This article appeared in a journal published by Elsevier. The attachedcopy is furnished to the author for internal non-commercial researchand education use, including for instruction at the authors institution

and sharing with colleagues.

Other uses, including reproduction and distribution, or selling orlicensing copies, or posting to personal, institutional or third party

websites are prohibited.

In most cases authors are permitted to post their version of thearticle (e.g. in Word or Tex form) to their personal website orinstitutional repository. Authors requiring further information

regarding Elsevier’s archiving and manuscript policies areencouraged to visit:

http://www.elsevier.com/copyright

Author's personal copy

Paleoenvironments of the latest Cretaceous oil shale sequence, Southern Tethys,Israel, as an integral part of the prevailing upwelling system

Sarit Ashckenazi-Polivoda a,⁎, Sigal Abramovich a, Ahuva Almogi-Labin b, Aya Schneider-Mor a,Shimon Feinstein a, Wilhelm Püttmann c, Zsolt Berner d

a Department of Geological and Environmental Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israelb Geological Survey of Israel, Jerusalem, Israelc Institutes of Atmospheric and Environmental Sciences, Frankfurt am Main, Germanyd Institutes of Mineralogy and Geochemistry at Fridericiana University of Karlsruhe, TH, Germany

a b s t r a c ta r t i c l e i n f o

Article history:Received 26 August 2010Received in revised form 3 February 2011Accepted 20 February 2011Available online 24 February 2011

Keywords:Oil shaleSouthern TethysLate Cretaceous upwelling systemPlanktic and benthic foraminiferaBiostratigraphy

The Late Cretaceous succession in Israel is part of an extensive high-productivity upwelling regime thatpersisted over ~20 m.y. in the southern margins of Tethys. The deposition of a ~40-m thick organic-richcarbonate (“oil shale”) sequence in the Negev, Israel, indicates a major change in the evolution of this high-productivity regime and reorganization of the marine ecosystem during the latest Campanian–earlyMaastrichtian time. The main objective of this study was to reconstruct changes in surface water productivityand seafloor oxygenation during the deposition of the Oil Shale Member (OSM) and transitions with theunderlying Phosphate and overlying Marl Members using high-resolution records of planktic and benthicforaminifera and total organic carbon (TOC) content. The updated age of the OSM, determined by integratingplanktic foraminifera, calcareous nannofossils and inoceramids, suggests that this sequence spans amaximumof 1.85 m.y. from 71.6 to 69.85 Ma, with a sedimentation rate of at least 2.4 cm/kyr.Five distinct planktic (P-Types) and benthic (B-Type) foraminiferal assemblages were distinguished in thestudied sequence. The change from P-Type 5 to P-Type 1 along the sequence correlates with a distinctdecrease in TOC content (18.0–0.1 wt.%), and signifies an upward decline in surface productivity. Based onthis relationship, it was inferred that species of Globigerinelloides (principally Globigerinelloides asper) are thebest tracers for extreme eutrophic surface water, whereas heterohelicids are associated with moremesotrophic conditions. The transition in time from assemblages B-Types 5 to 1 mainly reflects a changefrom the predominance of praebuliminids and neobuliminids to a more diversified rotaliid-dominatedassemblage, indicating an increase in bottom water aeration. The appearances of planktic foraminiferacoincident with the establishment of benthic rotaliid fauna at the Phosphate-Oil Shale Member transitionmark the most prominent change in the upwelling sequence. This change probably reflects moderateweakening of the eutrophic surface water productivity and a regional sea level rise resulting in seafloordeepening and improved seafloor aeration. A further step in the decrease in TOC content (to 5.5–8 wt.%)occurs in the uppermost part of the OSM (latest Campanian) and corresponds to the transitions toassemblages P-Type 1 and B-Type 1. This change suggests a shift to mesotrophic conditions, additionalincrease in bottom and pore water aeration, and thus the demise of the upwelling activity in the southernTethys.

© 2011 Elsevier B.V. All rights reserved.

1. Introduction

1.1. Marine high productivity settings

The marine high-productivity settings of upwelling systems areoften associated with sediment deposits rich in silica, organic carbon

and phosphorus (Si–C–P). Factors governing the ultimate composi-tion of the rock record of these systems include the type of primaryproducers in the water column (e.g., diatoms, calcareous nanno-plankton, and dinoflagellates). The high nutrient levels associatedwith shelf upwelling system support enhanced production of organicmatter, which reaches the seafloor and result in a significant decreasein oxygen concentration that can reach anoxia. Burial of organicmatter and its decomposition are mainly determined by three factors:1. Sedimentation rates of primary and secondary producers; 2. Lateraltransport of particulate organic matter; and 3. Diagenetic processeswithin the water column and the sediments (Parrish and Curtis, 1982;

Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

⁎ Corresponding author.E-mail address: ashcenaz@bgu.ac.il (S. Ashckenazi-Polivoda).

0031-0182/$ – see front matter © 2011 Elsevier B.V. All rights reserved.doi:10.1016/j.palaeo.2011.02.018

Contents lists available at ScienceDirect

Palaeogeography, Palaeoclimatology, Palaeoecology

j ourna l homepage: www.e lsev ie r.com/ locate /pa laeo

Author's personal copy

Suess and Thiede, 1983; Thiede and Suess, 1983; Summerhayes, et al.,1992; Giraudeau et al., 2000; Monteiro et al., 2005).

The main upwelling systems today are located on the westernmargins of the continents, off North and South America and off Northand South Africa. Wind intensity and direction influence the locationand intensity of the upwelling cells (e.g., Shannon, 1985). Thesediment distribution in modern upwelling regions includes twoprincipal lithologies, namely biosiliceous sediments and organic-richcarbonates, which are deposited according to the upwelling gradient.Diatomaceous sediments with highest concentration of opal (N5%)and organic matter (12–25%) accumulate on the inner shelf, wherephosphorus (N30% francolite) can also accumulate in patches, in areasof maximumupwelling intensity. Calcareous sediments (N50% CaCO3)mainly accumulate in outer shelves where the organic content isrelatively reduced (4–12%) (Bremner, 1983; Bremner and Willis,1993; Bruchert, et al., 2000; Giraudeau et al., 2000; Monteiro et al.,2005; Leiter and Altenbach, 2010).

The complexity of upwelling systems has left many unansweredquestions for both modern and ancient examples. These includefundamental environmental issues, such as the levels of primaryproduction in the water column and of oxygenation in bottom watersduring the accumulation of organic-rich carbonates, phosphates andporcellanites.

1.2. The Late Cretaceous high-productivity sequence in Israel

The Late Cretaceous Israeli marine succession was influenced bytwo major unrelated processes: (1) Deposition in tectonically-controlled, NE-trending shelf basins associated with the Syrian Arcsystem (Krenkel, 1924). This deformation differentiated the outer partof the “ramp-shelf” (nearly 100 km wide) into sub-parallel NE–SWanticlinal ridges and synclinal basins, resulting in lateral changes inthickness and facies. (2) Development of a high-productivityupwelling regime from Santonian to Maastrichtian time along thesouthern margins of the Tethys (Kolodny, 1980; Bein and Amit, 1982;Reiss, 1988; Almogi-Labin et al., 1990a,b; 1993; Bein et al., 1990; Eshetet al., 1994; Kolodny and Garrison, 1994; Eshet and Almogi-Labin,1996; Soudry et al., 2006, Fig. 1A).

