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Quaternary Science Reviews 39 (2012) 106e114

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Quaternary Science Reviews

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Expression of the Younger Dryas cold event in the Carpathian Mountains,Ukraine?

V. Rinterknecht a,*, A. Matoshko b, Y. Gorokhovich c, D. Fabel d, S. Xu e

a School of Geography and Geosciences, University of St Andrews, St Andrews, Fife, UKb Institute of Geography, National Academy of Sciences of Ukraine, UkrainecDepartment of Environmental, Geographical and Geological Sciences, Lehman College, City University of New York, USAdDepartment of Geographical and Earth Sciences, University of Glasgow, UKe Scottish Universities Environmental Research Centre, UK

a r t i c l e i n f o

Article history:Received 12 October 2011Received in revised form6 February 2012Accepted 8 February 2012Available online 23 March 2012

Keywords:Surface exposure datingYounger DryasCarpathian Mountains

* Corresponding author. þ44 (0) 1334462382.E-mail address: vr10@st-andrews.ac.uk (V. Rinterk

0277-3791/$ e see front matter Crown Copyright � 2doi:10.1016/j.quascirev.2012.02.005

a b s t r a c t

Past glacial activity in the Ukrainian Carpathian Mountains is characterized by cirques, glacial valleys andmoraine ridges at altitudes between 1350 and 1850 m a.s.l. Although the geomorphology of this area wasextensively studied, the deposition time of these glacial forms, and specifically the moraines was neverdetermined. We surveyed and mapped the geomorphology of the Pozhezhevs’ka glacial Valley, which ispart of the Charnogora Ridge. We used surface exposure dating and developed a data base of this areausing remote sensing and Geographic Information System to understand the timing and nature of glacialevent in the eastern Carpathian Mountains. Well-developed continuous lateral-frontal moraines crossthe valley floor at w1400 m a.s.l. Ten sandstone boulders were sampled from one of these to determinethe deposition time of the moraine. Samples were prepared at the Glasgow University CosmogenicNuclide Laboratory and analyzed at the SUERC AMS Laboratory. Surface exposure ages were calculatedusing the CRONUS-Earth online 10Be exposure age calculator. Our exposure ages for nine samples (UKR-2to UKR-10) range from 11.0 � 0.4 10Be ka to 14.5 � 0.5 10Be ka. One sample (UKR-1) produced no currentand thus no exposure age is available. The mean deposition time for the moraine ranges from 12.4 � 0.3to 12.9 � 0.3 10Be ka, depending on choice of surface erosion and snow cover. These results provide thefirst direct indication, using surface exposure dating, of a possible glacier response in the UkrainianCarpathian Mountains to a cold event contemporary with the Younger Dryas (YD). Together withexposure ages from other mountain ranges across Europe, the new data provide direct chronologicalevidence for a widespread expression of the YD cold event outside the main ice margin limits left by theformer Scandinavian Ice Sheet.

Crown Copyright � 2012 Published by Elsevier Ltd. All rights reserved.

1. Introduction

Great continental ice sheets during the Pleistocene wereaccompanied by remarkable climatic changes in Europe. Theclimatic impact on the nearest proglacial regions is obvious whilefurther away from ice sheet limits palaeoclimatic interpretationsand correlations become more and more equivocal. Among thedifferent geological indicators of glacial to periglacial climaticconditions are remnants of psychrophilic organisms, cryogenicstructures, or loess deposits. South and east of the Scandinavian IceSheet, satellite ice caps developed throughout most Europeanmountains (Ehlers and Gibbard, 2004; Ehlers et al., 2011). These ice

necht).

012 Published by Elsevier Ltd. All

caps left direct imprints of past glacial activity of which well-developed moraines are the most conspicuous. The position andtiming of ancient snow lines in these mountains could play animportant role in reconstructing the glacial climate in zonesoutside the direct influence of the continental ice sheet. Thisreconstruction requires two conditions: 1) the presence of reliablegeomorphological imprints of glaciations, and 2) an estimate oftheir age. The first condition has been widely observed and recor-ded in Europe but glacial chronologies are only starting to beavailable for several areas (see references in Ehlers et al., 2011).While glacial chronologies exist for the mountains of central andsouthern Europe, limited chronologies consisting mostly of radio-carbon dates are available for the Carpathians and CaucasusMountains.

Here we present a study on the glacial geomorphology ofa mountain valley and the direct timing of a prominent moraine in

rights reserved.

Fig. 2. Glaciomorphologic map of the upper north-eastern macroslope of the Char-nogora Ridge, Pozhezhevs’ka Valley (hypsometrical and hydrological features based onthe topographic map of 1:25 000 scale, main contour lines drawn through 100 m,secondary lines - through 20 m) 1e3 e geomorphologic boundaries: 1 e upper limit ofthe glacial cirque, 2 e upper limit of the glacial valley established, 3 e upper limit ofthe glacial valley inferred; 4 e cirque bottom; 5 e back-moraine basin; 6 e moraineridges; 7 e remains of moraines; 8 e sampling points; 9 e position of the geo-morphologic cross-section; 10 e weather-station; 11 e position of the core withradiocarbon dating (Tretyak and Kuleshko, 1982). Capital letters e names of cirques: Ae Arendazh, B e Brescul, Z e Zarosliak. Numbers on the moraines correspond to: 1,3 e

lateral moraines, 2 e frontal moraine; 4 e drawn according to description of Kravchuk(2008); 5e6 e inferred moraines. Dashed line AeB denote the position of the longi-tudinal cross-section (Fig. 3).

V. Rinterknecht et al. / Quaternary Science Reviews 39 (2012) 106e114 107

the eastern Carpathians with prominent footprints of the Pleisto-cene glaciers. Based on our geomorphological survey of themoraine and the large boulders present on the crest of the moraine,The Pozhezhevs’ka Valley (Fig. 1) in the Charnogora Ridge (Ukraine,Ivano-Frankivs’k Oblast) was selected for surface exposure dating(SED) using cosmogenic 10Be.

2. Charnogora-Svydovets’ glaciation

Initial observations of relic landforms of past glaciations withinthe Charnogora Ridge were made by K. Paul’, E. Titce, R. L. Jack and J.Horn at the end of the 19th century (Kravchuk, 2008). Further workwas conducted by Romer (1906), Sviderski (1938), Ivanov (1950),Tsys’ (1961), Tykhanych (1967), and Voropai and Kunytsia (1969).The results of these studies indicated the existence of ancient cirqueand cirque-valley glaciers within the Charnogora, Svydovets’, Chyv-chynyandGorganyRidgesand theRakhivs’kyiMassif in theUkrainianCarpathian Mountains (part of the eastern Carpathians) (Matoshko,2011). These ridges and massifs as well as the rest of the CarpathianMountains are currently glacier free. More thorough field and hyp-sometrical investigation showed that direct glacial imprints arelimited to theCharnogora andSvydovets’Ridges (Fig. 2), aswell as theSyvuliaMassif (Matoshko, 2011). In other places possible evidence forpast active glaciers could be only found on the ridges and peakshigher than 1650e1700 m a.s.l. (modern elevation without ice).

