolite


rocks have compositions typical of orogenic magmas generated fromsubduction-modified enriched (metasomatized) mantle lithospherewith or without asthenospheric influx (cf (Aldanmaz et al 2000))This is seen (Fig 7a b) for example using trace element criteriasuch as NbZrndashThZr and ThndashHfndashNb2 (eg Bianchini et al 2008Krmiacuteček et al 2011 Peccerillo 2005 Wilson and Bianchini 1999)In these variation diagrams Late Miocene basalts (Kabaklar basaltAgostini et al 2007 Ersoy et al 2008 Innocenti et al 2005) showa gradual transition between anorogenic Kula basalts and orogenicSimav rocks Accordingly in SrndashNd isotopic plots (see Fig 13) Late

Miocene basalts show a similar gradual transition between Early-Middle Miocene orogenic and Plio-Quaternary anorogenic typemagmas suggesting increasing input of asthenospheric material inthe back-arc mantle Orogenic magmas depleted in TiO2 Nb and Taand with high Sr isotopic ratio can be expected from the assimilationof subduction-modified lithospheric mantle by ascending astheno-spheric melts (OBrien et al 1995) Thus as shown in Figs 5 8abcand 11a the geochemical tendencies to anorogenic intra-platemagmas for the Simav MHKS rocks (particularly for ultrapotassicrocks) can be attributed to the introduction of intra-plate magmas

Table 2 (continued)




12 13-b 13-a Ar-3 d-51 d-55e611050 e609810 e611225 e624610 e625512 e627306n4328975 n4322620 n4325050 n4332520 n4336980 n43368805918 5717 6318 7907 7631 7023075 078 081 006 007 0361761 1697 1599 1117 1244 1455518 632 519 052 154 264006 011 004 001 003 003184 332 083 004 008 08255 674 396 049 06 186366 278 365 228 27 298344 298 364 519 534 4603 02 03 0011 0013 014521 23 21 09 05 19962 9967 9969 9974 9962 9921781 659 6393 445 433 2341540 1341 1642 182 178 88171 974 974 179 162 16453 84 48 18 39 2997 168 91 08 14 3327 205 14 615 48 14105 148 101 4 4 23176 162 177 862 879 166264 266 269 189 193 18412 104 126 122 124 14166 178 173 116 118 16848 48 55 36 34 52112 42 4 21 95 271 08 09 11 12 13264 175 225 282 333 20355 49 49 67 65 92

REE (ppm)496 412 476 297 338 385907 721 893 524 531 6561018 884 1043 663 728 794383 337 371 212 267 253653 62 695 455 479 49145 136 15 034 04 087508 44 478 294 377 304494 457 446 31 366 337286 283 259 194 203 188089 085 091 06 062 066095 098 094 065 07 065042 04 042 032 034 032271 257 245 19 211 189042 041 038 033 032 032

0707993 0708129 0712587 07124950512374 0512350 0512318 05123211900456 1911042 1885700 18877771571824 1582716 1575400 15789213912738 3950228 3921000 3931769


with OIB-like chemistry into the back-arc mantle with arc type com-ponents The wide range of NbLa and BaLa ratios (02ndash09 and10ndash40 respectively) of the Simav MHKS rocks suggest the interactionwith melts coming from both subduction-modified lithosphericmantle with arc-signature and asthenospheric mantle with OIB-likeintra-plate signature Ultrapotassic samples plot between the fieldsof E-MORB OIB and lithosphere in Fig 8a b and of intra-plate andarc-type in Fig 8c These results suggest that the transition from oro-genic (arc-type) to anorogenic (intra-plate)-type magmas betweenEarly to Late Miocene period could be interprated as gradually

increasing of presence of OIB-like intraplate magmas into the back-arc mantle with arc-type components

Radiogenic isotopic compositions of mafic potassic and ultrapotas-sic MHKS rocks (Table 2) range from 0707644 to 0708125 in 87Sr86Sr and from 0512372 to 0512398 in 143Nd144Nd Sample So7-8 is among the most primitive compositions (MgO 1013 wt Ni258 ppm) and has a 87Sr86Sr of 0708125 Innocenti et al (2005)reported a primitive sample with lamproitic affinity (MgO1069 wt Cr 719 ppm) from Simav-Uşak region which has a87Sr86Sr of 071028 Accordingly Aydoğan et al (2008) documented

Table 2 (continued)

KndashAr (Ma) High-K calc-alkaline series

205ndash207plusmn05 194plusmn05 197plusmn05

Daciterhyolite

Sample d-56 d-59 d-61 d-63 32 35 37 38 40 41 42 7UTM Coordinates e627434 e620165 e620827 e629430 e639656 e628200 e624152 e660850 e659750 e656125 e656158 e665450

n4337100 n4343210 n4342600 n4336333 n4335151 n4345810 n4346050 n4341210 n4344630 n4341250 n4344210 n435005SiO2 709 6536 6729 7643 7004 7542 7658 6766 6893 7172 7692 7161TiO2 036 053 052 007 036 007 006 035 04 024 007 023Al2O3 145 1544 1572 118 145 1285 1206 1433 14 1427 1156 1449Fe2O3 246 386 334 13 204 152 125 256 283 226 103 238MnO 002 005 004 002 005 004 001 005 006 005 001 002MgO 055 141 111 006 033 009 01 066 074 04 005 045CaO 176 348 293 014 143 043 041 178 192 1139 014 132Na2O 301 292 317 111 265 281 242 2 252 37 113 388K2O 486 386 407 816 643 506 459 514 522 46 812 49P2O5 013 0191 0163 0032 0156 0009 0026 0139 0149 0098 0016 009LOI 12 2 08 05 12 08 15 41 31 15 05 04Total 9975 9910 9915 9962 9918 9909 9900 9876 9986 9997 9954 9977Trace (ppm)Sr 2335 4026 3542 406 197 202 229 258 298 180 413 198Ba 948 1322 1079 232 868 94 52 969 1067 840 227 1452Rb 1958 120 1428 352 352 198 212 200 166 166 3434 154Ni 28 76 54 37 26 06 28 22 27 23 27 2Co 36 67 64 17 25 08 06 26 36 25 09 27Cr 14 41 55 48 75 82 55 205 34 32 43 27V 31 67 56 4 32 4 4 26 30 9 4 18Zr 1625 1767 179 919 163 131 86 190 192 1826 901 189Y 217 254 158 164 30 28 305 23 236 216 18 272Nb 144 138 136 125 153 192 203 142 138 146 119 19Ga 158 186 158 126 163 151 158 139 134 153 118 157Hf 43 49 51 34 48 57 45 56 59 49 37 59Pb 3 55 45 97 46 102 24 41 15 79 89 117Ta 15 12 12 1 14 16 17 14 13 13 1 18Th 229 187 20 298 23 321 356 325 303 211 274 253U 97 46 55 64 66 72 74 61 58 34 56 87

REE (ppm)La 433 454 416 335 411 337 203 428 429 404 336 538Ce 717 721 677 55 746 655 316 788 793 713 573 913Pr 884 931 848 736 832 878 628 913 91 811 721 1009Nd 289 303 267 225 279 311 222 316 35 26 241 335Sm 571 576 494 459 537 742 654 57 554 482 462 586Eu 093 111 101 043 091 019 015 078 086 07 039 096Gd 366 395 339 275 395 472 491 41 402 308 296 512Dy 356 445 325 295 442 486 511 448 434 372 3 455Er 219 267 172 189 288 285 29 236 237 209 177 253Tb 075 084 065 058 08 095 098 078 073 068 057 075Ho 078 091 061 062 096 098 108 079 082 076 06 09Tm 035 045 027 03 044 046 051 037 039 036 031 045Yb 212 25 168 173 278 282 299 239 233 223 195 257Lu 033 04 033 031 05 043 049 037 039 036 032 041IsotopeSr87Sr86 0709258 0709233 0709835 0709558Nd143Nd144 0512359 0512353 0512299 0512272Pb206Pb204 1893791 1890915 1890419 18524Pb207Pb204 1573569 1571326 1571977 15708Pb208Pb204 3912925 3905763 3908627 39045

(continued on next page)


Early Miocene (194 Ma) high-K calc-alkaline granitic intrusion withmantle-like isotopic signature (SiO2 6247ndash6827 wt 87Sr86Sr0704521ndash0705720) from adjacent Uşak province It appears that theprimitive nature of thesemafic rocks is not consistent with an explana-tion based on crustal contamination and must rather reflect large scalegeochemical heterogeneities in their mantle sources Incompatibletrace element fractionation and isotopic enrichments argue for thepresence of a clear crustal-derived signature in the Simav MHKS rocks

In contrast to the silica enrichment during assimilation ofcarbonate-free crustal rocks via uprising magma assimilation of

carbonate rocks leads to SiO2 depletion in potassic magmas and canexplain their silica-undersaturated variations (eg silica-poorleucite- and nepheline-bearing potassic magmas Dallai et al 2004Di Renzo et al 2007 Freda et al 2008 Iacono Marziano et al2008 Mollo et al 2010 Peccerillo et al 2010) However assimila-tion of both (carbonated and carbonate-free) crustal rock typesleads to incompatible trace element enrichments (eg Rb and La)but depletion in most compatible elements (eg Mg Cr Ni) andHREE and Y This is not the case in the potassic (shoshonitic absaro-kitic) and some of the ultrapotassic rocks (particularly Roman

Table 2 (continued)

206plusmn05

Granite Granite xenoliths Metamorphic

16 18a 19a 20 25a 29 18x 19x 25x MM1 MMKe681169 e682260 e683451 e679810 e682126 e664157 e682260 e683451 e682126 Simav region Salihli regionn4338171 n4345175 n4348790 n4348159 n4355795 n4343750 n4345175 n4348790 n43557957341 7095 7154 7294 7077 7156 6444 6446 6358 6361 7689028 037 03 03 034 024 064 064 056 0868 02531321 1393 1398 1353 1444 1451 1598 1623 166 1729 1253211 278 236 232 274 219 504 504 514 496 18004 006 005 005 005 005 011 011 011 0068 0014056 08 062 06 07 047 152 133 114 198 048158 211 177 142 205 15 331 352 35 29 043309 308 321 307 332 382 468 476 43 325 256489 486 506 5 477 461 171 194 365 257 4350094 0111 0087 009 009 008 018 02 011 019 00406 08 08 05 05 08 23 16 1 141 1319986 9985 9977 9982 9977 9983 9991 9983 9969 988 1007

150 233 215 172 222 173 215 232 228 242 51781 1157 865 949 1127 847 440 404 519 1139 281157 163 149 176 163 168 996 1106 160 101 19432 41 26 28 43 16 34 25 51 40 1028 41 27 32 41 2 62 48 61 9 248 615 48 82 27 75 41 78 48 50 2021 33 23 25 30 10 48 44 41 100 16164 155 142 155 165 169 237 2176 295 320 14024 20 206 23 194 22 354 44 52 396 346143 11 105 14 119 154 21 221 224 136 12145 142 135 142 154 154 192 181 205 22 1955 52 45 52 54 48 69 63 87 88 4337 34 38 33 35 8 89 59 52 7 1712 08 11 13 09 15 2 19 23 099 111821 186 228 253 375 197 30 14 478 268 14495 32 26 51 53 31 65 6 112 18 212

REE (ppm)393 534 629 415 528 355 29 109 152 588 289706 921 1092 754 941 639 55 233 373 123 585781 983 1165 84 1037 707 657 376 575 135 604273 341 393 249 333 236 262 195 261 52 214505 506 577 506 56 429 583 538 76 113 466071 098 08 073 095 068 079 071 098 206 0477306 294 347 335 308 295 554 66 71 967 397371 316 34 342 302 359 553 686 801 77 556223 178 181 214 182 215 331 429 525 397 376069 058 063 063 062 065 097 116 145 142 07908 063 065 078 066 07 117 144 176 143 124043 027 03 037 03 035 051 064 085 0559 0556239 175 179 244 183 226 323 407 494 35 333036 027 029 036 03 038 051 063 079 0535 0482

0709653 0709624 0709075 070988 07097 071655 0774180512354 0512398 0512379 051386 05123 051218 0512271891615 18840 18876 18942 18891 18604 19281157253 15685 15716 15721 15692 15703 1573391255 38952 39026 3907 38962 3967 39098


Province types) from Simav province On the MgO versus selectedLILEs and LREEs diagrams (Fig 5) these rocks show obvious positiverelationships between their MgO vs LILE (eg K2O Rb Th U andLREE) exactly opposite to the trends expected for crustal assimilationAlthough most of the ultrapotassic rocks (particularly lamproiticrocks) show consistent trends with crustal assimilation substantialcrustal contamination leads to higher 87Sr86Sr ratios which would beexpected to correlate negatively with MgO and with compatible ele-ments However their SrndashNdndashPb isotopic compositions do not correlatewith the geochemical parameters sensitive to crustal contamination

(see Fig 9abcd) Thus the absence of negative correlation of MgOand positive correlation of K2O with 87Sr86Sr (Fig 9a b) supports thelack of significant crustal contamination in the magmas CePb and RbLa versus 87Sr86Sr variations (Fig 9c d) also support this argument Incontrast as shown in Fig 10a b crustal contamination of the mantlesource is likely present in the MHKS rocks This is shown by the positivecorrelations between LaYb and La (Fig 10a) and the absence of any cor-relation between LaYb and 87Sr86Sr in MHKS rocks (Fig 10b) (cfCcediloban and Flower 2006 2007) This reinforces the idea that partialmelting played an important role in the distinct magma compositions