Themost intense upwelling phase occurred during themiddle-lateCampanian (Bein et al., 1990; Almogi-Labin et al., 1993). The MishashFormation was deposited in southern Israel throughout this period.This formation consists of two members, the Chert Member at thebase and the Phosphate Member at the top (Soudry et al., 1985). Totalorganic carbon (TOC) content in these rocks is as high as 24 wt.% (Beinet al., 1990). At the top of the Mishash Formation, the lithologychanges into a monotonous sequence of organic rich carbonates (15–20 wt.% TOC) (Bein, et al., 1990; Minster, 1996), locally referred to asthe Oil ShaleMember (OSM). This unit was dated in the Negev as earlyMaastrichtian and defines the lower part of the Ghareb Formation(Reiss et al., 1985; Almogi-Labin et al., 1993).

In the Negev, the oil shale deposits are generally confined tosynclines where they reach a maximal thickness of 40–45 m, and aresignificantly reduced or missing in high structures due to syn- or post-deposition truncation or differential removal of the sediments (Shaharand Wurzburger, 1967; Minster, 1996). Early-middle Maastrichtianpelagic marls and chalks (i.e., the Marl and Chalky Members) mark theend of the organic-rich carbonate sequence and the return of morenormal oceanic conditions in this region (Abramovich et al., 1998,2010).

Offshore, in the central (Shefela) and northern parts of Israel, thehigh-productivity sequence consists mainly of thick (N200 m)

organic-rich carbonates of the Ein Zeitim Formation, which wasdeposited marginal to the upwelling center. The age of this unitcoincides with the interval of the Mishash Formation and lower andmiddle parts of the Ghareb Formation (OSM and Marl Mbr) in theNegev (Flexer, 1968; Bein et al., 1990; Almogi-Labin et al., 1993).

Recently, Soudry et al. (2006) have demonstrated that theevolution of this upwelling system was driven by the combined effectof global post-Santonian cooling, sea level highstands, and platemovement. As a result, a westward circum-global surface and deepwater circulation pattern developed along the southern margins ofthe Tethys. The intensity and persistence of this upwelling systemmake it arguably one of the most productive in the Earth's history anda prototype for similar systems of ancient and recent marineenvironments (Parrish, 1998).

The main objective of the present research was to establish thebiotic records of benthic and planktic foraminifera of the last phase ofthe Southern Tethys high-productivity succession. These recordsmade it possible to reconstruct the changes in surface waterproductivity and seafloor oxygenation that occurred during deposi-tion of the OSM as well as during the transitions from the underlyingPhosphate and to the overlying Marl Member. Another objective wasto establish a high-resolution biostratigraphic scheme based on themost updated Late Cretaceous planktic foraminiferal zonation. Thisscheme allowed us to determine the duration of the final stage of theprevailing upwelling system and helped us situate it in a globalpaleoceanographic context.

2. Materials and methods

2.1. Location of samples

The extended lithological sequence of the high-productivitysuccession exposed at the open PAMA quarry was chosen for thisstudy as a representative section of the Negev oil shale deposits. Thisquarry is located at Mishor Rotem (Efe Syncline; 31°04′51.82″N;35°10′02.85″E), where the largest oil shale reservoir in Israel is found(Fig. 1B). Unlike most of the Negev OSM outcrops, the sequenceexposed at PAMA quarry is fresh and unaltered, exhibits low thermalmaturity, and contains well-preserved fossils.

About 100 samples were taken at approximately 20 cm to 1 mintervals from the ~50 m sequence exposed at the quarry, whichincludes the uppermost part of the Phosphate Mbr of the MishashFormation (5.6 m), the entire OSM (42 m), and the base of the MarlMbr (~3 m) of the Ghareb Formation. The present study focused on amicropaleontological investigation of these samples. Schneider-Moret al. (in preparation) used the same sample set for a detailedgeochemical analysis (TOC, stable isotopes of carbonate and organicmatter) of this sequence.

2.2. Sample analyses

For the micropaleontology analyses the samples were disaggre-gated and soaked in a 10–20% sodium hypochlorite solution at 50 °Cfor 2–3 days to remove the organic coating from the calcareous shells,washed through N63 μm sieve, and dried in the oven at 50 °C. Thestate of preservation of the foraminiferal tests is usually very goodthroughout the studied sequence. From each sample, about 200–300planktic and ~200–300 benthic foraminiferal specimens from theN63 μm size fraction were picked from a split aliquot representing theentire sample. Specimens were identified and counted to evaluate the

Fig. 1. A. Paleogeography map shows the upwelling belts developed along the Southern Tethys margin during the Late Campanian and Early Maastrichtian (modified after Parrishand Curtis, 1982). Star marks the inferred position of Negev region within the Levant upwelling belt. B. Geological map (1:250,000) of northern Negev modified after Shahar andWurzburger, 1967. The PAMA Quarry is located in the Efe Syncline, where the largest oil shale reservoir of southern Israel occurs.

94 S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

95S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

relative abundance of each species. Several parameters were calcu-lated based on the relative abundance database.

The abundance ratio of Globigerinelloides Cushman and ten Dam/Heterohelix Ehrenberg (G/H), two common planktic genera, the P/Bratio (planktic/planktic+benthic foraminifera), and clustering ofplanktic foraminiferal assemblages (P-Types) were used to infer theproductivity level in the surface water. The abundance ratio ofbuliminids (this group includes Bolivina d'Orbigny, BolivinoidesCushman, Eouvigerina Cushman, Loxostomum Ehrenberg, NeobuliminaCushman and Wickenden, Praebulimina Hofker and SiphogenerinoidesCushman) to rotaliids (this group includes Alabamina ToulminAngulogavelinella Hofker, Cibicides de Montfort, Gavelinella BrotzenGyroidinoides Brotzen, Nonionella Cushman, Osangularia Brotzen andSliteria Gawor-Biedowa) (B/R), and clustering of benthic foraminiferalassemblages (B-Types) were used for estimating the variability inbottom water aeration.

Planktic andbenthic foraminiferal assemblages (P-Types andB-Types)were defined by cluster analysis based on the relative abundance of theplanktic and benthic foraminiferal genera from all analyzed samples.Using PRIMERv6 software (PRIMER-E Ltd, Plymouth, UK),wegenerated asimilarity matrix comprising Bray–Curtis similarity coefficients of all thepossible pairwise samples. Each of these coefficients represents theresemblance between two samples. To find the ‘natural groups’ of theanalyzed samples, namely when expression profiles within a group aremore similar to each other than to profiles in different groups, we usedhierarchical agglomerative clustering. This was followed by a series of‘similarity profile’ (SIMPROF) permutation tests intended to revealstatistically significant evidence for genuine clusters in the generateddendrogram. Specifically, tests were performed at every node of thecomputed dendrogram such that the group being subdivided hadsignificant (Pb0.05) internal structure. Finally, to assess the contributionof eachof theplanktic or benthic foraminiferal genera examined to eachofthe significantly detected expression clusters we used the ‘similarity

percentages’ routine (SIMPER), which decomposes average Bray–Curtisdissimilarities into percentage contributions.

3. Results

3.1. Biostratigraphy

The biostratigraphy used in this study is based on integration ofthe high resolution Cretaceous foraminifera (CF) biozonation of Li andKeller (1998a,b, 1999) and the recent biostratigraphic study of Huberet al. (2008). These subdivisions, together with the updatedchronostratigraphy of Gradstein et al. (2005), are given in Fig. 2.

The OSM ranges from the latest Campanian to the earlyMaastrichtianPseudoguembelina palpebra Zone (Huber et al., 2008), the time equivalentof CF8b–CF7 of Li and Keller (1998a,b). The time constraint for the base ofthe OSM was determined by the first appearances (FA) of P. palpebra(Brönnimann and Brown), Rugoglobigerina macrocephala (Brönnimann),Globotruncanita pettersi (Gandolfi), and Pseudoguembelina kempensis(Esker). The ageof the topof theOSMwasdefinedby the last appearances(LA) of Quadrum trifidumHattner andWise, by Fiorentino (1995), 1–2 mbelow the OSM-Marl Mbr transition at a nearby location.