Recent morphological data about the Charnogora and Svydo-vets’ glacial landforms (Kravchuk, 2008) show that classic glacialvalleys are present below the high mountain ridges and peaks. Themost reliably established glacial valleys occur within the elevationrange of 1350e1850 m a.s.l. According to Sviderski (1938) theywere also observed below this range in the upper reaches of thePrut valley (Charnogora) where end moraines in some Svydovets’valleys are found at 1175e1250 m a.s.l. (Kravchuk, 2008). Thevalleys in the region consist of glacial cirques and glacial valleysusually separated by a rock step.

Thecirquesarevariationsof theclassical semi-ring shape resultingin the characteristic scalloped-ridge pattern (Fig. 2). The height of thecirque steep back wall ranges from 130 to 180m. The concave cirquefloors are filled in some places by small lakes or peat bogs.

The typical cirque threshold is not expressed everywhere.Sometimes the lower valley has steep slopes (up to 30�e40�) andnarrow (several tens of meters) proximal part with drops of 80 m.In other cases, only a shallow slope exists between the cirque floorand the valley thalweg. Below the thresholds, the valleys becomewider (up to 400e600m) with a much gentler slope. In some cases,when the valley is traversed by frontal moraines, infill of debris andpeat deposition behind the moraines forms a back-moraine basinresulting in a flatter valley floor. Well-preserved ridges of lateral,

Fig. 1. Location map of the

and end moraines (relative height: 3e12 m, length �400 m) arerare in these valleys and form less than two-third of the morainecomplexes. The distal sections of the glacial valleys are character-ized by increased slope steepness with remains of washed outmoraines on the slopes. According to Kravchuk (2008), most glacialvalleys are 1.5e2.0 km long with rare cases reaching 5.0e6.0 km.

Immediately down-valley of the glacial influence, fluvialgeomorphology dominates the landscape (Fig. 3) with the highestelevation river terraces located atw1130 m a.s.l. (Matoshko, 2004).

Glacial deposits are represented by moraines composed ofsandy-clay matrix supporting sub-rounded boulders (�5 m3).Relict glacial landforms are severely modified, or completely

Pozhezhevs’ka Valley.

Cirque Glacial valleymeters a.s.l.

1800

1700

1600

1500

1400

1300

Rid

gesa

ddle

back

wal

l

botto

m

rock

-ste

p

back

-mor

aine

bas

in

fron

tal m

orai

ne r

idge

end

of s

tudi

ed g

laci

al v

alle

y

Riv

er v

alle

y

A B

Fig. 3. Longitudinal cross-section through the Pozhezhevs’ka Valley (see Fig. 2).

V. Rinterknecht et al. / Quaternary Science Reviews 39 (2012) 106e114108

destroyed by intensive postglacial processes such as weathering,fluvial erosion, nivation, and deposition of scree at the base of theslopes, and biogenic deposits on the cirques’ floor and beyond theend moraines.

3. Pozhezhevs’ka valley and the sampling site

The Pozhezhevs’ka Valley is situated east of the CharnogoraRidge, a ridge between the Brescul cirque and Pozhezhevs’kasummits: 1911 and 1822 m a.s.l. respectively (Fig. 2). The typicalsuccession of glacial valley landforms consists of a steep head wall,an over-deepened basin, a rock step, and moraines, all of whichwere identified and mapped in the Pozhezhevs’ka Valley (Figs. 3and 4). Clear moraine ridges between 5 and 10 m high whereformed by former glacial activity below the rock step and providethe best evidence of the former extent of glaciers in the valley(Fig. 5).

The lithology of the upper part of the Charnogora Nappe iscomposed of the uniform Upper Cretaceous sandstones of theCharnogora Suite. The most suitable material for SED analysiscomes from glacially transported boulders, preferentially >1 m inheight above ground, and located at the surface of the lateral andfrontal moraines (Figs. 1 and 2). Such boulders are rare becausemoraines are composed principally of small or barely emergingboulders and cobbles. It should be noted that the moraine ridgesare clearly separated from the rest of the valley slopes, both froma geomorphological and compositional point of view. Most of thevalley slopes are covered by vegetation that increases the slopestability. In other areas, bare of vegetation, modern screes displayfresh accumulation of angular and unsorted material eroded fromthe steep walls of the glacial cirque. Such screes are widespread on

Fig. 4. Pozhezhevs’ka Valley view from the rock step: 1 e rock step, 2 e back-moraine

the northwestern side of the glacial valley but the debris accumu-lations do not reach the moraines located closer to the center of thevalley. The glacial diamicton forming the core material of themoraines is characterized by a heterogeneous size material rangingfrom clay to boulders several meters in diameter. Both themorainesposition within the valley and their composition make them easilydistinguishable from the scree accumulation. In addition, thepresence of undisturbed mature forest growing on top of themoraine and in the depression between the moraine and the screeareas indicate landform stability giving us confidence in the choiceof the sites for surface exposure dating. Based on these observa-tions we identified glacially transported boulders resting on thecrest of the lateral and frontal moraines for sampling and avoidedquestionable areas where moraine and stabilized screes could havemerged in the past.

4. Methods

4.1. Boulder collections

We collected 10 samples in the Pozhezhevs’ka Valley ona continuous moraine (Figs. 1 and 2, Table 1). We sampled thelargest boulders available at the surface of the moraine, repre-senting the best stable erratics available for surface exposure dating(Fig. 5). The boulder heights range from 0.6 m to 2.1 m, with anaverage of 1.4 m, and the volume above ground varies between3.6 m3 and 23.3 m3. We systematically sampled the top flat surfacewith a manual jackhammer assuming that the boulder top wasexposed to secondary cosmic rays since deposition of the boulder atthe ice margin. All boulders are composed of Upper Cretaceoussandstones of the Charnogora Suite, with a quartz content rangingbetween 5% and 20%. Quartz is the primary mineral for surfaceexposure dating using cosmogenic 10Be.

4.2. Sample preparation and analysis

All samples were crushed and sieved in order to isolate the250e500 mm fraction. Quartz separation and purification wascarried out at the School of Geographical and Earth Sciences,University of Glasgow, using magnetic separation and mineralfloatation techniques prior to chemical etching procedures modi-fied from Kohl and Nishiizumi (1992). Quartz purity was assayedusing Flame-AAS. Beryllium extraction was carried out in theGlasgow University Cosmogenic Isotope Laboratory housed at theScottish Universities Environmental Research Centre (SUERC) inEast Kilbride, using methods modified from Child et al. (2000).Beryllium isotope ratios in the samples and one procedural blanks

basin, 3 e sampled frontal moraine, 4 e fluvial valley merging with the Prut River.