Fig 4 Classification diagrams for Simav magmatics a) Alkali (K2O+Na2O vs SiO2) diagram (Le Bas et al 1986) b) K2O vs Na2O diagram (Peccerillo and Taylor 1976) c) K2O vsSiO2 diagram (Peccerillo and Taylor 1976)


of mafic lavas whereas fractionation played a role within individualmagma series This also implies the possibility that the Simav potassicndashultrapotassic rocks were derived from various degrees of partial meltingof a heterogeneous source We propose that the post-collisional maficMHKS rocks from the Simav region could step from partial melting ofthe subduction-modified upper mantle hybridized by the involvementof subducted andor delaminated crustal components (discussedfurther)

In summary our results imply that a subduction-modified (viaslab-released fluidsmelts) mantle source that was enriched withcrustal (eg marls metapelites) components (prior to partial melt-ing) and mixed with asthenospheric mantle in a back-arc mantlewedge could be responsible for the generation of Simav Early-Middle Miocene alkaline MHKS rocks

6111 The nature of crustal inputs and pathways in the origin of MHKSrocks It is generally accepted (eg Beccaluva et al 1991 Johnson andPlank 1999 Peccerillo andMartinotti 2006 Prelevic et al 2008) thatthe enrichment processes in the mantle sources of potassic magmasoccur mostly during subduction either as a result of the incorporationof pelagic sediments fluidsmelts from the dewatering of oceaniccrust or continental crust-derived components (eg dragged terrige-nous sediments eroded upper crustal rocks delaminated lower crust-al rocks) with low and constant NbU ratios (~5ndash10 Barth et al 2000Hofmann et al 1986 Plank and Langmuir 1998 Sims and De Paolo1997) Thus the low NbU ratios (4ndash11) of the Simav mafic seriesrocks indicate a significant pelagic sediment andor crustal contribu-tion into their mantle source (Fig 11a) Ba Cs and Pb elements aremobile in aqueous fluids (eg Hooper and Hawkesworth 1993) andthus variation of BaLa (10ndash20) PbLa (0015ndash1) and CsRb(001ndash01) ratios in Simav rocks may be used as indicators of therole of aqueous fluid metasomatism in their genesis On the basis oflight stable (boron and lithium) isotopic data the contribution ofslab-derived aqueous fluids from the dewatering of oceanic crust on

the genesis of Early-Middle Miocene calc-alkaline and potassicmagmas from Western Anatolia has been proposed by some authors(eg Agostini et al 2007 2008 2009 Innocenti et al 2005Tonarini et al 2005) High Sr isotope and high CeSr and ThTa ratiosfor Simav MHKS rocks (Fig 11b) may also suggest that the variousamounts of fluidsmelts released by melting of different types of sub-ducted crustal rocks (eg metapelite carbonate) contributed to theirmantle source (eg Boari et al 2009a 2009b Conticelli et al 20072009a 2009b 2010 Nikogosian and van Bergen 2010 Tommasiniet al 2011) This signify that the nature of the diverse crustal materials(eg metapelites and marls) added into their mantle source domains(eg Avanzinelli et al 2009 Boari et al 2009a 2009b Conticelli et al2009a 2009b 2010 Thomsen and Schmidt 2008) played a significantrole in the compositional variations of Simav mafic potassic rocks (egshoshonitic Roman Province Type lamproitic and absarokitic) Asshown in Figs 6 8 11 geochemical consistency with the pattern of in-compatible elements for upper crust and average crust and isotopicsimilarity with the lower crustal metasediments support an originfrom the overriding plate for crustal contaminants

Moderately high ThLa (018ndash036) and ThNb (035ndash113) ratios ofSimav potassicMHKS rocks also require additional (crust-derived) com-ponent on their genesis as is typical of potassic magma sources (egConticelli et al 2009a 2009b Peccerillo 2005 Peccerillo andMartinotti 2006 Plank 2005) The crustal inputs for Simav MHKSmagmas were likely derived from subducted sediments and draggedandor delaminated crustal rocks in the Aegean trench The PbRb PbK2O and SmHf ratios for the Simavmagmatic rocks can be useful guidesto refine the nature of the subducted (pelagic or crust-derived terrige-nous) sedimentary components Compared to pelagic sediments (PbRb 030ndash037 and PbK2O 12ndash14 Shimoda et al 2003 SmHf average3 Handley et al 2011 Vervoort et al 1999) terrigenous sedimentshave lower PbRb (015ndash02) PbK2O (0ndash8) and SmHf (average 1) ra-tios In the case of the Simavmaficmagmatic rocks potassic andultrapo-tassic (MHKS) rocks are characterized by low PbRb (up to 02) PbK2O

Fig 5 Harker variation diagrams for selected major (wt) and trace (ppm) elements vs MgO (wt) for Simav rocks Data for Kula basalts after Alıcı et al (2002) Other data forSimav magmatics from the literature (see in the text) are also plotted For symbols see Fig 4


(0ndash8) and SmHf (05ndash15) ratios These values for the Simav potassicMHKS rocks suggest a major role for crustally-derived terrigenous sedi-mentary sources rather than pelagic sediments in the origin of absaroki-ticshoshonitic-ultrapotassic magmas However Simav potassic MHKS

rocks with lower PbRb PbK2O and SmHf ratios are also analogous tohigh-K calc-alkaline series rocks of lower crustal derivation (eg PbRb 001ndash015 PbK2O 0ndash10 SmHf 08ndash15) They possess strong isoto-pic similarity to terrigenous sediments of the Aegean Sea (Nile river

Fig 6 REE patterns normalized to chondrites (Sun and McDonough 1989) and incompatible element patterns normalized to primordial mantle (Wood et al 1979 except Pb fromSun and McDonough 1989) of Simav mafic potassic series rocks (andashb) and high-K calc-alkaline series rocks (cndashd) (e) normalized incompatible element patterns of xenoliths (ingranite) and metamorphic basement rocks GLOSS Global Subducting Sediments (Plank and Langmuir 1998) Upper crust from Taylor and McLennan (1985)


87Sr86Sr 0707043 143Nd144Nd 0512469 206Pb204Pb 1863ndash1901207Pb204Pb 15628ndash15687 208Pb204Pb 38374ndash39000 Pe-Piper1994 Weldeab et al 2002) as well as high-K calc-alkaline seriesrocks Accordingly the radiogenic Pb component of the Simav samplesthat overlap in the fields of Rhodopean metamorphic basement anddredge sediments is likely to be derived from radiogenic componentfrom subducted continental material equivalent to terrigenous sedi-ments from the Nile-river (Fig 11c) This implies that crustal contribu-tions could have come from subducted terrigenous sediments as wellas direct addition of dragged andor delaminated (lower andor upper)crustal rocks into the mantle source domain of the Simav MHKS rocks(cf Ccediloban and Flower 2007 Lustrino et al 2007 Peccerillo andMartinotti 2006) Direct addition of crustal material could have takenplace via crustal delamination andor erosion processes resulting fromcontinental subduction (discussed further below)

6112 Source mineralogy and source location of the mafic series In theSimav mafic series rocks the positive trends of MgO vs Ni and Cr(Fig 5) clearly indicate fractional crystallization of olivine and clino-pyroxene as a first order evolutionary process The highest contentsof La Ce Nd and P2O5 of ultrapotassic rock samples (particularly lam-proites) which are the most primitive rocks in the MHKS series (egInnocenti et al 2005) suggest the presence of apatite in theirenriched mantle source because apatite is the main carrier of LREEin the mantle (eg OReilly and Griffin 2000) As mentioned beforeand shown in Fig 5 potassic (absarokitic-shoshonitic) basalts displayconsiderably lower concentrations for most incompatible trace ele-ments for similar MgO contents with respect to ultrapotassic sam-ples with near primitive natures Major element (eg CaO TiO2P2O5) LILE (eg Rb LREE) and HFSE (eg Hf Zr Nb) values increasewith increasing K2O Cr and Ni contents from potassic to high-K

Fig 7 ThZr vs NbZr (a) and ThndashHfndashNb2 (b) discrimination diagrams between orogenic and anorogenic magmas for Simav magmatics (Krmiacuteček et al 2011 Wilson and Bianchini1999) Plio-Quaternary basalts from Alıcı et al (2002) and Late Miocene basalts from Innocenti et al (2005) Ersoy et al (2008) and Agostini et al (2007) For symbols see Fig 4


alkaline rocks These variations reflect a heterogeneous upper mantlevariably enriched in LILE and HFSE

As for the metasomatic event affecting source mantle rocks thesimilar isotopic compositions of the potassic and ultrapotassicMHKS rocks support a similar metasomatic agent and nature of meta-somatism The observed difference in LILELILE ratios betweenshoshonitic and ultrapotassic rocks may depend on the source miner-alogy (eg occurrence of different proportions of phlogopite and am-phibole) (cf Frezzotti et al 2007) andor the degree of partialmelting

The potassic nature of the enriched mantle sources of potassic andultrapotassic rocks is chiefly controlled by phlogopite andor amphi-bole (eg richterite) The whole rock RbSr and BaRb ratios can be in-dicative of a phlogopite- andor amphibole-bearing mantle source(ie Ionov et al 1997) The partition coefficients for phlogopite are D-RbgtDBa Thus the high RbSr (015ndash07) and low BaRb (b10) ratios ofSimav high-K mafic lavas are compatible with partial melting ofphlogopite- (plusmn amphibole) bearing mantle sources relative toamphibole- (plusmn phlogopite) bearing mantle source for theshoshonitic-absarokitic basalts with low RbSr (01ndash02) and highBaRb (up to 20) ratios Samples from the MHKS series have elevated(TbYb)N (see Fig 12a) indicating garnet-bearing mantle sources forthe potassic and ultrapotassic samples The trend on the meltingcurve (Fig 12b c) of a metasomatized phlogopite-amphibole-bearing garnet lherzolitic mantle source for ultrapotassics and potas-sic rocks (on LaSm versus SmYb and GdYb versus LaYb diagrams)probably suggests that different proportions of phlogopite and am-phibole played a significant role in the source nature of mafic potassicrocks Thus it is suggested that the difference between shoshoniticrocks and ultrapotassic rocks could be explained by variable degreesof partial melting of a modally variable phlogopite and amphibole-bearing heterogenous mantle source

The consensus view is that potassic and ultrapotassic rocks are de-rived by partial melting of metasomatically veined-lherzolitic or harz-burgitic lithosphere (eg Foley 1992) A plausible scenario forpotassic-ultrapotassic melt generation could invoke i) melting ofphlogopite- plusmnamphibole- clinopyroxene- and apatite-bearingveins in garnet lherzolite at the uppermost mantle producing ultrapo-tassic magma batches and ii) melting of amphibole- plusmnphlogopite-clinopyroxene- and apatite-bearing veins in garnet lherzolite at theuppermost mantle producing potassic magma batches Howeversilica-poor ultrapotassic rocks also require the presence of carbonatein their mantle domains unless carbonate assimilation has occurredduring magma ascent The location of mantle source region dealswith the thermal stability of the required source mineralogy such as

phlogopite Since phlogopite is stabile under PndashT conditions of thecold mantle lithosphere relative to the temperatures of convectingupper mantle Tappe et al (2006) emphasized that this restricts gen-eration of phlogopite-bearing mantle-derived magmas to lithosphericmantle and does not reject a contribution from the convecting as-thenospheric upper mantle As shown in Fig 12d the most primitive(mantle-equilibrated) Simav MHKS rocks have MgOCaO ratios be-tween 07 and 16 (Fig 12d) which are much lower than in experi-mentally produced carbonated garnet lherzolite (Gudfinnsson andPresnall 2005) suggesting shallow level magma segregation depthlow-pressure fractionation and upper (lithospheric) mantleconditions

612 High-K calc-alkaline seriesRadiogenic Sr and Nd isotopic compositions of the Simav high-K

calc-alkaline magmatic rocks define restricted ranges (Table 2)87Sr86Sr and 143Nd144Nd isotopic compositions of high-K calc-alkaline intermediate-silicic (andesitic-daciticrhyolitic) rocks andgranite xenoliths range from 0707993ndash070988 for 87Sr86Sr and0512339ndash0512383 for 143Nd144Nd except for two rhyolite sampleswith higher 87Sr86Sr (0712495 and 0712587) and lower 143Nd144Nd (0512318 and 0512321) ratios Pb isotopic ratios of the silicicseries rocks and granite xenoliths (206Pb204Pb 1852ndash1911042207Pb204Pb 15685ndash1582716 208Pb204Pb 38952ndash3950228) arenot far from the Pb isotopic compositions of two analyzed metamor-phic samples (206Pb204Pb 18604ndash19281 207Pb204Pb15703ndash15730 208Pb204Pb 39098ndash39670) Increasing Sr and de-creasing Nd isotopic values of the rhyolitic samples towards valuestypical of the Menderes metamorphic basements(0716542ndash0774177 for 87Sr86Sr and 0512184ndash0512273 for143Nd144Nd) suggest possible upper crustal contamination of themagmas In terms of the MgO and K2O vs 87Sr86Sr (Fig 9a b) dia-grams the fact that only the less mafic rocks become more radiogenicin 87Sr86Sr suggests the importance of crustal assimilation in the or-igin of the more evolved silicic samples Similarly as shown inFig 11c the increase in 207Pb204Pb ratios of silicic (daciterhyolite)high-K calc-alkaline samples could be attributed to the increasing im-portance of upper crustal contamination of rising magma Isotopicoverlap in these diagrams between mafic and intermediate-silicic se-ries rocks also suggests that significant contributions from mantle-derived melts exist in the genesis of high-K calc-alkaline rocks Coge-netic dacites-rhyolites possibly derived from intermediate (andesitic)magmas by evolutionary processes such as crustal fractionationmatched by extent of crustal assimilation As mentioned before theorigin of Early Miocene (194 Ma) high-K calc-alkaline granitic