3.2. Lithology

The top of the Phosphate Mbr consists of brownish-gray granulatedphosphates (carbonate-fluorapatite) with TOC values mostly rangingbetween 1 and 4 wt.% (Fig. 3). Its phosphate fraction mainly consists ofsub-millimetric ovoid grains (peloids), bone fragments and fecal pellets.A 0.9 m thick light-brown condensed carbonate marks the top of thePhosphate Mbr. It consists of 20% dolomite, 45% fluorapatite, and 30%calcite, and 1–2 wt.%, TOC (Bein et al., 1990). This unit is recognized as aregional condensation interval with no foraminiferal remains. Theoverlying OSM is a monotonous unit consisting of dark-gray organic-

Fig. 2. Comparisonof commonlyusedUpperCampanian–Maastrichtianplanktic foraminiferal biozonationand theFAs (first appearances) andLAs (last appearances)ofbiomarkers used inthese zonations and in this study (right column). Ages ofmagnetostratigraphic chronswere recalibrated and adjusted to time scale ofGradstein et al. (2005). Absolute ages of biozonationsof Robaszynski et al. (1984), Almogi-Labin et al. (1993) andHuber et al. (2008) and of CF (Cretaceous foram) Zone datums (base of zone) of Li and Keller (1998a, 1998b)were recalculatedto correspond to updates of Gradstein et al. (2005). OA— original age, RA— revised age. Black arrow— FA or LA of biostratigraphicmarkers. Gray arrow— secondary planktic foraminiferalmarkers. C/M — Campanian–Maastrichtian boundary following: 1. Robaszynski et al. (1984); 2. Haq et al. (1987); 3. Gradstein et al. (1994); and 4. Gradstein et al. (2005).

96 S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

rich carbonatemudstone (50–75% CaCO3),with amacrofauna includingInocermus occurring at discrete intervals throughout. There is a distinctstep-wise decrease in TOC content from the base to the top of the OSM,the highest values (up to 18 wt.%) being found in its lower part (43.8–37.0 m)and intermediate values (mostly 9–11 wt.%) at 37.0 to13.0 m.Afurther drop in TOC values is recorded in the top section of the OSMbetween 13.0 and 3.0 m, where values are mostly 5.5–8 wt.%. Thecontact with the overlying Marl Mbr is marked by a sharp change incolor to light-yellow marly chalk with TOC values below 1.0 wt.%, withno evidence of a diastem or hiatus (Fig. 3).

3.3. Foraminiferal species richness and abundances

3.3.1. Planktic foraminiferaPlanktic foraminifera rarely occur in the top section of the Phosphate

Mbr, and when present display very low species richness values of ~5species. Their numbers and diversity increase dramatically at the base ofthe OSM, ranging up to 7500 specimens/g dry sediment and 16 species,respectively (Fig. 4). While this is followed upwards by a 3 m interval(41–38 m)where values are less than 160 specimens/gdry sediment, asone rises along the OSM sequence the numerical abundance increasesonce more, although fluctuating widely (from a minimum of ~500 to amaximum of ~2500 specimens/g dry sediment). At the transition to theoverlying Marl Mbr the numerical abundance of the planktic forami-nifera increases further, stabilizing at ~3000 specimens/g dry sediment.

There is a slight increase in species richness toward the middle and topof the OSM, where values generally vary between 20 and 24 species ascompared with 11–16 in the lower section.

The fewspecimens thatwere found in the topsectionof thePhosphateMbrmostly belong toGlobigerinelloides (Fig. 4). This groupalsodominatesthe lower section of the OSM (40–60% of total planktics), withGlobigerinelloides asper (Ehrenberg) the most common species of thisgenus. Heterohelix becomes dominant in the middle and upper parts ofthe OSMand at the base of theMarlMbr (55–85% of total planktics), withHeterohelix globulosa (Ehrenberg) andHeterohelix planata (Cushman) themost common species. Laeviheterohelix Nederbragt species are relativelycommon throughout the studied sequence (up to 13%). The relativeabundance of Hedbergella Brönnimann and Brown increases from ~10%in the lower part of the OSM to mostly over 20% in the upper part of theOSM and lower part of the Marl Mbr. Keeled globotruncanids,Pseudoguembelina Brönnimann and Brown, Archaeoglobigerina Pessagno,and Rugoglobigerina Brönnimann appear near the base of the OSM butremain rare throughout the entire sequence. Racemiguembelina Mon-tanaro Gallitelli species are not present.

A general decrease in Globigerinelloides/Heterohelix (G/H) ratio isobserved ascending from the top section of the Phosphate Mbr andlowerOSM toward the upperOSMand base of theMarlMbr (Fig. 4). ThePhosphate Mbr and the lower part of the OSM (up to 38 m) are mostlycharacterized by relatively highG/H ratios (~70%). The only exception isthe interval from 43.8 to 42.5 m, where values temporarily drop to less

Fig. 3. Stratigraphy, lithology, and TOC content of studied section at PAMA Quarry. Note distinct lithological change from dark colored OSM to light colored Marl Member coincidentwith sharp drop in TOC content.

97S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

than 50% coincidentwith high planktic foraminiferal abundances. In themiddle section of the OSM (38–27 m), the G/H ratio ranges from 30 to45%, and a further decrease occurs in the upper part of the sequence,where it fluctuates between 5 and 20%.

3.3.2. Benthic foraminiferaBenthic foraminifera are very common (6500 specimens/g dry

sediment) at the top of the Phosphate Mbr, although with low speciesrichness (4–8 species). Their numerical abundance decreases signifi-cantly over the OSM and Marl Mbr to 300–1500 specimens/g drysediment. Species richness increases gradually from the base of theOSM(43.8–43.0 m) to its middle section (~34 m, 16 to 23 species) andupwards through the rest of the sequence (26 to 40 species).

The top section of the Phosphate Mbr is characterized by thedominance of buliminids (98% of total benthic foraminifera) comprisinga single species, Praebulimina prolixa (Cushman and Parker) (Fig. 5). Atthe base of the OSM (43.8–43.0 m) buliminids decline sharply to 34%and rotaliids consisting mainly of Gavelinella and Gyroidinoides becomedominant (56–65%). From 42 to 38 m the relative abundance of thebuliminids rises temporarily to 55–80%. Throughout the rest of the OSMand in the overlying Marl Mbr buliminids decline to 20–40% of thebenthic foraminiferal assemblage, rotaliids represented by Gavelinella,Gyroidinoides and Sliteria, become the predominant component(50–75%). Changes in the relative abundance of the two dominantgroups are reflected in variations in the buliminid/rotaliid (B/R) ratio.This ratio fluctuates strongly at the base of the OSM from amaximumof90% to a minimum of 32%, then remains relatively low (9–20%)throughout the remainder of the OSM and in the Marl Mbr (Fig. 5). Theupward decrease in the numerical abundance of buliminids is alsoaccompanied by a shift in species composition. Praebuliminids andNeobuliminids are the most common groups in the topmost part of thePhosphate Mbr and lower part of the OSM (98–42% of total benthicforaminifera), whereas Eouvigerininds dominate the buliminid assem-

blages in the middle and upper parts of the OSM and in the Marl Mbr(~10% of total benthic foraminifera).