Fig. 5. Sample UKR-6 showing the position of the boulder on top of the moraine crest.

V. Rinterknecht et al. / Quaternary Science Reviews 39 (2012) 106e114 109

weremeasured at the SUERC Accelerator Mass Spectrometry (AMS)Laboratory. The procedural blank contained <3% of the total atomsin the samples, except for samples UKR-4 (w6%). Data were nor-malised directly against the National Institute of Standards andTechnology (NIST) standard reference material 4325 witha nominal isotope ratio of 3.06�10�11 rather than the NISTcertifiedvalue.

4.3. Surface exposure age calculation

Converting 10Be concentrations to exposure ages requires theuse of an effective 10Be production rate. We adopt here a modern10Be spallation production rate at sea level and high-latitude of4.5 � 0.4 atoms g�1 yr�1, computed for internal consistency fromthe data of Stone (2000) according to the conclusions of therecently published study on absolute calibration of 10Be AMSstandards by Nishiizumi et al. (2007).

The production rates of cosmogenically produced isotopes suchas 10Be are affected by the altitude, latitude and the variation of thegeomagnetic field. The CRONUS-Earth online 10Be exposure agecalculator version 2.2 (http://hess.ess.washington.edu/math/)provides a convenient means for calculating surface exposure agesusing four different scaling schemes (Lm, De, Du, and Li) summa-rizing the main attempts to correct for these effects (Balco et al.,2008). We report here the exposure ages calculated with the“Lm” and the “Du” scaling schemes (Table 2). The “Lm” method

Table 1Sample characteristics.

Sample ID Long E (DD) Lat N (DD) Elevation (m a.s.l.) Thi

UKR-1 24.5284 48.1577 1390 5.1UKR-2 24.5294 48.1581 1383 5.1UKR-3 24.5298 48.1581 1385 2.3UKR-4 24.5306 48.1583 1379 4.2UKR-5 24.5312 48.1570 1383 3.5UKR-6 24.5283 48.1535 1424 2.6UKR-7 24.5294 48.1540 1422 3.9UKR-8 24.5310 48.1551 1398 2.8UKR-9 24.5315 48.1555 1392 3.9UKR-10 24.5321 48.1561 1385 3.1

provides the closest fit to existing calibration data and uses thescaling factors proposed by Lal (1991) and Stone (2000), and isfurther accommodated for paleomagnetic corrections following thedescription of Nishiizumi et al. (1989). As such, we think that theexposure ages calculated with this scaling method (Lm) representthe best age estimates of the exposure of the samples and we usethese exposure ages in the result and discussion sections. The “Du”method is mainly a function of cutoff rigidity and atmosphericpressure (Dunai, 2001) and provides the oldest exposure ages. The“Li” method proposed by Lifton et al. (2005) produces exposureages slightly older than the “Lm” method and the “De” methodproposed by Desilets et al. (2006) produces exposure ages slightlyyounger than those calculated with the “Du” method.

We correct the production rate for sample thickness using anexponential function (Lal, 1991), and assuming a density of2.3 g cm�3 for sandstone. The production rates could be furtheraffected by intermittent snow cover, vegetation cover, and erosionrate. We apply a conservative snow depth of 50 cm for five monthsper year with a snow density of 0.3 g cm�3 Cerling and Craig (1994)calculated the effect of vegetation cover (old growth Douglas firforest) on the production rate of 3He and concluded that thecorrection is minor (about 4% reduction of the 3He production rate).Similarly, simulation with three-dimensional old growth forestsshows a 2.3%e7.3% shielding effect on cosmic radiation (Plug et al.,2007). Our sampling area is covered by young spruce tree forest andwe infer that differences in mean biomass and moisture content

ckness (cm) Shielding correction Quartz (g) Be carrier (mg)

0.99 22.1740 0.22400.99 22.7770 0.22400.99 26.2110 0.22400.99 8.7720 0.22380.99 25.0530 0.22380.99 21.1160 0.22430.99 20.4700 0.22380.99 20.5140 0.22320.99 26.8620 0.22370.99 24.8980 0.2239

Table 210Be concentration and calculated surface exposure ages.

Sample ID [10Be] (104 at g�1)a Lm scaling ages (10Be ka)b Du scaling ages (10Be ka)b

ε ¼ 0 mm ka�1 no snow ε ¼ 2.0 mm ka�1 snow cover ε ¼ 0 mm ka�1 no snow ε ¼ 2.0 mm ka�1 snow cover

Moraine agec 12.4 ± 0.3 12.9 ± 0.3 13.0 ± 0.3 13.5 ± 0.3UKR-1 Low current e e e e

UKR-2 21.849 � 0.682 14.0 � 0.4 14.5 � 0.5 14.6 � 0.5 15.2 � 0.5UKR-3 17.515 � 0.623 11.0 � 0.4 11.4 � 0.4 11.5 � 0.4 11.9 � 0.4UKR-4 19.429 � 0.746 12.4 � 0.5 12.9 � 0.5 13.0 � 0.5 13.5 � 0.5UKR-5 19.566 � 0.579 12.4 � 0.4 12.9 � 0.4 13.0 � 0.4 13.5 � 0.4UKR-6 19.603 � 0.604 11.9 � 0.4 12.4 � 0.4 12.5 � 0.4 13.0 � 0.4UKR-7 20.224 � 0.823 12.5 � 0.5 12.9 � 0.5 13.0 � 0.5 13.5 � 0.6UKR-8 19.052 � 0.632 11.9 � 0.4 12.3 � 0.4 12.4 � 0.4 12.9 � 0.4UKR-9 21.702 � 0.687 13.7 � 0.4 14.2 � 0.5 14.3 � 0.5 14.9 � 0.5UKR-10 19.561 � 0.660 12.3 � 0.4 12.8 � 0.4 12.9 � 0.4 13.4 � 0.5

a All samples measured at the SUERC AMS Laboratory.b All ages calculated using the CRONUS-Earth online 10Be exposure age calculator version 2.2 (http://hess.ess.washington.edu/math/), (Balco et al., 2008) with a time-

dependent production rate model and according to the Lal (1991) and Stone (2000) scaling scheme (Lm) and the Dunai (2001) scaling scheme (Du). Analytical uncer-tainties for single exposure ages (reported as 1 sigma) include a 2% uncertainty associated with the chemical processing, analytical blank correction and AMS measurementuncertainty on single measurement. A rock density of 2.3 g cm�3 was used for the sandstone samples. The procedural blank is 11.3 � 1.7 � 104 10Be atoms which is typicallybetween 2 and 3% of the number of 10Be atoms in the samples.

c Mean moraine age. The �1s uncertainty corresponds to the standard deviation of the mean exposure ages.