Fig 8 a) BaLa vs NbLa b) NbLa vs LaYb and c) BaLa vs LaTa variation diagrams ofthe Simav mafic serie rocks Data source E-MORB and NMORB (Sun and McDonough1989) Lithosphere (Gill 1981) Average OIB average lower crust and the black linesseparating fields of the asthenospheric lithospheric and mixed mantle are takenfrom Abdel-Fattah and Philip (2004) and Abdel-Rahman (2002) (references therein)Intra-plate and arc area in Fig 8c is from Kay and Copeland (2006)


intrusions with mantle-like isotopic signatures (SiO26247ndash6827 wt 87Sr86Sr 0704521ndash0705720) from neighboringUşak province is attributed to the mixing of lithospheric mantle-derived magmas with lower crustal-derived magmas (Aydoğan etal 2008) We suggest that the mixing of mantle-derived maficmagmas with silicic melts from the lower crust resulted in calc-alkaline magmas generated at mantle conditions which underwentcrustal contamination only in the more evolved silicic magmas

Thus we propose that underplating of Simav mafic magma and mix-ing with lower crust-derived magmas matched by some extent of as-similation of crust during partial melting appears as the likelymechanisms for the generation of the Simav calc-alkaline magmasproducing volcanic (Karaboldere andesite dacite and rhyolites) andplutonic (Eğrigoumlz and Koyunoba granite-granodiorite) end-members

7 Isotopic evidence for source contamination in the origin of theSimav magmatic series

The Simav MHKS and high-K calc-alkaline rocks exhibit the typicalgeochemical characteristics of subduction-related magmas [high LILEPb concentrations relative depletion in Nb and high 87Sr86Sr and207Pb204Pb and low 143Nd144Nd (Figs 13 14a b) Trace elementREE and isotopic data for the Simav magmatic rocks also reveal strik-ing similarities betweenmafic potassic and high-K calc-alkaline seriesrocks that overlap in age (Early to Middle Miocene period) and wereemplaced in the same tectonic setting Isotopic compositions of theSimav mafic and intermediate-silicic igneous rocks pointing out acommon mantle source are comparable to those of other rift-related igneous rocks throughout the Mediterranean region(Fig 13) SrndashNdndashPb isotope ratios depend on both the type of mantlesource and the amount of incorporated crustal component Isotopiccomposition patterns for 87Sr86Sr 143Nd144Nd and 206Pb204Pb ofthe Simav potassic mafic rocks are distinct from those of the OIB-like Kula basalts and ancient subcontinental lithospheric mantle(Figs 14ab 15) The Simav magmas overlap with EM-II signaturesand can be explained as incorporating isotopically distinct end mem-ber components which mixed in variable proportions prior to melt-ing andor crustally contaminatedassimilated during magmaevolution In 87Sr86Srndash206Pb204Pb space and in 143Nd144Ndndash206Pb204Pbndash143Nd144Nd space (Fig 14ab) most of the data from individu-al magma series define distinct linear Sr and Pb isotopic arrays indi-cating that there exists a significant heterogeneity in the componentspresent within each of the trends These are best seen on 206Pb204 Pbversus 207Pb204Pb and 206Pb204Pb versus 208Pb204 Pb diagrams(Fig 15a b) suggesting the role of three distinct (crustal subconti-nental lithospheric mantle and asthenospheric mantle) sources inthe genesis of Simav magmatic rocks

In 206Pb204Pbndash87Sr86Srndash143Nd144Nd space the Simav samplesdefine a curvilinear trend (Fig 14) This trend is identical to thoseshown by other potassic volcanic suites from the Central and North-East Anatolia (Alpaslan et al 2006 Altherr et al 2008 Eyuumlboğlu2010) and can be interpreted as mixing between mantle and crustalend-members The mantle end-members are characterized by (i)high 87Sr86Sr and relatively low 143Nd144Nd and 206Pb204Pb values(subcontinental lithospheric mantle source Brandon and Goles1995) and low 87Sr86Sr and 206Pb204Pb and high 143Nd144Ndvalues (asthenospheric mantle source Kula basalts Alıcı et al2002) The crustal end-member could be lower or upper crust or sub-ducted sediment or assimilated of upper crustal material as well (cfHarangi et al 2007) The potassic-ultrapotassic rocks of the Simav re-gion range from compositions near bulk solid Earth estimates (87Sr86Sr~0705143Nd144Nd~05127) to crustal-like enriched composi-tions As shown in Figs 11c 14 15 Simav high-K calc-alkaline andmafic magmatic MHKS samples completely overlap the lead isotopiccomposition of the metamorphics (Rohodopean-Bulgaria Pannonianbasin) Nile river and dredge sediments but the compositions of themafic rocks with high MgO Ni and Cr contents close to the valuesofmantle-equilibratedmelts Therefore we suggest that the observed207ndash208 Pb isotope data arrays for Simav MHKS rocks may reflect thesubducted (lower andor upper) crustal materials (cf Elburg et al2004) as well as terrigenous sediments entrained into the mantleas a result of continental subduction (see below) Large-scale hetero-geneity of the Simav magmatics revealed by the Pb isotope data isalso consistent with the EM-II array between lower crust and

Fig 9 Variation diagrams of 87Sr86Sr vs MgO (a) K2O (b) CePb (c) and RbLa (d) for Simav magmatics ACC Average continental crust (Rudnick and Gao 2004) For symbols seeFig 4 Marlstone is taken from Conticelli et al (2009a)


asthenosphere (Fig 14a b) These isotopic results are in agreementwith an important role for crustal source contamination rather thancrustal contamination of ascending magmas in the genesis of SimavEarly-Middle Miocene mafic MHKS rocks We do not ultimately ruleout the importance of crustal assimilation processes even smallamounts of crustal assimilation may significantly shift radiogenic iso-topes during magma evolution However continental crust assimila-tion is unable to explain geochemical trends and high Sr and Pbisotopic values observed in the mafic MHKS samples with near-primitive nature In contrast the assimilation of upper crustal materi-al in the genesis of silicic calc-alkaline rocks can be considered on thebasis of SrndashNdndashPb isotope data for these rocks which support theirinvolvement in the petrogenesis of the more evolved high-K calc-alkaline magmas

For Simav MHKS rocks we consider a metasomatized EM-II typemantle source modified by slab-derived and crustal material-derived fluidsmelts The mafic melt formed from this metasomatizedmantle source variably contaminated with the terrigenous sedimentsand (lower andor upper) crustal components (eg marl metapelite)and mixed with influxed asthenosphere in back-arc mantle wedgeAccordingly the isotopic variation of high-K calk-alkaline magmascan be explained the mixing of mafic melts derived from EM-II typemetasomatized mantle with silicic melt from the lower crust withthe extent of upper crustal contamination

Chemical and isotopic evidence demonstrating close similaritiesbetween Simav mafic potassic and high-K calk-alkaline rocks mustnow be placed in the context of the geodynamic evolution of the re-gion (see Section 9)

8 Regional tectonic significance of Simav orogenic magmas

In contrast to the scarcity of Plio-Quaternary Turkic-type anoro-genic potassic magmas (eg lamproites shoshonites) (eg Denizliand Isparta regions Ccediloban and Flower 2007 Ccediloban et al in prepSemiz et al in press Yılmaz 2010) Early to Middle Miocene orogenicpotassic (shoshonites) and ultrapotassic (lamproites RomanProvince-like) magmas affected Western and Southwestern Anatoliaand Aegean at several regions eg Ccedilanakkale Kuumltahya Uşak Afyonregions in the north (eg Aldanmaz et al 2000 Ccediloban and Flower2007 Innocenti et al 2005) İzmir (Foccedila Karaburun) and Balıkesir(Ayvalık) regions in the west (eg Agostini et al 2010 Akay andErdoğan 2004) and Bodrum and Kos regions in the southwest (egPe-Piper and Piper 2007)

Current studies reveal that the OligocenendashMiocene period inWestern Anatolia included rapid regional uplift (eg extensionaluplifting of Kazdağ and Uludağ massif at north and Menderes Massifat south) and extensional tectonism (Bozkurt et al 2011 Cavazzaet al 2009 Okay et al 2008) Chronological dating of Simav magma-tism clearly indicates that Simav mafic potassic (Payamtepe and Naşavolcanics) and high-K calc-alkaline (Eğrigoumlz and Koyunoba granitesand Karaboldere andesite daciterhyolites) rocks coevally developedunder an extensional stress regime (eg extensional exhumation ofgranites) Post-collisional (extension-related) magmatism in Simavregion demonstrates two discernible magmatic patterns in spaceand time 1) Late OligocenendashMiddle Miocene magmas with orogenicgeochemical signatures and 2) Late-MiocenendashPlio-Quaternarymagmas with transitional and anorogenic geochemical signatures A

Fig 10 Variations in (a) LaYb vs La and (b) LaYb vs 87Sr86Sr in Simav mafic serieslavas For symbols see Fig 4

Fig 11 Logarithmic plots of variations in NbU vs Nb (a) CeSr vs ThTa (b) and 208Pb204Pb vs 207Pb204Pb (modified from Elburg et al 2004) (c) in the Simav igneous rocksData for the Late Miocene basalts (Innocenti et al 2005) Kula basalts (Alıcı et al2002) MORB and OIB (Hofmann et al 1986) continental crust and pelagic sediments(Sims and De Paolo 1997) in Fig 11a are plotted for comparison Metasediments andMarls in Fig 11b are from Peccerillo (2005) OIB MORB and dredge sediments inFig 11c are from Elburg et al (2004 references therein) and marlstone is taken fromConticelli et al (2009a) Metamorphic basement from Rhodopean is from Marchev et al(2004 references therein) Nile river sediments in the same figure are from Pe-Piper(1994) and Weldeab et al (2002) For symbols see Fig 4


gradual transitional period fromorogenic-type to anorogenic-type potas-sic magmas probably corresponds to inception of extensional basin for-mations following the uplifting of Menderes Massif In the Simav andsurrounding regions no shoshonitic and ultrapotassic magma are ob-served prior to late Oligocene Simav potassic (shoshonitic-absarokitic)and ultrapotassic (MHKS) magmas (Naşa and Payamtepe volcanics)only appear (just or) after late Oligocene extensional uplift of the meta-morphic basements (eg the Menderes Massif) This magmatism maycorrespond to last stage of regional uplifting and an onset of Early-Middle Miocene extensional regime (formation of extensional basins)The sudden appearance of Early-Middle Miocene MHKS-type maficmagmas (eg shoshonitic lamproitic RPT-type) suggests a strikingchange of mantle source Similar uplifting and related extensionalbasin formationwere also observed during Late-MiocenendashEarly Plioceneperiod in the south of Simav (Bozcu 2010) corresponding to timing ofinitiation of Late Miocene potassic magmas (eg Denizli lamprophyresSemiz et al in press Kabaklar basalt Agostini et al 2007) These obser-vations reveal that the sudden spurt of Western Anatolian post-collisional potassic magmas is a tectonomagmatic tracer for the timingof last stage of regional uplifting and onset of extensional basin forma-tions in different periods

9 Geodynamic synthesis

NeogenendashQuaternary magmatism in Western Anatolia is closelyassociated with the assembly of microterranes during the late stagesof Tethyan closure and has been variously linked to the processes ofsubduction microcontinental collision and asthenospheric upwelling(eg Aldanmaz et al 2000 Şengoumlr and Yilmaz 1981) The AnatolidendashTauride continental block (ATB) rifting away from Gondwana (Afri-ca) underwent Paleocene or Eocene collision with the Sakaryamicro continental block (Eurasia) (Şengoumlr and Yilmaz 1981 van

Hinsbergen et al 2010a) after which AfricandashEurope convergencewas accommodated to the south and western Turkey underwent ex-humation and eventually Miocene extension

Fig 12 For Simav mafic series rocks a) variations of BaRb vs RbSr b) plot of TbYb and LaSm normalized to primitive mantle values (Sun and McDonough 1989 division be-tween spinel and garnet dominated melting is from Wang et al (2002 references therein) OIB from Sun and McDonough (1989) c) LaSm vs SmYb and d) GdYb vs LaYb di-agrams Am amphibole Phl phlogopite Gt garnet lherz lherzolite d) Simav MHKS rocks in the MgOCaO vs SiO2Al2O3 (Tappe et al 2006) Melting curves are adapted fromFengmei et al (2006 references therein) and Zhang et al (2008 references therein) Sp spinel Phl phlogopite Shaded fields of experimentally determined garnet lherzolitemelt compositions after Gudfinnsson and Presnall (2005)

Fig 13 Plots of 143Nd144Nd vs 87Sr86Sr for Simav magmatics and Menderes metamor-phics Orogenic and anorogenic fields are adapted from Bianchini et al (2008) andWilson and Bianchini (1999) references therein For comparison Kula basalts (Alıcıet al 2002) Camardı-Niğde (Central Anatolia) ultrapotassics (Alpaslan et al 2006)Everekhanları-Bayburt (NE Anatolia) ultrapotassics (Altherr et al 2008 Eyuumlboğlu2010) Late Miocene basalts (Agostini et al 2007 Innocenti et al 2005) are also plot-ted Symbols as in Fig 4