Agglutinants are absent at the top of the Phosphate Mbr and in thelower part of the OSM. They appear at 40 m (mainly Dorothia Plummer,Arenobulimina Cushman, Verneuilina d'Orbigny, and SpiroplectamminaCushman), and remain moderately common (1-12%) throughout theOSMandMarlMbr,with somewhat higher values in the upper part of thesequence (Fig. 5). Uniserial nodosarids (Dentalina Risso, LaevidentalinaLoeblich and Tappan and Nodosaria Lamarck) are found in very smallnumbers (~2%) in the top section of the Phosphate Mbr and becomemore common (up to 15%) in the OSM and Marl Mbr. Miliolids(Quinqueloculina d'Orbigny and Triloculina d'Orbigny) first appear inthe middle part of the OSM (34 m) and remain very rare throughout therest of the sequence.

3.4. P/B ratio

In the top section of the Phosphate Mbr (49–46 m) the P/B ratio isvery low, with benthic foraminifera comprising 97% of the foraminiferalassemblage (Fig. 5). Planktic foraminifera appear abruptly at the base ofthe OSM (43.8 m), where they comprise nearly 80% of the foraminiferalassemblage. About 3 m above the base of theOSM (41–38 m), P/B ratiostemporarily drop to less than5%. This decrease is followed by a stepwiseincrease to ~70% at 35 m. P/B ratio remains high (mostly N50%,maximum of 80%) in the middle and upper parts of the OSM and at thebase of the Marl Mbr.

3.5. Planktic foraminiferal assemblages—P-Types

Five distinct planktic foraminiferal assemblages (P-Types 1–5)were identified in the studied section based on the statisticalclustering of the planktic foraminiferal genera. The calculatedcomplete linkages and similarity percentages (SIMPER) are presented

5

10

15

20

25

30

35

40

45

Fig. 4. Planktic foraminifera numerical abundance, species richness, relative abundances of major genera and Globigerinelloides/Heterohelix (G/H) ratio in the studied section. Notegradual decrease in relative abundance of Globigerinelloides toward the top of the OSM.

98 S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

in Fig. 6. Dissimilarity percentages between the P-Type assemblagesare presented in Table 1. SIMPER test revealed that the generaGlobigerinelloides, Heterohelix and Hedbergella are the main contribu-tors to clustering for the five assemblages (Fig. 6). The greatestdissimilarity was measured between assemblage Type 5 and Types 1,2, 3 (Table 1).

Assemblage Type 5 is the only one characterized by dominance ofGlobigerinelloides (87%), the main contributor of similarity between thesamples of this assemblage and of dissimilarity from the otherassemblages (Fig. 6, Table 1). Assemblage Type 4 is also characterizedby relatively high abundance of Globigerinelloides (50%), and increase inHeterohelix abundance (27%). Heterohelix is the main contributor ofsimilarities between assemblage P-Types 4 and 1 (Fig. 6). Variations inthe abundance of these two genera are themain sources of dissimilaritybetween assemblages P-Types 4 and 2. Assemblage P-Type 2 isdistinguished from all the other assemblages by the high abundanceand contribution of Hedbergella (28% and 31% respectively) to thesimilarity of the samples.

3.6. Benthic foraminiferal assemblages—B-Types

Five benthic foraminiferal assemblages (B-Types) were definedbased on the statistical clustering of the benthic foraminiferal genera(Fig. 7, Table 2). Four assemblages (B-Types 1–4) characterize most ofthe analyzed samples. Assemblage B-Type 5 is represented by only twosamples (Fig. 7). The abundance data for the triserial buliminidPraebulimina and Neobulimina were combined for the statisticalanalysis. SIMPER test showed that the triserial buliminids,Gyroidinoidesand Gavelinella are the main contributors to clustering of theseassemblages. Thegreatest dissimilaritywas foundbetweenassemblages

B-Type 5 and the other four and is contributed by the variation inabundance of the triserial buliminids (Fig. 7).

Assemblages B-Type 5 and 4 are distinguished by the dominance oftriserial buliminids and the main contributors of the similaritybetween the samples of these assemblages. Gyroidinoides are themain contributor of similarities within assemblages B-Types 3 to 1(Fig. 7, Table 2).

4. Discussion

4.1. Biostratigraphy

The age of the OSM was determined based on integration ofprimary and secondary planktic foraminiferal data and occurrences ofcalcareous nannofossils and inoceramid bivalves. The entire OSM isconfined to the undifferentiated zonal interval CF8a–CF7 of Li andKeller (1998a,b), which corresponds to the new Pseudoguembelinapalpebra Zone of Huber et al. (2008).

The exact age of the base of the OSM could not be ascertainedprecisely. This is partially due to the late FA in Israel of the index taxaof CF7 and CF8b, Rugoglobigerina hexacamerata Brönnimann andGansserina gansseri (Bolli) (see also Almogi-Labin et al., 1993;Abramovich et al., 1998; Abramovich et al., 2010). Moreover, thenearly 1 m thick hardground/condensed interval at the top of thePhosphate Mbr that underlies the OSM most likely represents asubstantial hiatus. Therefore, the observed FAs of index plankticforaminiferal species at the base of the OSM do not necessarilyrepresent their true evolutionary appearances.

The secondary biostratigraphic markers Rugoglobigerina macro-cephala Brönnimann and Globotruncanita pettersi (Gandolfi) occurfrom the base of the OSM. According to Robaszynski et al. (1984), the

20%50%

10%

Fig. 5. Benthic foraminifera numerical abundance, species richness, relative abundances of major genera, % buliminids/rotaliids (B/R) and % planktic foraminifera/benthicforaminifera (P/B) in the studied section. Note decrease in buliminids toward the top of the OSM.

99S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

FAs of R. macrocephala and G. pettersi coincide approximately with theFA of Gansserina gansseri, which was dated at 70.4 Ma. However,Huber et al. (2008) reported a much older age for the FA of G. gansseri,72.35 Ma, and suggested a new Pseudoguembelina palpebra Partial-Range Zone for this interval that spans the period from 71.64 to69.62 Ma, from the FA of P. palpebra to the FA of Racemiguembelinafructicosa (Egger). The FA of Pseudoguembelina kempensis Esker, at71.5 Ma, was suggested as a secondary biomarker for the lower part ofthis Zone. Pseudoguembelina palpebra occurs in the studied sequencefrom the base of the OSM, indicating that the age of this level is notolder than 71.64 Ma. This age estimation is further supported by thepresence of P. kempensis in the lower part of the OSM (depth 35 m,Fig. 2).

The age of the top of the OSM in the Negev could bemore preciselydetermined. The LA of Quadrum trifidum had previously beenidentified by Fiorentino (1995) 1–2 m below the OSM-Marl Mbrtransition at a nearby location at Hor Hahar, indicating that the top ofthe OSM could not be much younger than 69.85 Ma (see Odin andLamaurelle, 2001; Huber et al., 2008).

Inoceramid bivalves provide another indication of the age of thisunit. The global extinction of this group has been found to coincidewith the end of the early-Maastrichtianwarm event (MacLeod, 1994a,b; Frank et al., 2005). Their extinction was dated by Huber et al.(2008) between 68.5 and 68.7 Ma. Inoceramids are relativelycommon throughout the OSM, indicating that the end of thedeposition of this unit occurred prior to their global extinction.

Fig. 6. Dendrogram showing the five P-Types (planktic foram assemblages) distinguished in the statistical cluster analysis. The results of the SIMPER test are presented by dominantgenus abundance and their contribution (in brackets) to similarity within the assemblage.

Table 1Average dissimilarity and the contribution of the main groups to the dissimilaritybetween the different P-Type assemblages (1–5), as shown by the SIMPER test.