V. Rinterknecht et al. / Quaternary Science Reviews 39 (2012) 106e114110

between tree species would result in an even smaller correction ofthe relative production rate and therefore we do not correct for thevegetation cover effect. We apply an erosion rate of 2.0 mm ka�1 onour sandstone samples. The 2.0 mm ka�1 erosion rate is an estimateused to illustrate the possible effect of erosional processes on theexposure ages. A doubling of this estimate would increase theexposure age of a boulder exposed for 12.4 ka by<2% (w200 years).

Fig. 6. Exposure ages and probability plots for nine samples from the Pozhezhevs’ka Valley.and calculated using the Lm scaling method. Open diamonds correspond to exposure ages cbars for single 10Be exposure ages correspond to 1 sigma analytical uncertainty only. The dmoraine age (solid black line). The light smooth shaded grey band includes the uncertainshaded grey band corresponds to the analytical uncertainties for the mean moraine age (dproduction rate in addition to the analytical uncertainties.

Corrected and uncorrected exposure ages for the estimated snowcover and erosion rate are reported in Table 2.

Finally, surface production rates were also corrected for topo-graphic shielding due to surrounding topography using the onlinetopographic shielding calculator available at: http://hess.ess.washington.edu/math/. Analytical uncertainties (reported as 1sigma) include the uncertainty associated with the chemical and

Black diamonds correspond to exposure ages not corrected for snow cover nor erosionorrected for snow cover and erosion and calculated using the Du scaling method. Errorark smooth shaded grey band corresponds to the analytical uncertainty for the meanty on the production rate in addition to the analytical uncertainties. The dark stripedashed black line). The light striped shaded grey band includes the uncertainty on the

Table 3Radiocarbon ages for the Pozhezhevs’ka Valley.

Sample # Depth (cm) Carbonsource

d13C 14C age (yrs)a Calibrated age(cal yr BP)b

Ku-1075 13e20 Peat N/A 1180 � 30 1100 � 40Ku-1088 40e52 Peat N/A 2340 � 50 2380 � 70

a Tretyak and Kuleshko (1982).b Calibration of the radiocarbon ages was performed using the programme

CALIB 6.0 (Stuiver et al., 2005) and the calibration curve INTCAL09 (Reimer et al.,2009).

V. Rinterknecht et al. / Quaternary Science Reviews 39 (2012) 106e114 111

analytical blank correction (the associated 10Be/9Be blank ratio was7.2 � 1.1 �10�15), as well as the AMS measurement uncertainty foreach individual sample measurement.

5. Results

The close proximity of the samples and their position on a singlemoraine ridge strongly suggest that their exposure history is thesame. One sample, UKR-1, produced very low current and couldtherefore not be measured. Taking only the analytical uncertaintiesinto account, the nine remaining samples’ (UKR-2 to UKR-10)exposure ages range from 11.0 � 0.4 10Be ka (no correction) to14.5 � 0.5 10Be ka (corrected for snow cover and erosion). AShapiroeWilk test indicates that we cannot reject the normalityassumption for the sample population distribution (W ¼ 0.91, p-value ¼ 0.34). Because the observed variability (7.3%) is more thanthe analytical uncertainty (3.4%), this suggests that the randomuncertainties are dominated by geological uncertainties rather thananalytical ones. In the absence of obvious geological uncertainties,except the possible one linked to erosion, we calculate a meanexposure age for the nine samples between 12.4 � 0.3 (no erosionand no snow cover) and 12.9 � 0.3 10Be ka (taking into accounterosion and snow cover) (Fig. 6). The uncertainty corresponds tothe standard deviation of the mean exposure ages (Table 2). Thisresult suggests that the moraine was deposited during the earlystage of the YD.

6. Discussion

6.1. Regional implication

The glacial history of the Ukraine was heavily influenced bythe repeated incursions of the Eurasian ice sheet in the north-east and northwest part of the country. Evidence for theseincursions were found mainly for the Oka Glaciation (Ukrainianequivalent of the South Polish, Elsterian, or Mindel Glaciation,w500 to 460 ka ago), and the Dnieper Glaciation (Ukrainianequivalent of the Middle Polish, Saalian, or Riss Glaciation,w420 to 130 ka ago) in Ukraine (Matoshko, 2004, 2011;Velichko et al., 2004).

Mountain glaciation was constrained to high grounds in theUkrainian Carpathian. Romer (1906) was the first to observegeomorphological evidence for two former glaciations in the Svy-dovets’ which were subsequently developed in two glacialcomplexes by Sviderski (1938). The first, less extensive and older,complex was associated with the Oka Glaciation. The second, moreextensive and younger, complex was associated with the DnieperGlaciation. It is only in the early 60’s that Tsys’ (1961) hypothesisedthe possibility of the expression of two cold events during Wür-mian Glaciation in the Carpathian Mountains. The WürmianGlaciation has no equivalent in the Ukrainian stratigraphy as theglacial extent was restricted to the mountain area and left the lowgrounds of the Dnieper unaffected by ice at that time.

Urdea (2004) carried out geomorphological analysis on glaciallandforms in the Romanian Carpathians. According to his data thePleistocene glaciers left numerous anddiverse traces of their activityamong which cirques, glacial valleys, erratics, roches moutonnées,striations, lateral and frontal moraines. These glacial features wereassociated with the Rissian and Würmian Glaciations based on therelative correlation betweenmoraines and fluvial terraces as well aspollen analysis (Urdea, 2004). The closest site investigated by Urdea(2004) is the Rodna Mountains, <100 km south from our study site,and belongs to the Southern Carpathians. Within these mountains,valleys with a north-northeast orientation, similar to the Pozhez-hevs’ka Valley orientation in Ukraine, were filled by the former

Bistricioara-Putredu and Repedea-Buh�aiescu glaciers. The glaciersreached an elevation of 848e1100m a.s.l. andwere as long as 17 kmduring theRissianGlaciation. During theWürmian, the glacier frontsreached an elevation of 1190 m a.s.l. and again based on the relativetiming, the YD moraine was deposited at an elevation of w1930ma.s.l. (Urdea, 2004). This isw500mhigher than theYDmorainewedated in Ukraine. Although, a clear glacial sequence has been iden-tified on geomorphological evidence in the Southern Carpathians,the relative timing cannot be used as a robust glacial chronology.