For most of the Cenozoic the Aegean has been the back arc regionof a convergent plate margin driven by subduction of African litho-sphere (eg Edwards and Grasemann 2009) Recent seismologicaland tomographical studies indicate that the Aegean basin openedslowly behind a shallow dipping slab (Agostini et al 2010Carminati and Doglioni 2004 Doglioni et al 2007 Faccenna et al2003 Sodoudi et al 2006) Royden and Papanikolaou (2011) indicat-ed a slab segmentation and late Cenozoic disruption of the Hellenicarc and Gesret et al (2011) suggested flatter subduction of a differentslab segment of Hellenic subduction zone The subducting slab be-neath the Aegean region consists of alternating segments of oceaniclithosphere and continental lower crust and lithospheric mantle(Faccenna et al 2003) According to van Hinsbergen et al (2010a)nappe systems (eg the Lycian nappes and carbonate platforms)and metamorphic basement (eg the Menderes Massif) belong tothe Anatolide-Tauride Block and represent crust accreted at thetrench overriding the Eurasian plate They suggested that subductingAfrican mantle lithosphere delaminated from accreting crust (be-tween 45ndash20 Ma) During delamination asthenospheric mantleflows probably contributed to the inception of the uplifting and ex-tensional stages and the heating of the overriding plate The upliftof the Menderes Massif could be interpreted as a result of shallowsubduction of African oceanic lithosphere beneath Western Anatolia(Prelevic et al 2010) or of roll-back of the Aegean slab since slabrollback-induced upward flows contributes to uplift (eg Faccennaet al 2010 Husson et al 2009) or of global scale mantle flows(Agostini et al 2009 Ccediloban 2007 Flower et al 2007 Kovaacutecs et al2012)

Fig 14 87Sr86Sr and 143Nd144Nd vs 206Pb204Pb variation diagrams for Simav rocksMORB EM II are from Zindler and Hart 1986 Lower crust is from Harangi et al(2007) Others are same with Fig 4 For comparison Kula basalts (Alıcı et al 2002)and Upper CretaceousndashTertiary ultrapotassics from Central and NE Anatolia (Alpaslanet al 2006 Altherr et al 2008) are also plotted FOZO adapted from Stracke et al(2005) Ancient SCLM adapted from Brandon and Goles (1995) For symbols see Fig 4

Fig 15 206Pb204Pb versus 208Pb204Pb and 207Pb204Pb for the Simav magmatic rocksand Menderes metamorphic basement Kula basalts after Alıcı et al (2002) Data forthe metamorphic basement from Rhodopean is from Marchev et al 2004 EM II andHIMU are from Zindler and Hart (1986) Marlstone is from Conticelli et al (2009a2009b) FOZO adapted from Stracke et al (2005) Ancient SCLM adapted from Brandonand Goles (1995) For symbols see Fig 4


Neogene magmatic activities in Western Anatolia are associatedwith the progressive development of extensional basins (fromNorth to South) and get younger from North to South (Bingoumll et al1982 Fytikas et al 1976 Fytikas et al 1984 Pe-piper and Piper2001) Accordingly with a time shift from North to South the samegeodynamic setting of the AegeanndashWestern Anatolian region pro-gressed from north to south (Agostini et al 2009) The OligocenendashMiddle Miocene extensional basins and associated magmatism inWestern Anatolia could be interpreted to be related to trench retreatalong the northern Hellenic trench whereas the Late MiocenendashPlio-Quaternary extensional basins and related magmatism could be relat-ed to progressive rollback mechanism of the subducted slab in thenorthern Hellenic trench (eg Burchfiel et al 2008 Dumurdzanovet al 2005 Papanikolau 2010 Royden and Papanikolaou 2011Yılmaz 2010) Ccediloban (2007) proposed that the Aegean extensionmay be driven by hot asthenospheric mantle flow which displacedlaterally prior to and during the ArabiandashEurasian collision providinga thermal source for concomitant (postcollisional) intra-plate mag-matism We proposed that the dynamic interplay of both early- (Oli-gocenendashMiddle Miocene trench retreat shallow subduction uplifting

and extension) and late-stage (Late MiocenendashPlio-Quaternary slab re-treat uplifting and extension) processes and related magmatism inWestern Anatolia was mainly driven by global scale asthenosphericmantle flows associated with plate dynamics Recent Pn tomographicresults in Western Anatolia are consistent with this interpretation(eg Mutlu and Karabulut 2011) In other words Endrun et al(2011) proposed that the deformation of the northern Aegean Sealithosphere is coherent in the sense that from the upper crust downto the lithospheric mantle it undergoes the same region-scaleNorthndashsouth extension High-resolution images of mantle-wedgestructures along the western Hellenic subduction zone (Pearce et al2009) also reveal the existence of an ~20 km thick low-velocitylayer which is interpreted as shallowly subducted continental crustbeneath northern Greece (dipping~19deg) Papanikolau (2010) andRoyden and Papanikolaou (2011) suggested that the differentiation(and disruption) of the Hellenic arc occurred in Late Miocene separat-ing a northern segment where continental subduction continuedfrom a southern segment where oceanic subduction started The tran-sition from slow continental subduction in the Late Miocene to rapidoceanic subduction in the Plio-Quaternary in the southern Hellenideswas driven by a roll-back mechanism The development of the pre-sent Hellenic arc and trench system is the result of oceanic subduc-tion of the East Mediterranean Basin Such a geodynamic scenario ifconfirmed shows that significant amounts of shallowly subductedcontinental crust exist beneath the Anatolian lithosphere This crustwas incorporated into the mantle-wedge between the African slab

Fig 16 Schematic sketch depicting possible formation model of Simav coeval generated Early-Middle Miocene mafic potassic and high-K calc-alkaline magmatic rocks (remodifiedfrom van Hinsbergen et al 2010a) CAG high-K calc-alkaline granite CAV high-K calc-alkaline volcanics MHKS Medium-high K absarokite shoshonite and ultrapotassic maficserie EM-II EM-II type metasomatized mantle SB Sakarya Block ATB Anatolide-Tauride Block İzmir-Ankara Suture Zone


and the overriding Anatolian lithosphere This geodynamic scenario isconducive to the generation of a large variety of magmaticassociations

As outlined in Section 61 geochemical and isotopic characteristicsof the Simav MHKS rocks suggest a mixture of diverse source compo-nents Subducted crustal materials (terrigenous sediments erodedupper or lower crustal rocks) or delaminated lower crustal rocks arepossible candidate sources of continental materials added to the man-tle source of the Simav MHKS magmas During this episode coevalhigh-K calc-alkaline (plutonic and volcanic) magmas were derivedfrom mixing of silicic melts from lower crust with mantle-derivedmagmas Zhu et al (2006) stated that the Menderes Massif is under-lain by a crust with a thickness of 28ndash30 km This suggests that themetabasaltic-eclogitic (eg Okay et al 2002) bottom of the over-thickened crust may become denser than the underlying mantleand undergo delamination (gravitational instability) (eg Anderson2005) During this period a gravitational tectonic collapse can alsobe expected under extension (eg Buck and Sokoutis 1994Meissner and Money 1998 Willbold and Stracke 2010) Delamina-tion of lower continental crust also requires concomitant delamina-tion of subcontinental lithospheric mantle (eg Kay and Kay 1993Schott and Schmeling 1998 Willbold and Stracke 2010) Replace-ment with warmer asthenospheric mantle flows induces significantuplift at the surface that can proceed or be coeval with the initiationof extension (eg Marotta et al 1999) Combined with the existenceof substantial geochemical and isotopic (SrndashNdndashPb) overlap betweenlower crust-derived high-K calc-alkaline rocks and mafic potassic se-ries we propose that delamination of subducted accreted crust (asconcomitant with the lithospheric delamination) is themost likely ex-planation for the generation of potassic mafic magmas in the Simavregion

As shown in Fig 16 subduction of accreted ATB (Anatolide-TaurideBlock) crust at shallow levels beneath Anatolian lithosphere develop-ment of thickened crust and delamination of subducted crustal rockstogether with concomitant delamination of subcontinental lithosphericmantle influences of slab-derived and crustal materials-derived fluidsmelts and mix with added asthenosphere can explain the newlyformed metasomatized (EM-II type) mantle source and the origin ofthe Simav mafic potassic magmas During this episode global scale as-thenospheric mantle flows (cf Agostini et al 2009 Ccediloban 2007Flower et al 2007 Kovaacutecs et al 2012) in the mantle wedge and hotupwelling asthenospheric mantle triggered partial melting not onlyat upper mantle levels but also in deeply rooted continental

lithosphere Asthenosphere penetrated into the wedge that (gradually)opens up between the exhuming crust and the slab (Fig 16) thus heat-ing the thick crust leading to additional partial melting Variable de-grees of partial melting of the lower crust (via underplating of maficmagmas) and mixing with potassicndashultrapotassic magmas may haveresulted in coeval generation of Early-Middle Miocene calc-alkalinemagmas in Simav region

10 Conclusions

The Simav region of Western Anatolia is within a post-orogenic(back-arc) area associated with the South AegeanndashHellenic subduc-tion system and is characterized by extensional basins hosting vari-ous types of Early to Middle Miocene magmatic rocks One of theintriguing features of the Simav region is the coexistence during theEarly to Middle Miocene of mafic and intermediate-silicic magmasof very similar geochemical and isotopic characteristics in the exten-sional geodynamic setting Trace element and Pb Nd and Sr isotopicdata provide clues for understanding the origin of these magmas andtheir geodynamic relationships The major results are outlined below

i) The Simav (Early to Middle Miocene) magmatic complex in theWestern Anatolia extensional province comprises mafic andintermediate-silicic series rocks The mafic series rocks includethe Payamtepe and Naşa mafic potassic (medium-K shosho-nite absarokite and high-K ultrapotassic MHKS) volcanicswhereas the Eğrigoumlz and Koyunoba granites and Karaboldereintermediate-silicic volcanics (andesite trachyandesite daciteand rhyolite) represent the high-K calc-alkaline series rocks

ii) Radiometric dating of the Simav magmatic rocks show thatmafic potassic-ultrapotassic (205ndash153 Ma) and high-K calc-alkaline (228ndash125 Ma) magmas coexisted in the same tecton-ic setting during the Early-Middle Miocene Another key obser-vation is that both potassic mafic and high-K calc-alkalineseries rocks have typical orogenic (arc-type) geochemical sig-natures with distinctive major and trace element characteris-tics (variably enriched LILE low abundances of HFSE and highLILEHFSE ratios) and similar isotopic ratios

iii) Trace element variations argue for a role for different propor-tions of phlogopite and amphibole in veins in the garnet lher-zolitic mantle sources of the Simav mafic series rocks SimavEarly-Middle Miocene mafic potassic rocks with low PbRb(up to 02) and SmHf (05ndash15) ratios also suggest a


metasomatic agent that included crust-derived components intheir origin

iv) The high 207Pbndash208Pb isotope signatures of Simav MHKS rocksreflect the input of subducted or delaminated (lower andorupper) crustal components (eg carbonates marls and meta-pelites) as well as terrigenous sediments entrained in theirmantle source

v) Early to Middle Miocene near primitive mafic (MHKS) lavas re-quire a heterogeneous (EM-II type) mantle source consisting ofcrust-contaminated subduction-modified metasomatized(veined) garnet lherzolitic mantle mixed with influxed as-thenosphere in back-arc mantle wedge Mixing of lower crustalsilicic melts with underplated mafic potassic magmas resultedin high-K calc-alkaline magmas and crustal contamination isalso present in the more evolved silicic rocks

vi) The disappearance of shoshonitic and ultrapotassic magmasprior to late Oligocene in the Western Anatolia extensionalprovince and the sudden occurrence of potassic activity duringEarly-Middle Miocene and abrupt change in the mantle can beexplained by direct addition of crustal rocks into the mantlesource of MHKS rocks via crustal delamination processes thatoccurred as a consequence of continental subduction Delami-nated crustal rocks and late arrival of subducted terrigenoussediments may explain many of the geochemical and isotopicsignatures and similarities between Simav MHKS rocks andhigh-K calc-alkaline series rocks

vii) The nature of the subducted and delaminated crustal materials(eg metapelites marlstone) also played a significant role inthe compositional variations of Early-Middle Miocene Simavmafic potassic magmas (eg shoshonite RPT-type lamproiteabsarokite)

viii) The origin of Early to Middle Miocene Simav magmatism canbe explained by the combined effects (shown in Fig 16) ofmultiple driving forces such as asthenospheric mantle flowsdelamination of subducting African mantle lithosphere fromaccreting crust trench retreat shallow continental subductionand consequent rapid uplift and extension and lithosphericdelamination processes The result was the simultaneous gen-eration of mafic potassic and high-K calc-alkaline magmas

ix) Based on (i) the development of regional uplifting and exten-sional stages (ii) abrupt change in mantle sources and (iii)sudden appearance of protruding (post-collisional) potassicmagmas during rapid tectonic transitions in Western Anatoliaback-arc setting it is inferred that the tectonic setting of firstpulses of post-collisional (Turkic-type) potassic magmas ap-pear as a tectonomagmatic tracker for the timing of last stageof regional uplifting and onset of extensional stages in differentperiods

Acknowledgement

This study was supported by TUumlBİTAK mdash CcedilAYDAG Project No106Y070 Additional support was obtained through the Istanbul Tech-nical University Research Fund (BAP Project No 32382) We expressour gratitude to Kale Maden Corp for their logistic support during thefield work in the summers of 2007 and 2008 We are very grateful toDr Drew Coleman of the University of North Carolina Chapel Hill andDr Marion Wampler of the Georgia State University for isotope mea-surements We also thank to Dr Alberto E Patino-Douce of the Uni-versity of Georgia Athens for the very productive review commentsand valuable suggestions We are also grateful for insightful com-ments provided by Dr Samuel Agostini and an anonymous reviewerthat significantly improved the manuscript and Dr Nelson Eby andDr Michael Roden for editorial help