P-Type 1 2 3 4

2 Globigerinelloides 11.33Heterohelix 29.56Hedbergella 34.32Hartella 4.77Laeviheterohelix 4.58Pseudoguembelina 3.53Average dissimilarity 23.88

3 Globigerinelloides 44.86 42.11Heterohelix 20.39 7.53Hedbergella 13.13 32.72Hartella 4.51 3.32Laeviheterohelix 3.86 2.37Pseudoguembelina 3.07 2.76Average dissimilarity 31.44 35.76

4 Globigerinelloides 46.08 47.97 30.48Heterohelix 31.33 19.62 34.72Hedbergella 6.24 16.02 13.70Hartella 3.06 2.57 –

Laeviheterohelix 3.02 – 4.25Pseudoguembelina 2.34 3.33 4.16Average dissimilarity 46.09 46.25 23.35

5 Globigerinelloides 50.92 50.97 50.09 52.04Heterohelix 28.42 18.45 31.31 21.16Hedbergella 6.02 16.49 4.12 10.86Hartella – – – 5.93Laeviheterohelix 3.65 2.87 4.54 7.94Pseudoguembelina 3.05 3.24 – –

Average dissimilarity 72.75 74.50 46.04 30.92

100 S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

Several datum events associated with planktic foraminifera occur inthe lower part of theMarlMbr, indicating that the top of theOSMmust beolder. For example, the global extinctions of Globotruncana linneiana(d'Orbigny), Globotruncana bulloides Vogler and Contustruncana fornicata(Plummer) were documented in the Negev in the lower part of the MarlMbr (Abramovich et al., 1998). These extinction events were dated byHuberet al. (2008)at67.86, 68.34and68.66 Ma, respectively. Li andKeller(1998a,b) reported amuch older age for the LA of G. linneiana at 69.1 Ma.The FA of Pseudotextularia elegans (Rzehak), now dated at 69.02 Ma(Huber et al., 2008), was documented in the lower–middle parts of theMarl Mbr, below the last occurrence of G. linneiana, G. bulloides andC. fornicata (Abramovich et al., 1998).

These findings suggest that the maximum age range of the OSM inthe Negev is between 71.6 Ma (FA of Pseudoguembelina palpebra) and69.85 Ma (LA of Quadrum trifidum). This gives a minimum accumu-lation rate of 2.4 cm/kyr for the entire unit. However, since the base ofthe OSM could be younger than estimated, this unit may have beendeposited within a much shorter time span.

4.2. P-Type assemblages and fluctuations in surface water productivity

Planktic foraminifera are sensitive recorders of the upper part ofthe water column, reflecting changes in primary productivity, seasurface temperature, and degree of water column stratification

(Leckie, 1987; Hemleben et al., 1989; Schiebel and Hemleben,2000). Living planktic foraminifera were found to respond quicklyto seasonal hydrographic changes in upwelling systems off Peru–Chileand off Somalia and Oman in the Arabian Sea (Conan and Brummer,2000; Schiebel et al., 2004; Mohtadi et al., 2005). During periods ofhigh water-column fertility, certain species proliferate while othersdisappear, drastically altering standing stocks and the biodiversityand assemblage composition of the group.

The abrupt reappearance of planktic foraminifera at the base of theOSM signifies a major change in the dynamics of the high-productivityupwelling system. The planktic foraminiferal assemblages show adistinct affinity for high water-column fertility, although this affinitybecomes somewhat weaker in time. In this study we distinguished fivestatistically significant planktic foraminiferal assemblages (P-Types)reflecting changes during deposition of the OSM. A distinct transitionfrom assemblage P-Type 5 to P-Type 1 takes place from the top of thePhosphate to the base of the Marl Mbr (Fig. 8). This transition coincideswith a decrease in TOC contents along the OSM and the Marl Member,from~17 wt.% to0.1 wt.%, and indicates a linkagebetween foraminiferalassemblage composition and upper-water-column productivity.

Assemblage P-Type 5 characterizes the top section of thePhosphate Mbr (Fig. 8), and exhibits the highest occurrences ofGlobigerinelloides (87%) and lowest occurrences of heterohelicids (9%)in the sequence, as well as an absence of keeled globotruncanids and a

Fig. 7. Dendrogram showing the five B-Types (benthic foram assemblages) distinguished in the statistical cluster analysis. The results of the SIMPER test are presented by dominantgenus abundance and their contribution (in brackets) to similarity within the assemblage.

101S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

low P/B ratio (3–22%; Table 3). Globigerinelloides dominate assem-blage P-Type 4 but its abundance is somewhat reduced (51%), thisassemblage defines a 4 m interval 1 m above the base of the OSM(42.6–38.2 m). The highest TOC values were found to correspond tothe intervals defined by assemblage P-Type 4, suggesting that thelatter represent the most intensive phase of water-column produc-tivity in the OSM (~16 wt.%; Fig. 8, Table 3).

Assemblage P-Type 3 defines most of the lower (44.2–43 m) andmiddle (37.6–26.6 m) parts of the OSM. The upper part of the OSMand the Marl Mbr (26.6–0 m) are mostly characterized by fluctuationsbetween assemblages P-Type 2 and P-Type 1. This stratigraphicchange is reflected in a decrease in the abundance of Globigerinelloides(down to 7%) and in TOC content (5 wt.% in the top section of theOSM, 0.1 wt.% in the Marl Mbr) and a concomitant increase inheterohelicids (up to 55%) and P/B (up to 67%). This pattern signifies adistinct decline in surface water productivity from the base of theOSM to the Marl Mbr.

The very high occurrences of Globigerinelloides (50–90%; Fig. 4,Table 2) in assemblages P-Type 5 and P-Type 4 seem to be unique tothe southern Tethyan upwelling regime and have not been docu-mented elsewhere (see also Almogi-Labin et al., 1993). The totalabundances of this genus in the Late Cretaceous are typically lowerthan 5% and rarely exceed 20%. For example, throughout most of theCampanian and Maastrichtian in the oligotrophic environment ofTunisia (Abramovich and Keller, 2002), Globigerinelloides account forless than 1% of the total assemblage. In the South Atlantic DSDP Hole525A, abundances of the most common species Globigerinelloidesasper, range up to 20% during this time interval (Li and Keller, 1998a,b; Frank et al., 2005). These observations, taken together with thestrong coincidence between maximum TOC levels and the dominance

of Globigerinelloides (Fig. 9), suggest that this genus thrives duringtimes of very high surface water productivity.

Heterohelicids display high abundances in a variety of marineenvironments and an ability to adjust to a wide range of water-column conditions. They are among the most common and diverseLate Cretaceous groups and are particularly abundant (N50%) in shelf-slope environments (see summary in Abramovich et al., 2010). Anincrease in the relative abundance of small-sized heterohelicids isoften interpreted as pointing to expansion of the oxygen minimumzone (OMZ) due to increased surface water productivity anddepletion of oxygen in subsurface waters by oxidation of organiccarbon (Leckie, 1987; Barrera and Keller, 1990; Kroon and Nederbragt,1990; Leckie et al., 1998; Keller and Pardo, 2004; Frank et al., 2005;Pardo and Keller, 2008). Heterohelicids were found to be verycommon inmost of the OSM, suggesting a linkage to high productivityor to some degree of tolerance to subsurface oxygen depletion.However, the highest occurrences of this group were found in OSMintervals with lower TOC levels (b10 wt.%; Fig. 9) and a morediversified assemblage that includes keeled globotruncanids, whereashigher TOC levels were associated with dominance of Globigerinel-loides spp. A similar trendwas found by Almogi-Labin et al. (1993) in astudy of the high-productivity sequence in central and southern Israel.These results suggest that Globigerinelloides species are more sensitivetracers for extreme eutrophic conditions in the Late Cretaceous, suchas those that prevailed in the lower part of the OSM, whereasheterohelicids are associated with more mesotrophic conditions.