Radiocarbon ages (Tretyak and Kuleshko, 1982) (Table 3) wereobtained in the Pozhezhevs’ka Valley from within the back-moraine basin (Fig. 2). The two calibrated ages: 1100 � 40 and2380 � 70 cal year BP, give Holocene ages for the formation of twodistinct peat layers separated by w20 cm of silt and sand. The peatlayers overlay a basal moraine or till layer in the sediment core andthe oldest calibrated ages therefore represent a minimum age forthe deposition of the moraine we dated. Because the core stops inthe till layer, there is no time constraint from below the till and it isnot possible to correlate the till with the moraine we dated. Giventhe young peat age we suspect that the till is related to a possiblyyounger cold event, less extensive than the YD cold event asexpressed in the valley. Alternatively, the conditions for peataccumulation could have been reached only during the late Holo-cene at this site or regionally at this altitude.

6.2. Continental implication

The YD cold event was first identified as a stratotype in Scan-dinavia (Mangerud et al., 1974). The deposition time of the contin-uous moraine belts (three prominent ridges) in Fennoscandinaviaand in Russian Karelia was determined indirectly by a combinationof radiocarbon ages, varve chronologies, and palaeomagneticstudies (Andersen et al., 1995; Saarnisto and Saarinen, 2001). Theuse of surface exposure dating established the deposition age of themost conspicuous ridge in Finland (the Salpausselkä I Moraine):12.5 � 0.7 10Be ka (Tschudi et al., 2000; Rinterknecht et al., 2004),thus constraining temporarily an important step in the retreatsequence of the Scandinavian Ice Sheet.

The occurrence of a Lateglacial cold event has been recognizedin many formerly glaciated regions in Europe and in the rest of theworld including the southern hemisphere and the timing of itsexpression is at the center of an ongoing debate revolving aroundclimatic lead and lag between the northern and southern hemi-sphere (Ackert et al., 2008; Kaplan et al., 2010). At stake, ourunderstanding of the mechanism for the abrupt interruption of thelast deglaciation process between w12.9 and w11.7 ka ago(Rasmussen et al., 2006; Brauer et al., 2008) before the start of theHolocene. While various dating techniques with inherent accura-cies and precisions were used to define the YD time frame, theseapproaches may to some extent have provided the fuel igniting thedebate on the synchrony or asynchrony of events globally.

The use of a single dating technique, such as surface exposuredating, to compare the timing of glacier fluctuations in both thenorthern and southern hemispheres was attempted by Ivy-Ochs

Table 4Summary of the 10Be surface exposure ages in Europeanmountain ranges during theYounger Dryas and excluding the Scandinavian Ice Sheet.

Region/country Sample ID Lm scaling ages (10Be ka)a

ε ¼ 0 mm ka�1

no snowε ¼ 1.0 mm ka�1

snow cover

Pyreneesf

Mulleres moraine MUL01 11.4 � 2.0 11.8 � 2.0MUL04 11.5 � 1.3 11.8 � 1.4

11.5 ± 1.1b 11.8 ± 1.1b

Outer Pleta Naua moraine OPN01 11.6 � 1.2 12.0 � 1.2OPN02 11.1 � 1.5 11.4 � 1.6OPN03 11.0 � 1.1 11.4 � 1.2

11.3 ± 0.7b 11.6 ± 0.7b

Llastres de Bessiberri moraine LDB01 11.0 � 1.1 11.2 � 1.1LDB02 11.1 � 1.6 11.5 � 1.0LDB03 11.1 � 1.1 11.4 � 1.1

11.0 ± 0.7b 11.4 ± 0.6b

AlpsGrosser Aletschg AG-1 10.9 � 0.5 11.3 � 0.5

AG-2 10.3 � 0.7 10.6 � 0.8AG-4c 11.3 � 0.4 11.7 � 0.4AG-5 10.5 � 0.8 10.8 � 0.8

11.1 ± 0.3b 11.4 ± 0.3b

Val Violah VVm4 10.7 � 0.6 11.0 � 0.7VVm5 11.3 � 0.3 11.6 � 0.3

11.2 ± 0.3b 11.5 ± 0.3b

Piano del Prajeti PDP-1 12.2 � 05 12.6 � 0.5PDP-2 12.0 � 0.7 12.3 � 0.7PDP-3 11.4 � 0.5 11.8 � 0.5PDP-4 10.6 � 0.5 10.9 � 0.5

11.9 ± 0.2d 12.2 ± 0.2d

Schönferwallj F1 11.8 � 0.8 12.2 � 0.9F2 12.3 � 0.8 12.7 � 0.9F3 11.5 � 0.5 11.8 � 0.6F4b 11.8 � 0.6 12.2 � 0.6

11.9 ± 0.2d 12.3 ± 0.2d

Julier Passj

Outer ridge J12 13.4 � 1.2 13.8 � 1.2J14 10.8 � 0.5 11.1 � 0.5J18 12.9 � 0.8 13.3 � 0.8J200 11.2 � 0.5 11.6 � 0.5

12.4 ± 0.7d 12.8 ± 0.7d

Inner ridge J8 11.4 � 0.6 11.7 � 0.6J10 11.1 � 0.7 11.4 � 0.7J104 11.6 � 0.6 11.9 � 0.6

11.4 ± 0.3b 11.7 ± 0.4b

TurkeySki (Uluda�g Mountain)k TRU-10 11.4 � 0.5 11.7 � 0.5

TRU-11 12.2 � 0.4 12.6 � 0.4TRU-13 12.4 � 0.6 12.8 � 0.6

12.0 ± 0.3b 12.4 ± 0.3b

Retezat TRK-23 11.2 � 0.7 11.5 � 0.7(Kaçkar Mountains)l TRK-24 12.6 � 0.6 13.0 � 0.6

11.9 ± 0.7d 12.3 ± 0.7d

Carpathian Mountains RomaniaPietrele PT-03-02e 10.8 � 0.4 11.1 � 0.4(Retezat Mountains)m PT-03-03e 12.9 � 0.5 13.3 � 0.5UkrainePozhezhevs’ka Valleyn 12.4 ± 0.3d 12.9 ± 0.3d

a All ages calculated using the CRONUS-Earth online 10Be exposure age calculatorversion 2.2 (http://hess.ess.washington.edu/math/)(Balco et al., 2008) with a time-dependent production rate model and according to the Lal (1991) and Stone(2000) scaling scheme (Lm). Analytical uncertainties for single exposure ages(reported as 1 sigma) include the AMS measurement uncertainty only. A rockdensity of 2.3 g cm�3 was used for the sandstone samples.

b Error-weighted mean moraine age. The �1s uncertainty corresponds to theerror-weighted mean of the analytical uncertainty.

c Error-weighted mean of two exposure ages from a single quartz vein materialsplit in two samples.