References

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Aldanmaz E Pearce JA Thirwall MF Mitchell JG 2000 Petrogenetic evolution oflate Cenozoic post-collision volcanism in western Anatolia Turkey Journal of Vol-canology and Geothermal Research 102 67ndash95

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Alpaslan M Boztug D Frei R Temel A Kurt MA 2006 Geochemical and PbndashSrndashNdisotopic composition of the ultrapotassic volcanic rocks from the extension-relatedCamardi-Ulukisla basin Nigde Province Central Anatolia Turkey Journal of AsianEarth Science 27 613ndash627

Altherr R Topuz G Siebel W Şen C Meyer H-P Satır M Lahaye Y 2008 Geo-chemical and SrndashNdndashPb isotopic characteristics of Paleocene plagioleucitites fromthe Eastern Pontides (NE Turkey) Lithos 105 149ndash161

Altunkaynak Ş Genccedil C 2008 Petrogenesis and time-progressive evolution of the Ce-nozoic continental volcanism in the Biga Peninsula NW Anatolia (Turkey) Lithos102 316ndash340

Anderson DL 2005 Large igneous provinces delamination and fertile mantle Ele-ments 1 pp 271ndash275

Avanzinelli R Lustrino M Mattei M Melluso L Conticelli S 2009 Potassic andultrapotassic magmatism in the peri-Tyrrhenian region in the frame of the mantleevolution of the Central Mediterranean the role of sediment recycling at destruc-tive plate margin Lithos 113 213ndash227

Aydoğan MS Ccediloban H Bozcu M Akıncı O 2008 Geochemical and mantle-like iso-topic (Nd Sr) composition of the Baklan Granite from the Muratdağı Region(Banaz Uşak) Western Turkey implications for input of juvenile magmas in thesource domains of western Anatolia EocenendashMiocene granites Journal of AsianEarth Science 33 155ndash176

Barth MG McDonough WF Rudnick RL 2000 Tracking the budget of Nb and Ta inthe continental crust Chemical Geology 165 197ndash213

Beccaluva L Di Girolamo P Serri G 1991 Petrogenesis and tectonic setting of theRoman Province Italy Lithos 26 191ndash221

Benito R Loacutepez-Ruiz J Cebriaacute JM Hertogen J Doblas M Oyarzun R Demaiffe D1999 Sr and O isotope constraints on source and crustal contamination in thehigh-K calc-alkaline and shoshonitic Neogene volcanic rocks of SE Spain Lithos46 773ndash802

Bianchini G Beccaluva L Siena F 2008 Post-collisional and intraplate Cenozoic vol-canism in the rifted ApenninesAdriatic domain Lithos 101 125ndash140

Bingoumll E Delaloye M Ataman G 1982 Granitic intrusions in western Anatolia acontribution to the geodynamic study of this area Eclogae Geologicae Helvetiae2 437ndash446

Boari E Tommasini S Laurenzi MA Conticelli S 2009a Transition from ultrapotas-sic kamafugitic to sub-alkaline magmas Sr Nd and Pb isotope trace element and40Arndash39Ar age data from the Middle Latin Valley volcanic field Roman MagmaticProvince Journal of Petrology 50 1327ndash1357

Boari E Avanzinelli R Melluso L Giordano G Mattei M Mora V Conticelli S 2009bIsotope geochemistry (SrndashNdndashPb) and petrogenesis of leucite-bearing rocks fromldquoColli Albanirdquo volcano RomanMagmatic Province Central Italy inferences on volcanoevolution and magma genesis Bulletin of Volcanology 71 977ndash1005

Bozcu M 2010 Geology of Neogene basins of Buldan-Sarıcaova region and their im-portance in Western Anatolia neotectonics International Journal of Earth Science(Geol Rundsch) 99 851ndash860

Bozkurt E 2000 Timing of extension on the Buumlyuumlk Menderes graben western Turkeyand its tectonic implications In Bozkurt E Winchester JA Piper JDA (Eds)Tectonics and Magmatism in Turkey and the Surrounding Area Geologica Societyof London Special Publication 173 pp 385ndash403


Bozkurt E 2001 Late Alpine evolution of the central Menderes Massif Western Ana-tolia Turkey International Journal of Earth Science 89 728ndash744

Bozkurt E 2003 Origin of NE-trending basins in western Turkey Geodinamica Acta16 61ndash81

Bozkurt E Soumlzbilir H 2004 Tectonic evolution of the Gediz Graben field evidence foran episodic two stage extension in western Turkey Geological Magazine 14163ndash79

Bozkurt E Satır M Buğdaycıoğlu Ccedil 2011 Surprisingly young RbSr ages from theSimav extensional detachment fault zone northern Menderes Massif Turkey Jour-nal of Geodynamics 52 406ndash431

Brandon AD Goles GG 1995 Assessing subcontinental lithospheric mantle sourcesfor basalts Neogene volcanism in the Pacific Northwest USA as a test case Contri-bition Mineralogy Petrology 121 364ndash379

Buck WR Sokoutis D 1994 Analogue model of gravitational collapse and surface ex-tension during continental convergence Nature 369 737ndash740

Burchfiel BC Nakov R Dumurdzanov N Papanikolaou D Tzankov T Serafimovski TKing RW Kotzev V Todosov A Nurce B 2008 Evolution and dynamics of the Ce-nozoic tectonics of the South Balkan extensional system Geosphere 4 919ndash938

Carminati E Doglioni C 2004 EuropendashMediterranean tectonics Encyclopedia of Ge-ology Elsevier pp 135ndash146

Cavazza W Okay AI Zatin M 2009 Rapid early-middle Miocene exhumation of theKazdağ metamophic core complex (Western Anatolia) International Journal ofEarth Sciences 98 1935ndash1947

Cavazza W Federica I Okay AI Zatin M 2011 Apatite fission-track thermochro-nology of the Western Pontides (NW Turkey) Rapid Communication GeologicalMagazine pp 1ndash8

Ccediloban H 2007 Basalt magma genesis and fractionation in collision and extension re-lated provinces a comparison between eastern central and western AnatoliaEarth Science Reviews 80 219ndash238

Ccediloban H Flower MFJ 2006 Mineral phase compositions in silica undersaturatedlamproites from Bucak area (Isparta SW Turkey) Lithos 89 275ndash299

Ccediloban H Flower MFJ 2007 Late Pliocene lamproites from Bucak Isparta (south-western Turkey) implications for mantle lsquowedgersquo evolution during AfricandashAnato-lian plate convergence Journal of Asian Earth Science 29 160ndash176

Collins AS Robertson AHF 1999 Evolution of the Lycian Allochthon western Tur-key as north-facing Late Palaeozoic to Mesozoic rift and passive continental mar-gin Geological Journal 34 107ndash138

Conticelli S Carlson RW Widom E Serri G 2007 Chemical and isotopic composition(Os Pb Nd and Sr) of Neogene to Quaternary calc-alkalic shoshonitic and ultrapo-tassic mafic rocks from the Italian Peninsula inferences on the nature of their mantlesources Geological Society of America Special Papers 418 171ndash202

Conticelli S Guarnieri Li Farinelli A Mattei M Avanzinelli R Bianchini G BoariE Tommasini S Tiepolo M Prelevic D Venturelli G 2009a Trace elements andSrndashNdndashPb isotopes of K-rich shoshonitic and calc-alkaline magmatism of theWestern Mediterranean Region genesis of ultrapotassic to calc-alkaline magmaticassociations in a post-collisional geodynamic setting Lithos 107 68ndash92

Conticelli S Marchionni S Rosa D Giordano G Boari E Avanzinelli R 2009bShoshonite and sub-alkaline magmas from an ultrapotassic volcano SrndashNdndashPb iso-tope data on the Roccamonfina volcanic rocks Roman Magmatic Province South-ern Italy Contributions to Mineralogy and Petrology 157 41ndash63

Conticelli S Laurenzi M Giordano G Mattei M Avanzinelli R Melluso L Tomma-sini S Boari E Cifelli F Perini G 2010 Leucite-bearing (kamafugiticleucititic)and ndashfree (lamproitic) ultrapotassic rocks and associated shoshonites from Italyconstraints on petrogenesis and geodynamics Journal of the Virtual Explorer 3620 doi103809jvirtex201000251

Dallai L Freda C Gaeta M 2004 Oxygen isotope geochemistry of pyroclastic clino-pyroxene monitors carbonate contributions to Roman-type ultrapotassic magmasContributions to Mineralogy and Petrology 148 247ndash263

Di Renzo V Di Vito MA Arienzo I Carandente A Civetta L DAntonio M Gior-dano F Orsi G Tonarini S 2007 Magmatic history of Soma-Vesuvius on thebasis of New Geochemical and ısotopic data from a Deep Borehole (Camaldoli del-laTorre) Journal of Petrology 48 753ndash784

Doglioni C Carminati E Cuffaro M Scrocca D 2007 Subduction kinematics and dy-namic constraints Earth Science Reviews 83 125ndash175

Duggen S Hoernle K Bogaard VD Garbe-Schoumlnberg D 2005 Post-collisional tran-sition from subduction to intraplate-type magmatism in the Westernmost Medi-terranean evidence for continental-edge delamination of subcontinentallithosphere Journal of Petrology 46 (6) 1155ndash1201

Dumurdzanov N Serafimovski T Burchfiel BC 2005 Cenozoic tectonics of Macedo-nia and its relation to the South Balkan extensional regime Geosphere 1 1ndash22

Edwards MA Grasemann B 2009 Mediterranean snapshots of accelerated slab re-treat subduction instability in stalled continental collision The Geological SocietyLondon Special Publications 311 155ndash192

Elburg MA van Bergen MJ Foden JD 2004 Subducted upper and lower continen-tal crust contributes to magmatism in the collision sector of the Sunda-Banda arcIndonesia Geology 32 41ndash44

Endrun B Lebedev S Meier T Tirel C Friederich W 2011 Complex layered defor-mation within the Aegean crust and mantle revealed by seismic anisotropy NatureGeoscience 1065 203ndash207

Ercan T Guumlnay E Savaşccedilın MY 1982 Simav ve ccedilevresindeki Senozoyik yaşlı volka-nizmanın boumllgesel yorumlanması Bulletin of the Mineral Research and ExplorationInstitute of Turkey (MTA) 97 (98) 86ndash101

Ercan T Satir M Steinitz G Dora A Sarifakioglu E Adis C Walter H-J YildirimT 1995 Biga yarimadasi ile Goumlkccedileada Bozcaada ve Tavsan adalarindaki (KB Ana-dolu) Tersiyer volkanizmasinin ozellikleri Bulletin of the Mineral Research and Ex-ploration Institute of Turkey (MTA) 117 55ndash86 (in Turkish)

Ercan T Satır M Sevin D Tuumlrkecan A 1996 Evaluation of the recently conductedradiometric age measurements of the Tertiary and Quaternary-aged volcanicrocks located in Western Anatolia Bulletin of the Mineral Research and Explora-tion Institute of Turkey (MTA) 119 103ndash112 (in Turkish)

Erkuumll F Helvacı C Soumlzbilir H 2005 Evidence for two episodes of volcanism in theBigadic borate basin and tectonic implications for western Turkey Geological Jour-nal 40 545ndash570

Ersoy Y Helvacı C Soumlzbilir H Erkuumll F Bozkurt E 2008 A geochemical approach toNeogenendashQuaternary volcanic activity ofwestern Anatolia an example of episodic bi-modal volcanism within the Selendi Basin Turkey Chemical Geology 30 265ndash282

Ersoy Y Helvacı C Soumlzbilir H 2010 Tectono-stratigraphic evolution of the NEndashSW-trending superimposed Selendi basin implications for late Cenozoic crustal exten-sion in Western Anatolia Tectonophysics 488 210ndash232

Ersoy Y Helvacı C Palmer MR 2011 Stratigraphic structural and geochemical fea-tures of the NEndashSW trending Neogene volcano-sedimentary basins in western An-atolia Implications for associations of supra-detachment and transtensionalstrike-slip basin formation in extensional tectonic setting Journal of Asian EarthSciences 41 159ndash183

Eyuumlboğlu Y 2010 Late Cretaceous high‐K volcanism in the eastern Pontide orogenicbelt implications for the geodynamic evolution of NE Turkey International Geolo-gy Review 52 142ndash186

Faccenna C Jolivet L Piromallo C Morelli A 2003 Subduction and the depth ofconvection in the Mediterranean mantle Journal of Geophysical Research 108(B2) 2099 doi1010292001JB001690

Faccenna C Becker TW Lallemand S Lagabrielle Y Funiciello F Piromallo C2010 Subduction-triggered magmatic pulses a new class of plumes Earth andPlanetary Science Letters 299 54ndash68

Fengmei C Zhaochong Z Jingwen M Abudukadir P Lijin W Lianhui D HuishouYe Li C Rongfen Z 2006 Lamprophyre or Lamproite Dyke in the SW Tarimblock mdash discussion on the petrogenesis of these rocks and their source regionJournal of China University of Geosciences 17 13ndash24

Flower MFJ Hoang N Ccediloban H 2007 Collision-induced mantle flow as a driver ofextrusion tectonics a comparison of southeast Asia and the eastern Mediterra-nean Geophysical Research Abstracts 9 05923 SRef-ID1607ndash7692graEGU2007-A-05923