Keeled globotruncanids are absent in assemblage P-Type 5 andappear in very small numbers (b2%) in assemblage P-Types 4 to 1. Asintermediate- to deep-water dwellers (D'Hondt and Arthur, 1995;Abramovich et al., 2003), they were presumably sensitive tofluctuations of the OMZ (Hart, 1980; Caron and Homewood, 1983;Leckie, 1987; Almogi-Labin et al., 1993; Abramovich and Keller, 2003).Their absence in the lower part of the OSM indicates unsuitableenvironmental conditions, probably reflecting expansion of the OMZrather than shallowwater depths. This notion is also supported by thepresence of typical middle bathyal to upper abyssal benthicforaminiferal species in the OSM (Table 4). Therefore the scarcity ofkeeled globotruncanids in the middle and upper parts of the OSMsuggests that the oxygen content at intermediate water depthsremained unfavorable for this group throughout the period ofdeposition of the OSM.

4.3. B-Type assemblages and seafloor conditions

Upwelling settings are generally associated with high upper-water-column productivity and an oxygen depleted seafloor (Parrishand Curtis, 1982; Suess and Thiede, 1983; Thiede and Suess, 1983;Summerhayes, et al., 1992). Under these conditions the typical well-aerated benthic foraminiferal assemblages (e.g., Widmark, 2000;Alegret and Thomas, 2001; Alegret et al., 2001) disappear, leavingonly some species with special morphological and cytologicaladaptations to these stressed conditions (Leutenegger and Hansen,1979; Bernhard, 1986; Kaiho, 1994; Bernhard, 1996; Bernhard andSen Gupta, 1999; Jorissen, 1999b; Loubere and Fariduddin, 1999;Leckie and Olson, 2003).

The benthic foraminiferal assemblages of the OSM are quitedistinct from their Late Cretaceous counterparts in oligotrophic shelfand open ocean environments, such as those found inMexico, Tunisia,North Atlantic and North Pacific (Li and Keller, 1999; Alegret et al.,2001; Frank et al., 2005; Friedrich and Hemleben, 2007). The benthicforaminiferal assemblages at these localities are more diverse andconsist mostly of epifaunal and shallow infaunal species. The benthicassemblage of the OSM (Table 4), on the other hand, is represented byinfaunal species (triserial buliminids) in its lower part and epifaunalspecies (mostly rotaliids) in its middle and upper parts, indicating anupward transition from nearly anoxic high food flux conditions at the

Table 2Average dissimilarity and the contribution of the main groups to the dissimilaritybetween the different B-Type assemblages (1–5), as shown by the SIMPER test.

B-Type 1 2 3 4

2 Gyroidinoides 26.47Triserial buliminids 10.56Gavelinella 10.71Eouvigerina 10.25Bolivina 10.33Uniserial nodosarids 5.34Agglutinants 8.22Sliteria 9.95Average dissimilarity 27.46

3 Gyroidinoides 8.66 21.36Triserial buliminids 12.26 22.87Gavelinella 11.81 12.76Eouvigerina 8.11 9.59Bolivina 10.35 10.87Uniserial nodosarids 5.3 6.51Agglutinants 9.5 3.37Sliteria 12.06 4.95Average dissimilarity 28.68 25.84

4 Gyroidinoides 16.58 29.6 25.9Triserial buliminids 29.77 27.59 22.69Gavelinella 17.82 19.32 23.36Eouvigerina 9.11 4.85 11.79Bolivina 5.71 5.59 –

Uniserial nodosarids – 3.44 4.55Agglutinants 5.63 – –

Sliteria 6.74 – –

Average dissimilarity 56.24 54.7 41.265 Gyroidinoides 19.29 28.45 25.46 15.35

Triserial buliminids 50.34 50.25 50.42 51.34Gavelinella 7.43 6.7 9.41 26.81Eouvigerina 5.74 3.11 – –

Bolivina 4.43 4.34 – –

Uniserial nodosarids – – 6.53 –

Agglutinants – – – –

Sliteria 4.21 – – –

Average dissimilarity 88.35 85.27 73.8 55.39

102 S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

base of the study sequence to high food flux (mesotrophic conditions)and reasonable aeration at the seafloor at the top (e.g., Jorissen et al.,1995; Jorissen, 1999b; Gooday, 2003; Alegret and Thomas, 2005).

There is a distinct shift from outer shelf triserial buliminid dominatedassemblages (B-Types 5–4) at the top of the Phosphate Mbr and base ofthe OSM to a more diverse assemblage with abundant upper-middlebathyal eouvigerinds, rotaliids (Gyroidinoides,Gavelinella and Sliteria) andsome agglutinants up section through the OSM (B-Types 2 and 1; Fig. 8,Table 4). This shift signifies an overall upward increase in bottom wateraeration under relatively constant and high food supply, possibly togetherwith some seafloor deepening during the transition from B-Types 5–4 to3–1.

Assemblage B-Type 5 indicates extreme depletion of oxygen at theseafloor during deposition of the top of the Phosphate Mbr and ischaracterized by dominance of triserial buliminids (98%) andespecially of Praebulimina prolixa, very high B/R ratios, and very lowP/B ratios (Fig. 8; Table 5). The relatively low TOC content (4 wt.%) istypical for phosphate-rich intervals. Organic-rich carbonates thatoccur between these phosphates are rich in TOC, which can be as highas 24 wt.% (Bein et al., 1990).

The base of the OSMmarks a transition from assemblages B-Types5 to 4, where triserial buliminids (Neobulimina and Praebulimina)decline sharply though remaining dominant (42%), and rotaliids(mostly Gavelinella and to lesser degree Gyroidinoides) becomeabundant. This transition stage is characterized by a decrease in B/Rratio and correspondingly relatively low P/B ratio, as well as bymaximum TOC values (15 wt.%), suggesting a moderate increase inbottom water aeration (Fig. 8; Table 5).

The interval between 38 m and 33 m exhibits a rapid shift fromB-Types 4 to 1, expressed in the establishment of rotaliid domi-nated assemblages and the replacement of triserial buliminids byEouvigerina. From 33 to 9 m the assemblage composition fluctuatesbetween B-Types 2 and 1. The uppermost part of the OSM and lowerpart of the Marl Mbr (top 9 m of the sequence) are defined solelyby assemblage B-Type 1. Assemblages B Types 2 and 1 are bothcharacterized by a relatively low B/R ratio, high P/B ratio, and lowerTOC content (9–7 wt.% in the OSM and 0.1 wt.% in the Marl Mbr,Table 5). The two types are interpreted as representing the mostaerated bottom water conditions in this sequence. The absenceof differences in B-type between the top OSM and base Marl Mbrsuggests that the low TOC level at the base of the Marl Mbr reflectslate diagenetic oxygenation of the apparently higher TOC content inthe unaltered rocks.

Buliminids have repeatedly been found in the geological record inassociation with a high and fairly stable food supply and/or low levelsof oxygen at the seafloor, contrary to most rotaliids, which favoredoxygenated bottom water (Reiss, 1962; Luz and Reiss, 1983;Bernhard, 1986; Almogi-Labin et al., 1993; Sen Gupta and Machain-Castillo, 1993; Kaiho, 1994; Bernhard et al., 1997; Leckie et al., 1998).That is why the buliminids to rotaliids ratio is often used to determinethe oxygenation level of the bottom water in modern and ancientsediments (Nyong and Olsson, 1984; Almogi-Labin et al., 1993).Within the buliminids group, Neobulimina and Praebulimina (triserialbuliminids) are regarded as infaunal species indicative of a very low-oxygenated seafloor and higher organic matter fluxes (e.g., Holbournet al., 1999a,b, 2001; Friedrich et al., 2006; Friedrich, 2009). Moreover,

5

10

15

20

25

30

35

40

45

Fig. 8. Changes in TOC content and P-Type and B-Type trends along the studied section and their paleoenvironmental and paleoceanographic implications. The parallel trends reveala strong linkage between surface and bottomwater conditions. In the light of this linkage, the findings point to a decline in surface water productivity from eutrophic to mesotrophicand an increase in bottom water aeration over the entire sequence including the top of the Phosphate Mbr, the OSM, and the base of the Marl Mbr. Sea level curve is adopted fromMiller et al. (2005) and Kominz et al. (2008).