V. Rinterknecht et al. / Quaternary Science Reviews 39 (2012) 106e114112

et al. (1999) and was subsequently developed by Barrows et al.(2007) and Kaplan et al. (2010, 2011). This approach drasticallyreduces the uncertainties to the sole internal uncertainties per-taining to the specific dating approach. Based on 10Be ages, theLateglacial cold event as expressed in New Zealand and Patagonia,is now thought to have been influenced by a southerly climaticsignature (Kaplan et al., 2010). This clearly differentiates it from itsnortherly counterpart, the YD, which was triggered by the climateprevailing in the North Atlantic region (Brauer et al., 2008).

In Europe, the YD is probably the most extensively studiedcold event and a significant data set of 10Be ages, out with theages obtain for the Salpausselkä I Moraine in Finland, can now becompiled from the main high mountainous regions across thecontinent: the Alps, the Pyrenees, the Uluda�g and KaçkarMountains in Turkey, and the Carpathian Mountains (Table 4).The available exposure ages were recalculated using the CRONUS-Earth online 10Be exposure age calculator version 2.2 andapplying the same corrections to all samples (e.g. snow cover,erosion) to allow direct comparison of the results. Individualexposure ages range between 13.8 � 1.2 10Be ka and10.6 � 0.8 10Be ka across all the mountain ranges. Two boulderssampled inside and outside a prominent moraine in the RetezatMountains (Romania): 13.3 � 0.5 10Be ka and 11.1 � 0.4 10Be kabracket the deposition time of the moraine, contemporaneous ofthe YD, rather than directly date it (Reuther et al., 2007). Thedistribution of the moraine ages across Europe is tighter than theindividual exposure ages distribution and varies between12.9 � 0.3 10Be ka (in the Carpathians Mountains) and11.4 � 0.6 10Be ka (in the Pyrenees), reflecting moraine depositionduring the full time range of the YD event (w12.9ew11.7 ka). Thissuggests that valley glaciers responded to palaeoclimaticconditions that: 1. prevailed during times of major atmosphericreorganization (Brauer et al., 2008), and 2. were influenced bythe geographical location of the mountain ranges across Europe(Kuhlemann et al., 2009; Tóth et al., 2012).

The Julier’s Pass in the Alps, is the only site where two distinctmoraines, the inner and outer moraines contemporaneous of theYD have been directly dated (Table 4). In other valleys in the Alpstwo ridges have been mapped but only one of the moraines wasdated. For example in Piano del Prajet and Schönferwall an earlyretreat was recorded, and in Val Viola a late retreat was recorded.In the case of the Grosser Aletsch, a single lateral moraine wasdated at 11.4 � 0.3 10Be ka suggesting that the glacier respondedlate to climate forcing.

In otherhighmountain ranges YDevents havebeen recorded andan east-west pattern can be distinguished. The moraine depositiontime shows a clear east towest youngingwith an early retreat in theeastern mountain ranges (Uluda�g, Kaçkar, and Carpathians) from12.9� 0.3 to 12.3� 0.7 10Be ka (this paper, Akçar et al., 2007; Zahnoet al., 2010), and a late retreat in the Pyrenees from 11.8 � 1.1 to11.4�0.6 10Beka (Pallàs et al., 2006). This pattern couldhighlight the

d Mean moraine age. The �1s uncertainty corresponds to the standard deviationof the mean exposure ages.

e Single boulder inside and outside a distinct moraine ridge. The two exposureages possibly bracket the deposition time of the moraine ridge itself (Reuther et al.,2007).

f Pallàs et al., 2006.g Kelly et al., 2004.h Hormes et al., 2008.i Federici et al., 2008.j Ivy-Ochs et al., 2009.k Zahno et al., 2010.l Akçar et al., 2007.

m Reuther et al., 2007.n This study.

V. Rinterknecht et al. / Quaternary Science Reviews 39 (2012) 106e114 113

strengthand regional imprints of themechanismsat theoriginof theYD cool event: e.g. changes in themeridional overturning circulation(McManus et al., 2004) accompanied by increased wind strength(Brauer et al., 2008). The initial strong abrupt climate shift wouldhave reached deep into the continent, triggering a strong positive/growth response from glaciers in the Alps (outer moraines) andfurther east, but leaving the Pyrenees in a region of increased aridityas suggested by combined marine and terrestrial records of thewestern Mediterranean (Combourieu Nebout et al., 2002). As theclimate shift lost momentum towards the end of the YD, climaticconditions progressively returned to milder andmoister conditions,allowing glaciers to stagnate in the Alps (inner moraines) and in thePyrenees.

7. Conclusions

The results of the present study are an important primary step inthe precise age determination of the chronology of the EasternCarpathians glaciation (glaciations). The moraine age of 12.9 � 0.310Be ka (n¼ 9) firmly indicates the presence of active valley glacierson Charnogora Ridge at the onset of the YD cool event. The pres-ence of prominent glacial features (moraines) outside the datedmoraine, suggest that older glacial episodes (Last Glacial Maximumor older) have been recorded in the landscape and requires furtherinvestigation.

The expression of the YD in the Carpathians Mountainscontributes to the growing data set of direct surface exposuredating using 10Be. The use of a common dating technique allows fordirect comparison of the growth and decay of alpine type glaciersacross Europe. While the dating resolution is not fine enough tomake inferences about climate mechanisms directly, it is never-theless possible to highlight general trends in glacier dynamicsresponding to climate forcing. We observe that shortly after theonset of the YD, due to a strong climatic shift, glaciers retreated inthe Alps and further east but not in the Pyrenees. Towards the endof the YD, glaciers stagnated in the Alps and in the Pyrenees sug-gesting a response to the prevailing improving climatic conditions.

Acknowledgements

We greatly acknowledge the generous help of Professor PiotrGozhik as well as Dr Orest Stelmakh for assistance in organizing thefield investigation. The help and support of M. Miguens-Rodriguezto prepare the samples in the Glasgow University CosmogenicIsotope Laboratory housed at the Scottish Universities Environ-mental Research Centre (SUERC) in East Kilbride is warmlyacknowledged. We thank P. Hughes and an anonymous reviewerfor improving the manuscript. This research was supported by theRoyal Society Research Grants scheme and the Climate Center of theLamont-Doherty Earth Observatory.

References

Ackert, R.P., Becker, R.A., Singer, B.S., Kurz, M.D., Caffee, M.W., Mickelson, D.M., 2008.Patagonian glacier response during the late GlacialeHolocene transition.Science 321, 392e395.

Akçar, N., Yavuz, V., Ivy-Ochs, S., Kubik, P.W., Vardar, M., Schlüchter, C., 2007.Paleoglacial records from Kavron Valley, NE Turkey: field and cosmogenicexposure dating evidence. Quaternary International 164e165, 170e183.