Foley SF 1992 Vein-plus-wall-rock melting mechanisms in the lithosphere and theorigin of potassic alkaline magmas Lithos 28 435ndash453

Foley SF Venturelli G Green DH Toscani L 1987 The ultrapotassic rocks charac-teristics classification and constraints for petrogenetic models Earth Science Re-views 24 81ndash134

Freda C Gaeta M Misiti V Mollo S Dolfi D Scarlato P 2008 Magmandashcarbonateinteraction an experimental study on ultrapotassic rocks from Alban Hills (CentralItaly) Lithos 101 397ndash415

Frezzotti ML De Astis G Dallai L Ghezzo C 2007 Coexisting calc-alkaline andultrapotassic magmatism at Monti Ernici Mid Latina Valley (Latium centralItaly) European Journal of Mineralogy 19 479ndash497

Fytikas M Giuliano O Innocenti F Marinelli G Mazzuoli R 1976 Geochronologi-cal data on recent magmatism of the Aegean sea Tectonophysics 31 T29ndashT34

Fytikas M Innocenti P Mazzuoli R Peccerillo A Villari L 1984 Tertiary to Quater-nary evolution of volcanism in the Aegean region In Dixon JE Robertson AHF(Eds) The Geological Evolution of the Eastern mediterranean 17 Special Publica-tion London Geological Society pp 687ndash700

Gesret A Laigle M Diaz J Sachpazi M Charalampakis M Hirn A 2011 Slab topdips resolved by teleseismic converted waves in the Hellenic subduction zoneGeophysical Research Letters 38 L20304 doi1010292011GL048996

Gill JB 1981 Orogenic Andesites and Plate Tectonics Springer Verlag Berlin 390 ppGudfinnsson GH Presnall DC 2005 Continuous gradations among primary carbona-

titic kimberlitic melilititic basaltic picritic and komatiitic melts in equilibriumwith garnet lherzolite at 3ndash8 GPa Journal of Petrology 46 1645ndash1659

Handley HK Turner S Macpherson CG Gertisser R Davidson JP 2011 HfndashNdisotope and trace element constraints on subduction inputs at island arcs limita-tions of Hf anomalies as sediment input indicators Earth and Planetary ScienceLetters 304 212ndash223

Harangi S Downes H Seghedi I 2006 TertiaryndashQuaternary subduction processesand related magmatism in the Alpine-Mediterranean region In Gee D Stephen-son R (Eds) European Lithosphere Dynamics Geological Society London Mem-oirs 32 pp 167ndash190

Harangi S Downes H Thirlwall M Gmeacuteling K 2007 Geochemistry Petrogenesis andGeodynamic Relationships of Miocene Calc-alkaline Volcanic Rocks in the WesternCarpathian Arc Eastern Central Europe Journal of Petrology 48 2261ndash2287

Hasoumlzbek A Akay E Erdoğan B Satır M Siebel W 2010 Early Miocene granite for-mation by detachment tectonics or not A case study from the northern MenderesMassif (Western Turkey) Journal of Geodynamics 50 67ndash80

Hofmann AW Jochum KP Seufert M White WM 1986 Nb and Pb in oceanic ba-salts new constraints on mantle evolution Earth and Planetary Science Letters 7933ndash45

Hooper PR Hawkesworth CJ 1993 Isotopic and geochemical constraints on the originand evolution of the Columbia River Basalts Journal of Petrology 34 1203ndash1246

Husson L Brun J-P Yamato P Faccenna C 2009 Episodic slab rollback fosters ex-humation of HPndashUHP rocks Geophysical Journal International 179 1292ndash1300

Iacono Marziano G Gaillard F Pichavant M 2008 Limestone assimilation by basalticmagmas an experimental re-assessment and application to Italian volcanoes Con-tributions to Mineralogy and Petrology 155 719ndash738

Innocenti F Agostini S Di Vincenzo G Doglioni C Manetti P Savaşccedilin MY Tonar-ini S 2005 Neogene and Quaternary volcanism in Western Anatolia magmasources and geodynamic evolution Marine Geology 397 397ndash421


Ionov DA Griffin WL OReilly SY 1997 Volatile-bearing minerals and lithophiletrace elements in the upper mantle Chemical Geology 141 153ndash184

Işık V Tekeli O 2001 Late orogenic crustal extension in the northern Menderes Mas-sif (Western Turkey) evidence for metamorphic core complex formation Interna-tional Journal of Earth Science 89 757ndash765

Işık V Seyitoğlu G Ccedilemen İ 2003 Ductile-brittle transition along the Alaşehir de-tachment fault and its structural relationship with the Simav detachment faultMenderes Massif western Turkey Tectonophysics 374 1ndash18

Işık V Tekeli O Seyitoğlu G 2004 The 40Ar39Ar age of extensional ductile deforma-tion and granitoid intrusions in the northern Menderes core complex implicationsfor the initiation of extensional tectonics in western Turkey Journal of Asian EarthScience 23 555ndash566

Johnson MC Plank T 1999 Dehydration and melting experiments constrain the fateof subducted sediments Geochemistry Geophysics Geosystems 1 GC000014

Karacık Z Yılmaz Y Pearce JA 2007 The Dikili-Ccedilandarlı volcanics Western Turkeymagmatic interactions as recorded by petrographic and geochemical featuresTurkish Journal of Earth Sciences 16 493ndash522

Karacık Z Yılmaz Y Pearce JA Ece I 2008 Petrochemistry of the south Marmaragranitoids northwest Anatolia Turkey International Journal of Earth Science(Geol Rundsch) 97 1181ndash1200

Karaoğlu Ouml Helvacı C Ersoy Y 2010 Petrogenesis and 40Ar39Ar geochronology ofthe volcanic rocks of the Uşak-Guumlre basin western Tuumlrkiye Lithos 19 193ndash210

Kay SM Copeland P 2006 Early to middle Miocene back-arc magmas of the Neu-queacuten Basin geochemical consequences of slab shallowing and the westwarddrift of South America Geological Society of America Special Paper 407 185ndash213

Kay RW Kay SM 1993 Delamination and delamination magmatism Tectonophy-sics 219 177ndash189

Koccedilyiğit A Yusufoğlu H Bozkurt E 1999 Evidence from the Gediz Graben for epi-sodic two-stage extension in western Turkey Journal of Geological Society of Lon-don 156 605ndash616

Koumlpruumlbaşı N Aldanmaz E 2004 Geochemical constraints on the petrogenesis of Ce-nozoic I-type granitoids in Northwest Anatolia Turkey evidence for magma gen-eration by lithospheric delamination in a post-collisional setting InternationalGeology Review 46 705ndash729

Kovaacutecs I Falus Gy Stuart G Hidas K Szaboacute Cs Flower MFJ Hegedűs E PosgayK Zilahi-Sebess L 2012 Seismic anisotropy and deformation patterns in uppermantle xenoliths from the central Carpathian-Pannonian region Asthenosphericflow as a driving force for Cenozoic extension and extrusion Tectonophysics514ndash517 168ndash179

Krmiacuteček L Cempiacuterek J Havliacuten A Přichystal A Houzar S Krmiacutečkovaacute M Gadas P2011 Mineralogy and petrogenesis of a BandashTindashZr-rich peralkaline dyke from Šeb-kovice (Czech Republic) recognition of the most lamproitic Variscan intrusionLithos 121 74ndash86

Le Bas MJ Le Maitre RW Streckeisen A Zanettin B 1986 A chemical classificationof volcanic rocks based on the total alkali-silica diagram Journal of Petrology 27745ndash750

Lips ALW Cassard D Soumlzbilir H Yılmaz H 2001 Multistage exhumation of theMenderes Massif western Anatolia (Turkey) International Journal of Earth Science89 781ndash792

Lustrino M Morra V Fedele L Serracino M 2007 The transition between lsquoorogenicrsquoand lsquoanorogenicrsquo magmatism in the western Mediterranean area the Middle Mio-cene volcanic rocks of Isola del Toro (SW Sardinia Italy) Terra Nova 19 148ndash159

Marchev P Raicheva R Downes H Vasellic O Chiaradiad M Moritz R 2004 Com-positional diversity of EocenendashOligocene basaltic magmatism in the Eastern Rho-dopes SE Bulgaria implications for genesis and tectonic setting Tectonophysics393 301ndash328

Marotta AM Fernandez M Sabadini R 1999 The onset of extension during litho-spheric shortening a two-dimensional thermomechanical model for lithosphericunrooting Geophysical Journal International 139 98ndash114

Meissner R Money W 1998 Weakness of the lower continental crust a condition fordelamination uplift and escape Tectonophysics 296 47ndash60

Mollo S Gaeta M Freda C Di Rocco T Misiti V Scarlato P 2010 Carbonate assimila-tion inmagmas a reappraisal based on experimental petrology Lithos 114 503ndash514

Mutlu AK Karabulut H 2011 Anisotropic Pn tomography of Turkey and adjacent re-gions Geophysical Journal International 187 1743ndash1758

Nikogosian IK van Bergen MJ 2010 Heterogeneous mantle sources of potassium-rich magmas in central-southern Italy melt inclusion evidence from Roccamonfinaand Ernici (Mid Latina Valley) Journal of Volcanology and Geothermal Research197 279ndash302

OReilly SY Griffin WL 2000 Apatite in the mantle implications for metasomaticprocesses and high heat production in Phanerozoic mantle Lithos 53 217ndash232

Oberhaumlnsli R Candan O Dora OOuml Duumlrr S 1997 Eclogites within the MenderesMassif western Turkey Lithos 41 135ndash150

OBrien HE Irving AJ McCallum IS Thirlwall MF 1995 Strontium neodymium andlead isotopic evidence for the interaction of post-suhduction asthenospheric po-tassic mafic magmas of the Highwood Mountains Montana USA with ancientWyoming craton lithospheric mantle Geochimica et Cosmochimica Acta 594539ndash4556

Okay AI Monod O Monieacute P 2002 Triassic blueschists and eclogites from northwestTurkey vestiges of the Paleo-Tethyan subduction Lithos 64 155ndash178

Okay AI Satır M Zattin M Cavazza W Topuz G 2008 An Oligocene ductile strike-slip shear zone The Uludağ Massif northwest Turkey mdash implications for the west-ward translation of Anatolia Geological Society of America GSA Bulletin 120doi101130B262291

Papanikolau D 2010 Major plaogeographic tectonic and geodynamic changes fromthe last stage of Hellenides to the actual Hellenic arc and trench system Bulletin

of the Geological Society of Greece 2010 Proceedings of the 12th InternationalCongress Patras May XLIII No-1 pp 71ndash95

Pearce FD Rondenay S Chen C Suckale J Sachpazi M Charalampakis M Hosa ARoyden L 2009 High-resolution seismic imaging of mantle-wedge structureacross northern and southern segments of the western Hellenic subduction zoneAmerican Geophysical Union Fall Meeting abstract T43E-04

Peccerillo A 2005 Plio-Quaternary volcanism in Italy Petrology Geochemistry Geo-dynamics Springer Berlin Heidelberg New York 365 pp

Peccerillo A Martinotti G 2006 The Western Mediterranean lamproitic magmatismorigin and geodynamic significance Terra Nova 18 109ndash117

Peccerillo A Taylor SR 1976 Geochemistry of Eocene calcalkaline volcanic rocks ofthe Kastamonu area northern Turkey Contributions to Mineralogy and Petrology58 63ndash81

Peccerillo A Federico M Barbieri M Brilli M Wu T-W 2010 Interaction betweenultrapotassic magmas and carbonate rocks evidence from geochemical and isoto-pic (Sr Nd O) compositions of granular lithic clasts from the Alban Hills VolcanoCentral Italy Geochimica et Cosmochimica Acta 74 2999ndash3022

Pe-Piper G 1994 Lead isotopic compositions of Neogene volcanic rocks from the Ae-gean extensional area Chemical Geology 118 27ndash41

Pe-Piper G Piper DJW 2001 Late Cenozoic post-collisional Aegean igneous rocksNd Pb and Sr isotopic constraints on petrogenetic and tectonic models GeologicalMagazine 138 653ndash668

Pe-Piper G Piper DJW 2007 Neogene back-arc volcanism of the Aegean new in-sights into the relationship between magmatism and tectonics Geological Societyof America Special Paper 418 7ndash31

Plank T 2005 Constraints from thoriumlanthanum on sediment recycling at subduc-tion zones and the evolution of the continents Journal of Petrology 46 921ndash944

Plank T Langmuir CH 1998 The chemical composition of subducting sediment andits consequences for the crust and mantle Chemical Geology 145 325ndash394

Prelevic D Foley SF Romer R Conticelli S 2008 Mediterranean Tertiary lam-proites derived from multiple source components in postcollisional geodynamicsGeochimica et Cosmochimica Acta 72 2125ndash2156

Prelevic D Akal C Romer R Foley SF 2010 Lamproites as indicators of accretionandor shallow subduction in the assembly of Southwestern Anatolia TurkeyTerra Nova 22 443ndash452

Purvis M Robertson AHF 2004 A pulsed extension model for the NeogenendashRecentEndashW-trending Alaşehir (Gediz) Graben and the NWndashSE trending Selendi andGoumlrdes Basins E Turkey Tectonophysics 391 171ndash201

Purvis M Robertson A 2005 Sedimentation of the NeogenendashRecent Alaşehir (Gediz)continental graben system used to test alternative tectonic models for western(Aegean) Turkey Sedimentary Geology 173 373ndash408

Ring U Collins AS 2005 UndashPb Sims dating of synkinematic granites timing of core-complex formation in the northern Anatolide belt of western Turkey Journal of theGeological Society London 162 289ndash298