103S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

predominance of Praebulimina prolixa in the Upper CampanianMishash Formation of southern Israel was singled out by Ashck-enazi-Polivoda et al. (2010) as a sensitive marker indicative of thelow-oxygen pore waters (inferred b0.1 ml O2/l) that developedbeneath the upwelling belt prevailing during this period in theSouthern Tethys.

The shallow infaunal Eouvigerina species (see Alegret and Thomas,2009) is regarded as best adapted to upper–middle bathyal environ-ments with relatively high food supply but reasonably oxygenatedbottom water (Widmark and Speijer, 1997a,b; Widmark, 2000;Alegret et al., 2001). Similarly, Late Cretaceous Gyroidinoides speciesare typical to abyssal depths and also regarded as shallow infaunaltaxa that thrived under mesotrophic conditions with very little or notolerance for oxygen-poor environments (Coccioni and Galeotti,1994; Erbacher et al., 1998; Alegret et al., 2001; Alegret and Thomas,2005; Friedrich et al., 2005). The modern analogs of this genus andother small biconvex trochospiral taxa, have been found to thriveduring pre- and post-sapropel events in the Mediterranean (Jorissen,1999a; Schmiedl et al., 2003). These species are thought to have hadan opportunistic life strategy that allowed them to rapidly colonizethe re-oxygenated sediment following seafloor anoxia duringsapropel events. It may therefore be inferred that the abruptappearances of the deep sea Gyroidinoides species at the lower–middle parts of the OSM (36–37 m; Fig. 5) reflect a significantincrease in bottom water aeration while food supply remainedrelatively high and possibly a further step of seafloor deepening.

The paleoecological characteristics of Gavelinella are less certain. Ithas been shown that gavelinellids are epifaunal taxa that are fairlycommon in aerobic, oligotrophic environments (Coccioni andGaleotti, 1994; Erbacher et al., 1998; Leckie et al., 1998; Friedrichand Hemleben, 2007). Widmark and Speijer (1997a,b) argued thatthe association of gavelinellids with N20% infaunal species, isindicative of conditions of high food influx. Koutsoukos et al.(1990) described gavelinellids as epifaunal species that are typicalcomponents of dysoxic environments from the latest Cenomanian toearly Turonian of Brazil and England. Within the OSM, highoccurrences (10%–40%) of Gavelinella are coincident with abundantinfaunal species, showing a clear association of this genus with highfood supply.

The widely distributed genus Sliteria (mainly Sliteria varsoviensisGawor-Biedowa) is considered an ecomarker for the epibenthic lifemode that flourished under moderate to high food fluxes (Widmarkand Speijer, 1997a,b). The prominent occurrences of this genus in themiddle part of the OSM and upwards in assemblages B-Types 3–1(7.4% in Type 3; Fig. 4, Table 5) provide further evidence for theestablishment of fairly ventilated bottom water conditions with highfood supply during deposition of the middle and upper parts of theOSM.

0

20

40

60

80

100

0 5 10 15 20

GlobigerinelloidesHeterohelix

TOC (wt.%)

Rel

ativ

e ab

unda

nce

(%)

Fig. 9. Relative abundance of the two main planktic foraminiferal groups, Globiger-inelloides (squares) and Heterohelix (diamonds) vs. TOC content.

Table3

Themainch

aracteristicsan

drelative

abun

danc

eof

theco

mmon

gene

rain

thefive

plan

ktic

foraminife

rala

ssem

blag

es(P

-Typ

e)de

fine

dby

theclus

teran

alysis.

P-Ty

peHartella

Heteroh

elix

Laeviheteroh

elix

Pseu

dogu

embe

lina

Spirop

lecta

Globigerine

lloides

Hed

bergella

Keeled

glob

otrunc

anids

Archa

eoglob

igerina

Species

rich

ness

Plan

ktic

forams./g

TOC

(wt.%

)% G/H

% P/(P

+B)

13.6

55.6

6.3

4.5

2.4

8.4

12.0

0.9

2.4

30.0

1227

.73.5

12.7

58.8

23.1

41.7

5.3

4.9

2.3

6.5

28.4

0.8

2.7

30.0

1500

.47.5

13.1

63.8

30.9

43.1

5.2

3.3

1.0

36.4

5.5

0.9

2.2

27.1

1697

.510

.345

.652

.14

1.1

27.0

5.9

1.8

0.6

50.5

10.9

0.1

0.9

21.3

522.6

15.5

65.2

19.8

50.0

9.1

0.7

0.0

0.0

87.2

3.0

0.0

0.0

4.3

53.8

2.0

90.5

17.4

104 S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

These conditions are also implied by the moderate abundancesof agglutinated species (up to 10%) in the middle part of the OSM(B-Types 1-3; Fig. 5). Kuhnt et al. (1996) have shown that undereutrophic conditions agglutinants are mostly epifaunal detritusfeeders or shallow infaunal, with total abundances typically lowerthan those found in oligotrophic environments. Almogi-Labin et al.(1990a) studied the agglutinants of the Late Cretaceous organic-rich sequence in Israel and identified a strong linkage betweenspecies composition and bottom water oxygen level. According totheir interpretation, the absence of agglutinants in the top part ofthe Phosphate Mbr and lower part of the OSM probably indicatesvery low oxygen levels at the seafloor. The agglutinants found inthe middle part of the OSM, which include Dorothia, Arenobulimina,Verneuilina and Spiroplectammina, recall assemblage III identifiedby Almogi-Labin et al. (1990a) and indicate better aeration at thewater–sediment interface.

4.4. Paleoceanographic reconstruction

The planktic and benthic foraminiferal records of the studiedsequence show similar trends (Fig. 8) corresponding closely to thepatterns one would expect to see in modern upwelling systems (e.g.,Benguela System, SW Africa; Bruchert et al., 2000; Leiter andAltenbach, 2010). In modern upwelling systems, a change fromsediments rich in Si–P–C to organic-rich carbonates implies a shiftfrom the zone of inner shelves where upwelling intensity is maximalto outer shelves where it is gradually diminishing (Bremner, 1983;Bremner and Willis, 1993; Bruchert, et al., 2000; Giraudeau et al.,2000; Monteiro et al., 2005; Edelman-Furstenberg, 2009). Thisgradient reflects spatial reduction of water column productivity anda more aerated seafloor. Similarly, the establishment of calcareousplanktonic fauna, at the phosphate/OSM transition in the Negev area,and the coincident change in the benthic foraminiferal assemblages,which indicate a shift from severely oxygen depleted seafloor(inferred b0.1 ml O2/l) to a more aerated bottom water, seem toreflect a transition from inner to outer shelf-upper slope environ-ments. This shift also marks the onset of a widespread homogeneousdeposition of Oil Shale throughout Israel, and in other parts of theLevant region (i.e. Jordan, Turkey; Abed and Amireh, 1999; Abed et al.,2005; Inan et al., 2010). It is also indicated by the presence of chert

and phosphate southwards in Egypt in this period (Baioumy and Tada,2005; Awadalla, 2009). The Phosphate succession of the DuwiFormation in Egypt spans from the early Campanian to Maastrichtian.Baioumy and Tada (2005) demonstrated that the authigenic phos-phate of the early Campanian were, in fact, reworked and redepositedseveral times as a result of eustatic transgressions in the LateCampanian and early Maastrichtian. The eustatic curves of Miller etal. (2005) and Kominz et al. (2008) indicate that the deposition of theOSM and the lower part of the Marl Member occurred during atransgressive phase that began at ~71 Ma and peaked at ~69 Ma,when sea level raised by as much as 50 m. These observations providefurther support to the notion that sea level rise has played animportant role in this development of the upwelling sequence.