Andersen, B.G., Lundqvist, J., Saarnisto, M., 1995. The younger Dryas margin of theScandinavian ice sheet-an introduction. Quaternary International 28,145e146.

Balco, G., Stone, J.O., Lifton, N.A., Dunai, T.J., 2008. A complete and easily accessiblemeans of calculating surface exposure ages or erosion rates from 10Be and 26Almeasurements. Quaternary Geochronology 3, 174e195.

Barrows, T.T., Lehman, S.J., Fifield, L.K., De Deckker, P., 2007. Absence of cooling inNew Zealand and the Adjacent Ocean during the younger Dryas Chronozone.Science 318, 86e89.

Brauer, A., Haug, G.H., Dulski, P., Sigman, D.M., Negendank, J.F.W., 2008. An abruptwind shift in western Europe at the onset of the Younger Dryas cold period.Nature Geoscience 1, 520e523.

Cerling, T.E., Craig, H., 1994. Cosmogenic 3He production rates from 39�N to 46�Nlatitude, western USA and France. Geochimica et Cosmochimica Acta 58,249e255.

Child, D., Elliott, G., Mifsud, C., Smith, A.M., Fink, D., 2000. Sample processing forearth science studies at ANTARES. Nuclear Instruments and Methods in PhysicsResearch Section B: Beam Interactions with Materials and Atoms 172, 856e860.

Combourieu Nebout, N., Turon, J.L., Zahn, R., Capotondi, L., Londeix, L., Pahnke, K.,2002. Enhanced aridity and atmospheric high-pressure stability over thewestern Mediterranean during the North Atlantic cold events of the past 50 ky.Geology 30, 863e866.

Desilets, D., Zreda, M., Prabu, T., 2006. Extended scaling factors for in situ cosmo-genic nuclides: new measurements at low latitude. Earth and Planetary ScienceLetters 246, 265e276.

Dunai, T.J., 2001. Reply to comment on ‘scaling factors for production rates of in situproduced cosmogenic nuclides: a critical reevaluation’ by Darin Desilets, MarekZreda and Nathaniel Lifton. Earth and Planetary Science Letters 188, 289e298.

Ehlers, J., Gibbard, P., 2004. Quaternary Glaciations - Extent and Chronology: Part I:Europe. Elsevier, Amsterdam.

Ehlers, J., Gibbard, P.L., Hughes, P.D., 2011. Quaternary Glaciations e Extent andChronology. A Closer Look. Elsevier, Amsterdam.

Federici, P.R., Granger, D.E., Pappalardo, M., Ribolini, A., Spagnolo, M., Cyr, A.J., 2008.Exposure age dating and equilibrium line altitude reconstruction of an Egesenmoraine in the Maritime Alps, Italy. Boreas 37, 245e253.

Hormes, A., Ivy-Ochs, S., Kubik, P.W., Ferreli, L., Maria Michetti, A., 2008. 10Beexposure ages of a rock avalanche and a late glacial moraine in Alta Valtellina,Italian Alps. Quaternary International 190, 136e145.

Ivanov, B.N., 1950. Sledy oledeneniya Ukrainskih Carpat. (The Traces of UkrainianCarpathians Glaciation). In: series geol.-geomorpho, vol. 2. Uchenye ZapiskiChernovitskogo Universiteta, 8, pp. 14e21.

Ivy-Ochs, S., Kerschner, H., Maisch, M., Christl, M., Kubik, P.W., Schlüchter, C., 2009.Latest Pleistocene and Holocene glacier variations in the European Alps.Quaternary Science Reviews 28, 2137e2149.

Ivy-Ochs, S., Schlüchter, C., Kubik, P.W., Denton, G.H., 1999. Moraine exposure datesimply synchronous younger Dryas glacier Advances in the European Alps and inthe Southern Alps of the New Zealand. Geografiska Annaler 81, 313e323.

Kaplan, M.R., Schaefer, J.M., Denton, G.H., Barrell, D.J.A., Chinn, T.J.H., Putnam, A.E.,Andersen, B.G., Finkel, R.C., Schwartz, R., Doughty, A.M., 2010. Glacier retreat inNew Zealand during the younger Dryas stadial. Nature 467, 194e197.

Kaplan, M.R., Strelin, J.A., Schaefer, J.M., Denton, G.H., Finkel, R.C., Schwartz, R.,Putnam, A.E., Vandergoes, M.J., Goehring, B.M., Travis, S.G., 2011. In-situcosmogenic 10Be production rate at Lago Argentino, Patagonia: implications forlate-glacial climate chronology. Earth and Planetary Science Letters 309, 21e32.

Kelly, M.A., Kubik, P.W., von Blanckenburg, F., Schluechter, C., 2004. Surface exposuredating of the Great Aletsch Glacier Egesen moraine system, western Swiss Alps,using the cosmogenic nuclide 10Be. Journal of Quaternary Science 19, 431e441.

Kohl, C.P., Nishiizumi, K., 1992. Chemical isolation of quartz for measurement of in-situ -produced cosmogenic nuclides. Geochimica et Cosmochimica Acta 56,3583e3587.

Kravchuk, Y., 2008. Geomorphology of the Polonyna-Chornohora Carpathians Lviv.Publishing center of I. Franko Lviv national University. 188 p.

Kuhlemann, J., Milivojevi�c, M., Krumrei, I., Kubik, P.W., 2009. Last glaciation of the�Sara range (Balkan Peninsula): increasing dryness from the LGM to the Holo-cene. Austrian Journal of Earth Sciences 102, 146e158.

Lal, D., 1991. Cosmic ray labeling of erosion surfaces: in situ nuclide production ratesand erosion models. Earth and Planetary Science Letters 104, 424e439.

Lifton, N.A., Bieber, J.W., Clem, J.M., Duldig, M.L., Evenson, P., Humble, J.E., Pyle, R.,2005. Addressing solar modulation and long-term uncertainties in scalingsecondary cosmic rays for in situ cosmogenic nuclide applications. Earth andPlanetary Science Letters 239, 140e161.

Mangerud, J., Andersen, S.T., Berglund, B.E., Donner, J.J.,1974. Quaternary stratigraphyof Norden, a proposal for terminology and classification. Boreas 3, 109e128.

Matoshko, A.V., 2004. Pleistocene glaciations in Ukraine. In: Ehlers, J., Gibbard, P.(Eds.), Quaternary Glaciations e Extent and Chronology. Part 1: Europe.Elsevier, Amsterdam.

Matoshko, A.V., 2011. Limits of the Pleistocene glaciations in the Ukraine: a closerLook. In: Ehlers, J., Gibbard, P.L., Hughes, P.D. (Eds.), Developments in Quater-nary Science. Elsevier, pp. 405e418.