Royden LH Papanikolaou DJ 2011 Slab segmentation and late Cenozoic disruptionof the Hellenic arc Geochemistry Geophysics Geosystems 12 Q03010doi1010292010GC003280

Rudnick RL Gao S 2004 Composition of the Continental Crust In Rudnick RL(Ed) Treatise on Geochemistry Elsevier-Pergamon Oxford pp 1ndash64

Schott B Schmeling H 1998 Delamination and detachment of a lithospheric rootTectonophysics 296 225ndash247

Semiz B Ccediloban H Roden MF Oumlzpınar Y Flower MFJ McGregor H in press Min-eral composition in cognate inclusions in Late Miocene -Early Pliocene potassiclamprophyres with affinities to lamproites from the Denizli region Western Ana-tolia Turkey Implications for uppermost mantle processes in a back-arc settingLithos doi101016jlithos201201005

Şengoumlr AMC Yilmaz Y 1981 Tethyan evolution of Turkey a plate tectonic ap-proach Tectonophysics 75 181ndash241

Seyitoğlu G 1997 The Simav graben an example of EndashW trending structures in theLate Cenozoic extensional system of Western Turkey Turkish Journal of Earth Sci-ence 6 135ndash141

Seyitoğlu G Anderson D Nowell G Scott B 1997 The evolution from Miocene po-tassic to Quaternary sodic magmatism in western Turkey implications for enrich-ment processes in the lithospheric mantle Journal of Volcanology and GeothermalResearch 76 127ndash147

Seyitoğlu G Işık V Ccedilemen İ 2004 Complete Tertiary exhumation history of theMenderes Massif western Turkey an alternative working hypothesis Terra Nova16 358ndash364

Shimoda G Tatsumi Y Morishita Y 2003 Behavior of subducting sediments be-neath an arc under a high geothermal gradient constraints from the MioceneSW Japan arc Geochemical Journal 37 503ndash518

Sims KWW De Paolo DJ 1997 Inferences about mantle magma sources from in-compatible element concentration ratios in oceanic basalts Geochimica et Cosmo-chimica Acta 61 765ndash784

Sodoudi F Kind R Hatzfeld D Priestley K Hanka W Wylegalla K Stavrakakis GVafidis A Harjes H-P Bohnhoff M 2006 Lithospheric structure of the Aegeanobtained from P and S receiver functions Journal of Geophysical Research 111B12307 doi1010292005JB003932

Stracke A Hofmann AW Hart SR 2005 FOZO HIMU and the rest of the Mantle ZooG-Cubed 6 2004GC000824 pp 1ndash20

Sun S-S McDonough WF 1989 Chemical and isotopic systematics of oceanic ba-salts Implications for mantle composition and processes In Sunders ADNorry MJ (Eds) Magmatism in the Ocean Basins Blackwell Scientific Bostonpp 313ndash345

Tappe S Foley SF Jenner GA Heaman LM Kjarsgaard BA Romer RL Stracke AJoyce N Hoefs J 2006 Genesis of ultramafic lamprophyres and carbonatites at


Aillik Bay Labrador a consequence of incipient lithospheric thinning beneath theNorth Atlantic craton Journal of Petrology 47 1261ndash1315

Taylor SR McLennan SM 1985 The Continental Crust Its Composition and Evolu-tion Blackwell Oxford

Thomsen TB Schmidt MW 2008 Melting of carbonated pelites at 25ndash50 GPa sili-catendashcarbonatite liquid immiscibility and potassiumndashcarbon metasomatism of themantle Earth and Planetary Science Letters 267 17ndash31

Thomson SN Ring U 2006 Thermochronologic evaluation of postcollision extensionin the Anatolid orogen western Turkey Tectonics 25 TC3005 doi1010292005TC001833

Tommasini S Avanzinelli R Conticelli S 2011 The ThLa and SmLa conundrumof the Tethyan realm lamproites Earth and Planetary Science Letters 301469ndash478

Tonarini S Agostini S Innocenti F Manetti P 2005 δ11B as tracer of slab dehydra-tion and mantle evolution in Western Anatolia Cenozoic magmatism Terra Nova17 259ndash264

van Hinsbergen DJJ 2010 A key extensional metamorphic complex reviewed and re-stored the Menderes Massif of western Turkey Earth Science Reviews 102 60ndash76

van Hinsbergen DJJ Kaymakci N Spakman W Torsvik TH 2010a Reconciling thegeological history of western Turkey with plate circuits and mantle tomographyEarth and Planetary Science Letter 297 674ndash686

van Hinsbergen DJJ Dekkers MJ Bozkurt E Kopman M 2010b Exhumation witha twist paleomagnetic constraints on the evolution of the Menderes metamorphiccore complex western Turkey Tectonics 29 doi1010292009TC002596

Vervoort JD Patchett PJ Blichert-Toft J Albarede F 1999 Relationships betweenLundashHf and SmndashNd isotopic systems in the global sedimentary system Earth andPlanetary Science Letters 168 79ndash99

Wang K Plank T Walker JD Smith EI 2002 A mantle melting profile across thebasin and range SWUSA Journal of Geophysical Research-Solid Earth 107doi1010292001JB0002092

Weldeab S Emeis K-C Hemleben C Siebel W 2002 Provenance of lithogenic sur-face sediments and pathways of riverine suspended matter in the Eastern Mediter-ranean Sea evidence from 143Nd144Nd and 87Sr86Sr ratios Chemical Geology 186139ndash149

Westaway R Pringle M Yurtmen S Demir T Bridgland D Rowbotham G MaddyD 2004 Pliocene and Quaternary regional uplift in western Turkey the GedizRiver terrace staircase and the volcanism at Kula Tectonophysics 391 121ndash169

Willbold M Stracke A 2010 Formation of enriched mantle components by recyclingof upper and lower continental crust Chemical Geology 76 188ndash197

Wilson M Bianchini G 1999 TertiaryndashQuaternary magmatism within the Mediterra-nean and surrounding regions Geological Society of London Special Publications156 141ndash168

Wood DA Joron J-L Treuil M Nony M Tarney J 1979 Elemental and Sr isotopevariations in basic lavas from Iceland and the surrounding ocean floor The natureof mantle source inhornogeneities Contributions to Mineralogy and Petrology 70319ndash339

Yılmaz K 2010 Origin of anorogenic lsquolamproite-likersquo potassic lavas from Denizli re-gion Western Anatolia Extensional Province Turkey Mineralogy and Petrology99 219ndash239

Zhang Z Xiao X Wang J Wang Y Kusky TM 2008 Post-collisional Plio-Pleistocene shoshonitic volcanism in the western Kunlun Mountains NW Chinageochemical constraints on mantle source characteristics and petrogenesis Journalof Asian Earth Sciences 31 379ndash403

Zhu L Mitchell BJ Akyol N Ccedilemen I Kekovali K 2006 Crustal thickness variationsin the Aegean region and implications for the extension of continental crust Jour-nal of Geophysical Research 111 B01301 doi1010292005JB003770

Zindler A Hart S 1986 Chemical geodynamics Annual Reviews of Earth and Plane-tary Sciences 14 493ndash571


Aldanmaz et al 2000 Innocenti et al 2005 Pe-Piper and Piper 20012007 Seyitoğlu et al 1997) Following Late Cretaceous to Early Eo-cene compressive deformation along with propagating diverse geo-dynamic processes such as asthenospheric mantle flows trench-retreat roll-back of the Aegean slab regional uplift (exhumation ofthe Menderes Massif) and extensional tectonic the WAEP hosted dis-tinct (low-K to high-K calc-alkaline and medium-K to high-K alka-line) magma series (eg Agostini et al 2007 2010 Akay 2008Altunkaynak and Genccedil 2008 Ersoy et al 2008 Innocenti et al2005 Pe-Piper and Piper 2001 2007) In contrast to the subalkalineand transitional affinity of magmatism during Middle EocenendashLateOligocene time (eg Altunkaynak and Genccedil 2008 Ercan et al1995 Karacık et al 2007 2008 Koumlpruumlbaşı and Aldanmaz 2004)the Early to Middle Miocene period is characterized by the appear-ance of almost contemporaneous mafic potassic and high-K calc-alkaline magmas in a post-collisional intra-plate (back-arc) exten-sional setting In this geodynamic setting mantle heterogeneity andthe nature of mantle sources also require a particular interest

Here we focus on the Simav (Kuumltahya) mdash Uşak region of WesternAnatolia where mafic and intermediate-silicic members of Early-Middle Miocene mafic potassic and high-K calc-alkaline magmaswere formed contemporaneously in the same tensional tectonic envi-ronment Volcanic and plutonic rocks around the Simav graben pro-vide some data critical to the understanding of the evolution of thegeotectonic environment and magmatic patterns (eg intra-plate po-tassic magmas) of the Aegean region Since the Simav mafic potassicvolcanic rocks represent rather primitive mantle-derivedmelts a pet-rological study of the Simav magmatism may also provide useful in-formation for better understanding of the geodynamic processesassociated with a back-arc setting Here we document systematic re-search on KndashAr chronology geochemistry and particularly Sr Ndand Pb isotope compositions of Early to Middle Miocene magmaticrocks in the Simav region to explain how coevally generated maficpotassic and high-K calc-alkaline (post-collisional) magma pulsesoccur in the same geodynamic tectonic setting We also provide con-straints on the tectono-magmatic setting and compositional charac-teristics of strongly potassic magmas

2 Geological background

Structural magmatic and metamorphic records from Simav andsurrounding regions in the seismically active Western Anatolia(back-arc) extensional province have been reported by severalworkers during the last decade (eg Akay 2008 Bozkurt andSoumlzbilir 2004 Ersoy et al 2008 2010 Hasoumlzbek et al 2010Innocenti et al 2005 Işık et al 2003 2004 Karaoğlu et al 2010Purvis and Robertson 2004 Ring and Collins 2005 Seyitoğlu 1997Seyitoğlu et al 1997 2004 Thomson and Ring 2006)

The Simav region in Central Western Anatolia is located betweenthe İzmir-Ankara Neotethyan suture zone to the north (Şengoumlr andYilmaz 1981) and the Taurides (Lycian Nappes) to the south (egCollins and Robertson 1999) (Fig 1) Basement rocks in the regionare represented by several rock groups of the Menderes Massif andthe Afyon zone (Akdeniz and Konak 1979) (Fig 1) The MenderesMassif is a NEndashSW trending large-scale dome-shaped metamorphiccore complex interpreted as the eastward continuation of the Cyclad-ic Massif in the Aegean Sea (eg Oberhaumlnsli et al 1997) The Mende-res block collided with Sakarya prior to 50 Ma ago followed byregional high-temperature (HT) metamorphism and granitic intru-sions (van Hinsbergen et al 2010b) The exhumation of the Mende-res Massif occurred along the successive detachment faults duringthe Neogene period Recent studies show that the Menderes Massifhas experienced a two- or multi-stage exhumation process (Lips etal 2001 Seyitoğlu et al 2004) The first stage of exhumation of theMenderes Massif occurred between the late Oligocene (25 Ma) andthe Middle Miocene (16 Ma) (Seyitoğlu et al 2004) perhaps chiefly

in the latest Oligocene (Purvis and Robertson 2005) or in latest Oli-gocene to earliest Miocene time (eg Cavazza et al 2009) Agostiniet al (2010) interpreted the uplifting and exhumation of the Mende-res Massif basement rocks as a consequences of extensional grabensand transtrensional fault systems Accordingly Bozkurt et al (2011)suggested the beginning of extensional exhumation of the northernMenderes Massif during Late Oligocene (30 Ma) Cavazza et al(2011) proposed that extension affecting the Aegean region gaverise to exhumation at a regional scale Some studies also suggestthat there are apparent links i) between Early-Middle Miocene exten-sion and roll-back of the Aegean trench and ii) Late MiocenendashPlio-Quaternary extension and the onset of the roll-back of the subductedAegean slab in Western Anatolia (eg Burchfiel et al 2008Dumurdzanov et al 2005 Papanikolau 2010 Royden andPapanikolaou 2011) The timing and cause of extension of the Aegeangrabens are discussed by Bozkurt and Soumlzbilir (2004 and referencesthere in) Ersoy et al (2010) van Hinsbergen (2010) and vanHinsbergen et al (2010a 2010b)

Three main EndashW trending grabens which are called the SimavGediz and Buumlyuumlk Menderes grabens divide the Menderes Massifinto subunits (Fig 1) Tectonic evolution of the graben-type basinsin Western Anatolia was governed by episodic (eg Bozkurt 20002001 2003 Ersoy et al 2010 Koccedilyiğit et al 1999) or pulsed exten-sional forces (Bozcu 2010 Purvis and Robertson 2004 2005) duringthe late Cenozoic These basins host intraplate (post-collisional)magmas

The Simav graben is a PliocenendashQuaternary structure with a dis-tinct topographical depression extending for about 150 km (Fig 2)The graben cuts the NEndashSW trending Demirci Selendi and Akdere ba-sins and is regarded as one of the latest products of NndashS extensionaltectonics in contrast to the Aegean grabens that began to developduring late OligocenendashEarly Miocene times (Seyitoğlu et al 1997)The southern side of the Simav half-graben cut the Neogene basinsand also the Simav detachment fault Bozkurt et al (2011) suggestedan episodic Simav detachment fault activity between ca 30 and 8 MaBased on the age of the granitoids and the mylonitic deformation ofthe Eğrigoumlz granitoid some workers (Işık and Tekeli 2001 Işık etal 2004 Ring and Collins 2005 Thomson and Ring 2006) suggestedthat the extensional tectonics of Western Anatolia began before EarlyMiocene times and represents an early stage in the Tertiary exten-sional tectonics of Western Turkey Cavazza et al (2009) suggestedthat the Neogene extensional tectonism in the northern Aegean re-gion has been episodic with accelerated pulses in the Early-MiddleMiocene and Plio-Quaternary