McManus, J.F., Francois, R., Gherardi, J.M., Keigwin, L.D., Brown-Leger, S., 2004.Collapse and rapid resumption of Atlantic meridional circulation linked todeglacial climate changes. Nature 428, 834e837.

Nishiizumi, K., Imamura, M., Caffee, M.W., Southon, J.R., Finkel, R.C., McAninch, J.,2007. Absolute calibration of 10be AMS standards. Nuclear Instruments andMethods in Physics Research B 258, 403e413.

Nishiizumi, K., Winterer, E.L., Kohl, C.P., Klein, J., Middleton, R., Lal, D., Arnold, J.R.,1989. Cosmic ray production rates of 10Be and 26Al in quartz from glaciallypolished rocks. Journal of Geophysical Research 94, 17,907e917,915.

Pallàs, R., Rodés, Á, Braucher, R., Carcaillet, J., Ortuño, M., Bordonau, J., Bourlès, D.,Vilaplana, J.M., Masana, E., Santanach, P., 2006. Late Pleistocene and Holoceneglaciation in the Pyrenees: a critical review and new evidence from 10Be expo-sure ages, south-central Pyrenees. Quaternary Science Reviews 25, 2937e2963.

Plug, L.J., Gosse, J.C., McIntosh, J.J., Bigley, R., 2007. Attenuation of cosmic ray flux intemperate forest. Journal ofGeophysical Research112. doi:10.1029/2006JF000668.

V. Rinterknecht et al. / Quaternary Science Reviews 39 (2012) 106e114114

Rasmussen, S.O., Andersen, K.K., Svensson, A.M., Steffensen, J.P., Vinther, B.M.,Clausen, H.B., Siggaard-Andersen, M.L., Johnsen, S.J., Larsen, L.B., Dahl-Jensen, D., Bigler, M., Röthlisberger, R., Fischer, H., Goto-Azuma, K.,Hansson, M.E., Ruth, U., 2006. A new greenland ice core chronology for the lastglacial termination. Journal of Geophysical Research 111, D06102.

Reimer, P.J., Baillie, M.G.L., Bard, E., Bayliss, A., Beck, J.W., Blackwell, P.G., BronkRamsey, C., Buck, C.E., Burr, G.S., Edwards, R.L., Friedrich, M., Grootes, P.M.,Guilderson, T.P., Hajdas, I., Heaton, T.J., Hogg, A.G., Hughen, K.A., Kaiser, K.F.,Kromer, B., McCormac, F.G., Manning, S.W., Reimer, R.W., Richards, D.A.,Southon, J.R., Talamo, S., Turney, C.S.M., van der Plicht, J., Weyhenmeyer, C.E.,2009. IntCal09 and Marine09 radiocarbon age calibration curves, 0e50,000years cal BP. Radiocarbon 51, 1111e1150.

Reuther, A.U., Urdea, P., Geiger, C., Ivy-Ochs, S., Niller, H.-P., Kubik, P.W., Heine, K.,2007. Late Pleistocene glacial chronology of the Pietrele Valley, RetezatMountains, Southern Carpathians constrained by 10Be exposure ages andpedological investigations. Quaternary International 164-165, 151e169.

Rinterknecht, V.R., Clark, P.U., Raisbeck, G.M., Yiou, F., Brook, E.J., Tschudi, S.,Lunkka, J.P., 2004. Cosmogenic 10Be dating of the Salpausselkä I moraine insouthwestern Finland. Quaternary Science Reviews 23, 2283e2289.

Romer, E., 1906. Epoka lodowa na Swidowcu. Rozpravy Ak. Um., Krakow. A 46 (SeriaIII, 6), 11e80.

Saarnisto, M., Saarinen, T., 2001. Deglaciation chronology of the Scandinavian icesheet from the Lake Onega basin to the Salpausselkä end moraines. Global andPlanetary Change 31, 387e405.

Stone, J., 2000. Air pressure and cosmogenic isotope production. Journal ofGeophysical Research 105, 23753e23759.

Stuiver, M., Reimer, P.J., Reimer, R.W., 2005. Accessed 15 September 2011. http://calib.qub.ac.uk/calib/.

Sviderski, B., 1938. Geomorfologia Czarnogory. Warszawa.

Tóth, M., Magyari, E.K., Brooks, S.J., Braun, M., Buczkó, K., Bálint, M., Heiri, O.,2012. A chironomid-based reconstruction of late glacial summer tempera-tures in the southern Carpathians (Romania). Quaternary Research 77,122e131.

Tretyak, P.R., Kuleshko, M.P., 1982. Degradatsiya poslednego oledeneniya vUkrainskih Carpatah (Degradation of the last glaciation in Ukrainian Carpa-thians). Doklady Akademii Nauk Ukr SSR, B 8, 26e31.

Tschudi, S., Ivy-Ochs, S., Schluechter, C., Kubik, P., Rainio, H., 2000. 10Be dating ofyounger Dryas Salpausselka I formation in Finland. Boreas 29, 287e293.

Tsys’, P.N., 1961. Some Problems of the Quaternary Morphogenesis of the SovietCarpathians Quaternary Period 13, vol. 14, pp. 231e239.

Tykhanych, V.V., 1967. K voprosu geomorfologii Svidovtsa (On the Problem of Svydo-vets’ geomorphology) Doklady i soobscheniya L’vovskogo otdela Geo-graphicheskogo obschestva UkrSSR za 1965g. Izdatel’stvo L’vovskogo Universiteta,pp. 97e102.

Urdea, P., 2004. The Pleistocene glaciation of the Romanian Carpathians. In:Ehlers, J., Gibbard, P. (Eds.), Quaternary Glaciations e Extent and Chronology.Part 1: Europe. Elsevier, Amsterdam, pp. 301e308.

Velichko, A.A., Fuastova, M.A., Gribchenko, Y.N., Pisareva, V.V., Sudakova, N.G., 2004.Glaciations of the east European plain - distribution and chronology. In:Ehlers, J., Gibbard, P. (Eds.), Quaternary Glaciations e Extent and Chronology.Part 1: Europe. Elsevier, Amsterdam, pp. 337e354.

Voropai, L.I., Kunytsia, M.O., 1969. Drevneliodoviokovi formy rel’iefu masyvu Svy-dovets’ v Ukrayins’kykh Carpatah (Ancient glacial landforms of Svydovets’massif in Ukrainian Carpathians). Geographichni doslidzhennya na Ukrayini 1,111e125.

Zahno, C., Akçar, N., Yavuz, V., Kubik, P.W., Schlüchter, C., 2010. Chronology of latePleistocene glacier variations at the Uludag Mountain, NW Turkey. QuaternaryScience Reviews 29, 1173e1187.