Sedimentation in the basins began with fluvial conglomerates andcontinued with approximately 200 m of fluvial sediments and lime-stones which alternate with volcanic products upwards in the section(Akdeniz and Konak 1979 Ercan et al 1982 Ersoy et al 2010)(Fig 2) The age of the sediments is accepted to be early Mioceneon the basis of radiometric age data (ranging between 242 Ma and149 Ma) from the volcanic intercalations (eg Ercan et al 1996Ersoy et al 2011 Purvis and Robertson 2004 2005 Seyitoğlu et al1997) Ersoy et al (2010) indicated that the crustal extensionresulted in the exhumation of the mid-crustal units (the MenderesMassif) synchronously with volcano-sedimentary basin formation

As summary the occurrence of volcanic rocks intercalated withsediments in graben-type structures and extensional uplifting ofthe region shows that (Early to Middle Miocene) magmatism inSimav region took place under an extensional tectonic regime in aback-arc position

3 Analytical methods

Approximately 70 rock samples were collected from representa-tive sections of all magmatic units in the study area during fieldworkThin sections of these rock samples were prepared in the Istanbul











Sampleno








()b (nmolkg)



























Table 2 (continued)





REE (ppm)496 412 476 297 338 385907 721 893 524 531 6561018 884 1043 663 728 794383 337 371 212 267 253653 62 695 455 479 49145 136 15 034 04 087508 44 478 294 377 304494 457 446 31 366 337286 283 259 194 203 188089 085 091 06 062 066095 098 094 065 07 065042 04 042 032 034 032271 257 245 19 211 189042 041 038 033 032 032

0707993 0708129 0712587 07124950512374 0512350 0512318 05123211900456 1911042 1885700 18877771571824 1582716 1575400 15789213912738 3950228 3921000 3931769





Table 2 (continued)



Daciterhyolite









Table 2 (continued)

206plusmn05



150 233 215 172 222 173 215 232 228 242 51781 1157 865 949 1127 847 440 404 519 1139 281157 163 149 176 163 168 996 1106 160 101 19432 41 26 28 43 16 34 25 51 40 1028 41 27 32 41 2 62 48 61 9 248 615 48 82 27 75 41 78 48 50 2021 33 23 25 30 10 48 44 41 100 16164 155 142 155 165 169 237 2176 295 320 14024 20 206 23 194 22 354 44 52 396 346143 11 105 14 119 154 21 221 224 136 12145 142 135 142 154 154 192 181 205 22 1955 52 45 52 54 48 69 63 87 88 4337 34 38 33 35 8 89 59 52 7 1712 08 11 13 09 15 2 19 23 099 111821 186 228 253 375 197 30 14 478 268 14495 32 26 51 53 31 65 6 112 18 212

REE (ppm)393 534 629 415 528 355 29 109 152 588 289706 921 1092 754 941 639 55 233 373 123 585781 983 1165 84 1037 707 657 376 575 135 604273 341 393 249 333 236 262 195 261 52 214505 506 577 506 56 429 583 538 76 113 466071 098 08 073 095 068 079 071 098 206 0477306 294 347 335 308 295 554 66 71 967 397371 316 34 342 302 359 553 686 801 77 556223 178 181 214 182 215 331 429 525 397 376069 058 063 063 062 065 097 116 145 142 07908 063 065 078 066 07 117 144 176 143 124043 027 03 037 03 035 051 064 085 0559 0556239 175 179 244 183 226 323 407 494 35 333036 027 029 036 03 038 051 063 079 0535 0482

0709653 0709624 0709075 070988 07097 071655 0774180512354 0512398 0512379 051386 05123 051218 0512271891615 18840 18876 18942 18891 18604 19281157253 15685 15716 15721 15692 15703 1573391255 38952 39026 3907 38962 3967 39098

































































10 Conclusions













Acknowledgement


References















































































































































































Sampleno








()b (nmolkg)



























Table 2 (continued)





REE (ppm)496 412 476 297 338 385907 721 893 524 531 6561018 884 1043 663 728 794383 337 371 212 267 253653 62 695 455 479 49145 136 15 034 04 087508 44 478 294 377 304494 457 446 31 366 337286 283 259 194 203 188089 085 091 06 062 066095 098 094 065 07 065042 04 042 032 034 032271 257 245 19 211 189042 041 038 033 032 032

0707993 0708129 0712587 07124950512374 0512350 0512318 05123211900456 1911042 1885700 18877771571824 1582716 1575400 15789213912738 3950228 3921000 3931769





Table 2 (continued)



Daciterhyolite









Table 2 (continued)

206plusmn05



150 233 215 172 222 173 215 232 228 242 51781 1157 865 949 1127 847 440 404 519 1139 281157 163 149 176 163 168 996 1106 160 101 19432 41 26 28 43 16 34 25 51 40 1028 41 27 32 41 2 62 48 61 9 248 615 48 82 27 75 41 78 48 50 2021 33 23 25 30 10 48 44 41 100 16164 155 142 155 165 169 237 2176 295 320 14024 20 206 23 194 22 354 44 52 396 346143 11 105 14 119 154 21 221 224 136 12145 142 135 142 154 154 192 181 205 22 1955 52 45 52 54 48 69 63 87 88 4337 34 38 33 35 8 89 59 52 7 1712 08 11 13 09 15 2 19 23 099 111821 186 228 253 375 197 30 14 478 268 14495 32 26 51 53 31 65 6 112 18 212

REE (ppm)393 534 629 415 528 355 29 109 152 588 289706 921 1092 754 941 639 55 233 373 123 585781 983 1165 84 1037 707 657 376 575 135 604273 341 393 249 333 236 262 195 261 52 214505 506 577 506 56 429 583 538 76 113 466071 098 08 073 095 068 079 071 098 206 0477306 294 347 335 308 295 554 66 71 967 397371 316 34 342 302 359 553 686 801 77 556223 178 181 214 182 215 331 429 525 397 376069 058 063 063 062 065 097 116 145 142 07908 063 065 078 066 07 117 144 176 143 124043 027 03 037 03 035 051 064 085 0559 0556239 175 179 244 183 226 323 407 494 35 333036 027 029 036 03 038 051 063 079 0535 0482

0709653 0709624 0709075 070988 07097 071655 0774180512354 0512398 0512379 051386 05123 051218 0512271891615 18840 18876 18942 18891 18604 19281157253 15685 15716 15721 15692 15703 1573391255 38952 39026 3907 38962 3967 39098

































































10 Conclusions













Acknowledgement


References






























































































































































































Table 2 (continued)





REE (ppm)496 412 476 297 338 385907 721 893 524 531 6561018 884 1043 663 728 794383 337 371 212 267 253653 62 695 455 479 49145 136 15 034 04 087508 44 478 294 377 304494 457 446 31 366 337286 283 259 194 203 188089 085 091 06 062 066095 098 094 065 07 065042 04 042 032 034 032271 257 245 19 211 189042 041 038 033 032 032

0707993 0708129 0712587 07124950512374 0512350 0512318 05123211900456 1911042 1885700 18877771571824 1582716 1575400 15789213912738 3950228 3921000 3931769





Table 2 (continued)



Daciterhyolite









Table 2 (continued)

206plusmn05



150 233 215 172 222 173 215 232 228 242 51781 1157 865 949 1127 847 440 404 519 1139 281157 163 149 176 163 168 996 1106 160 101 19432 41 26 28 43 16 34 25 51 40 1028 41 27 32 41 2 62 48 61 9 248 615 48 82 27 75 41 78 48 50 2021 33 23 25 30 10 48 44 41 100 16164 155 142 155 165 169 237 2176 295 320 14024 20 206 23 194 22 354 44 52 396 346143 11 105 14 119 154 21 221 224 136 12145 142 135 142 154 154 192 181 205 22 1955 52 45 52 54 48 69 63 87 88 4337 34 38 33 35 8 89 59 52 7 1712 08 11 13 09 15 2 19 23 099 111821 186 228 253 375 197 30 14 478 268 14495 32 26 51 53 31 65 6 112 18 212

REE (ppm)393 534 629 415 528 355 29 109 152 588 289706 921 1092 754 941 639 55 233 373 123 585781 983 1165 84 1037 707 657 376 575 135 604273 341 393 249 333 236 262 195 261 52 214505 506 577 506 56 429 583 538 76 113 466071 098 08 073 095 068 079 071 098 206 0477306 294 347 335 308 295 554 66 71 967 397371 316 34 342 302 359 553 686 801 77 556223 178 181 214 182 215 331 429 525 397 376069 058 063 063 062 065 097 116 145 142 07908 063 065 078 066 07 117 144 176 143 124043 027 03 037 03 035 051 064 085 0559 0556239 175 179 244 183 226 323 407 494 35 333036 027 029 036 03 038 051 063 079 0535 0482

0709653 0709624 0709075 070988 07097 071655 0774180512354 0512398 0512379 051386 05123 051218 0512271891615 18840 18876 18942 18891 18604 19281157253 15685 15716 15721 15692 15703 1573391255 38952 39026 3907 38962 3967 39098

































































10 Conclusions













Acknowledgement


References





































































































































































Table 2 (continued)



Daciterhyolite









Table 2 (continued)

206plusmn05



150 233 215 172 222 173 215 232 228 242 51781 1157 865 949 1127 847 440 404 519 1139 281157 163 149 176 163 168 996 1106 160 101 19432 41 26 28 43 16 34 25 51 40 1028 41 27 32 41 2 62 48 61 9 248 615 48 82 27 75 41 78 48 50 2021 33 23 25 30 10 48 44 41 100 16164 155 142 155 165 169 237 2176 295 320 14024 20 206 23 194 22 354 44 52 396 346143 11 105 14 119 154 21 221 224 136 12145 142 135 142 154 154 192 181 205 22 1955 52 45 52 54 48 69 63 87 88 4337 34 38 33 35 8 89 59 52 7 1712 08 11 13 09 15 2 19 23 099 111821 186 228 253 375 197 30 14 478 268 14495 32 26 51 53 31 65 6 112 18 212

REE (ppm)393 534 629 415 528 355 29 109 152 588 289706 921 1092 754 941 639 55 233 373 123 585781 983 1165 84 1037 707 657 376 575 135 604273 341 393 249 333 236 262 195 261 52 214505 506 577 506 56 429 583 538 76 113 466071 098 08 073 095 068 079 071 098 206 0477306 294 347 335 308 295 554 66 71 967 397371 316 34 342 302 359 553 686 801 77 556223 178 181 214 182 215 331 429 525 397 376069 058 063 063 062 065 097 116 145 142 07908 063 065 078 066 07 117 144 176 143 124043 027 03 037 03 035 051 064 085 0559 0556239 175 179 244 183 226 323 407 494 35 333036 027 029 036 03 038 051 063 079 0535 0482

0709653 0709624 0709075 070988 07097 071655 0774180512354 0512398 0512379 051386 05123 051218 0512271891615 18840 18876 18942 18891 18604 19281157253 15685 15716 15721 15692 15703 1573391255 38952 39026 3907 38962 3967 39098

































































10 Conclusions













Acknowledgement


References





































































































































































Table 2 (continued)

206plusmn05



150 233 215 172 222 173 215 232 228 242 51781 1157 865 949 1127 847 440 404 519 1139 281157 163 149 176 163 168 996 1106 160 101 19432 41 26 28 43 16 34 25 51 40 1028 41 27 32 41 2 62 48 61 9 248 615 48 82 27 75 41 78 48 50 2021 33 23 25 30 10 48 44 41 100 16164 155 142 155 165 169 237 2176 295 320 14024 20 206 23 194 22 354 44 52 396 346143 11 105 14 119 154 21 221 224 136 12145 142 135 142 154 154 192 181 205 22 1955 52 45 52 54 48 69 63 87 88 4337 34 38 33 35 8 89 59 52 7 1712 08 11 13 09 15 2 19 23 099 111821 186 228 253 375 197 30 14 478 268 14495 32 26 51 53 31 65 6 112 18 212

REE (ppm)393 534 629 415 528 355 29 109 152 588 289706 921 1092 754 941 639 55 233 373 123 585781 983 1165 84 1037 707 657 376 575 135 604273 341 393 249 333 236 262 195 261 52 214505 506 577 506 56 429 583 538 76 113 466071 098 08 073 095 068 079 071 098 206 0477306 294 347 335 308 295 554 66 71 967 397371 316 34 342 302 359 553 686 801 77 556223 178 181 214 182 215 331 429 525 397 376069 058 063 063 062 065 097 116 145 142 07908 063 065 078 066 07 117 144 176 143 124043 027 03 037 03 035 051 064 085 0559 0556239 175 179 244 183 226 323 407 494 35 333036 027 029 036 03 038 051 063 079 0535 0482

0709653 0709624 0709075 070988 07097 071655 0774180512354 0512398 0512379 051386 05123 051218 0512271891615 18840 18876 18942 18891 18604 19281157253 15685 15716 15721 15692 15703 1573391255 38952 39026 3907 38962 3967 39098

































































10 Conclusions













Acknowledgement


References


































































































































































































































10 Conclusions













Acknowledgement


References













































































































































































Acknowledgement


References





































































































































































Source contamination and tectonomagmatic signals of overlapping Early to Middle Miocene orogenic...

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