Further deepening probably occurred during deposition of themiddle part of the OSM (~32 m), when rotaliids became predominantin the benthic foraminiferal assemblages, and more specifically theabundance of the deep sea Gyroidinoides overtook that of theGavelinella (Fig. 5; Table 4).

The upward changes in the P-types and B-Types coincide with adecline in TOC content (Fig. 8) and imply a gradual decrease in surfacewater productivity from highly eutrophic to mesotrophic and at thesame time a shift from a dysaerobic to a partially to fully aerobicseafloor. These trends could indicate increasing distance from theupwelling center due to further sea level rise, and an overallweakening of the high productivity regime in this area over time asa result of a climate change. The oceanic warming phase that occurredduring the early Maastrichtian at ~69.0 Ma (MacLeod and Huber.,1996; Li and Keller, 1998b; Li and Keller, 1999; Bralower et al., 2002;Frank et al., 2005; Dameron et al., 2010) is another possiblemechanism that could have lead to the weakening or even cessationof the upwelling regime. This event is characterized by a 2–4 °Ctemperature increase affecting both surface and deep water, and mayalso involve rapid, short-lived warming events in addition to thelonger-term warming phase (Dameron et al., 2010).

In spite of the similarity between the trends exhibited by the P- andB-type assemblages of the OSM, there is a distinct time lag between thetwo records, which suggests that the increase in bottomwater aerationpredates the onset of the prominent decline in surface waterproductivity. The replacement of buliminids by rotaliid dominatedassemblages (B-Types 5–4 to 3–1) occurs in themiddle part of the OSM

Table 5The main characteristic and relative abundance of the common genera in the five benthic foraminiferal assemblages (B-Type) defined by the cluster analysis vs. TOC.

B-Type Agglutinants Eouvigerina Triserialbuliminids

Bolivina Nonionella Gyroidinoides Gavelinella Sliteria Speciesrichness

Benthicforams./g

TOC(wt.%)

% B/R % P/(P+B)

1.0 6.4 10.3 9.6 7.8 2.9 33.6 13.8 7.4 32.2 611.1 5.7 31.6 66.02.0 2.2 5.3 12.8 7.3 2.6 48.2 12.1 2.9 30.5 1021.1 10.3 27.5 46.63.0 1.0 9.6 24.1 1.9 3.5 37.3 14.6 0.6 29.5 1062.2 10.3 38.3 58.74.0 0.2 0.1 42.3 1.6 0.0 16.6 28.9 0.0 16.8 2611.9 15.3 48.0 36.85.0 0.0 0.0 98.0 0.0 0.0 0.0 0.8 0.0 6.5 3368.6 4.1 99.2 12.7

Table 4Trophic regime, life habitat and depth range of the dominant benthic foraminiferal species in this study based on their occurrences in other late Cretaceous localities: 1. Widmark andSpeijer (1997a); 2. Alegret et al. (2001); 3. Friedrich and Hemleben (2007); 4. Ashckenazi-Polivoda et al. (2010); 5. Holbourn et al. (1999a, 1999b); 6. Widmark (2000); 7. Widmarkand Speijer (1997b); 8. Friedrich et al. (2005); and 9. Widmark and Malmgren (1992).

Species Food supply Oxygen level Life habitat Paleobathymetry

Eouvigerina subsculptura McNeil & Calwell High organic matter flux1,2 Reasonably oxygenated1,2 Shallow infaunal2,6,7 Upper–middle bathyal (~500 m)1,6,7

Gavelinella beccariiformis (White) Low organic matter flux1,3,a Well oxygenated3 Epifaunal6,7,8 Middle bathyal–abyssal1,7

Gavelinella pertusa (Marsson) Seasonal food-fluxes1 Well oxygenated1 Epifaunal7 Neritic–middle bathyal1

Gyroidinoides beisseli (White) High organic matter flux2 Well oxygenated2 Shallow infaunal2,8 Abyssal2,9

Nuttallides truempyi (Nuttall) Low organic matter flux1,2,3 Well oxygenated3 Epifaunal2,6 Middle bathyal–abyssal (~600 m)1,6

Praebulimina reussi (Morrow) High organic matter flux3 Reasonably oxygenated3 Infaunal8 Middle bathyal–abyssal1,7

Praebulimina prolixa (Cushman and Parker) High organic matter flux4,5 Poorly oxygenated4,5 Infaunal Outer shelf5

Reussella szajnochae (Grzybowski) Low organic matter flux3 Well oxygenated3 Epifaunal3

Sliteria varsoviensis (Gawor-Biedowa) High organic matter flux1 Reasonably oxygenated1 Epifaunal7 Upper–middle bathyal (~500 m)1,7

a Gavelinella beccariiformis was considered by Widmark and Speijer (1997a) as indicative of oligotrophic conditions unless occurring with infaunal population exceeding 20%.Nuttallides and Reussella, that represent generally low organic matter flux and well oxygenated sea floor, are absent in the studied sequence.

105S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

(~32 m). On the other hand, the change from Globigerinelloides toheterohelicid dominated assemblages (P-Types 5–4 to 3–1) occurs inthe upper part of theOSM(~25 m; Fig. 8). This pattern indicates that therelatively ventilated conditions of the bottom water were establishedduring times of relatively high surface water productivity. Theseconditions could have resulted from a regional or global sea level rise(Miller et al., 2005). Deepening may have caused a reduction in netorganic carbon flux to the seafloor and consequently an increase inventilation, with surface productivity remaining relatively high(e.g., Suess, 1980; Altenbach and Sarnthein, 1989; Loubere, 1997).

The establishment of assemblages P-Type 1 and B-Type 1 and thefurther decrease in TOC content in the upper part of theOSMandbase oftheMarlMbr (~15 m) are associatedwith a shift tomesotrophic pelagicconditions with relatively well-aerated bottomwater. These conditionspersisted in this region throughout most of the Maastrichtian, asrecently reported by Abramovich et al. (2010) based on the relativelyhigh abundance of Globigerinelloides species (up to N15%) and thevery rare occurrence (less than 1%) of racemiguembelinids, whichare regarded as photosymbiotic species thriving in oligotrophicenvironments.

5. Conclusions

1. The accumulation in the Southern Tethys in the Negev region ofIsrael of a 40-m-thick sequence rich in organic carbon andcontaining a unique Late Cretaceous foraminiferal assemblage ismainly attributable to the influence of a dynamic upwellingsystem. A comparison between the planktic and benthic forami-niferal records during the last phase of this long-lasting upwellingsystem enabled objective evaluation of the paleoenvironmentalchanges in the upper water column and at the seafloor.

2. Our new planktic foraminiferal biostratigraphy scheme wascompiled by integrating primary and secondary planktic forami-niferal data with occurrences of calcareous nannofossils andinoceramid bivalves. It was deduced from this scheme that theentire oil shale sequence spans a maximum of 1.85 m.y. from 71.6to 69.85 Ma, for a minimum sedimentation rate of 2.4 cm/kyr.

3. Five distinct planktic foraminiferal assemblages (P-Types) weredistinguished in the studied sequence. The changes in theassemblages along the section are correlated with variations inTOC content, signifying a strong linkage between plankticforaminiferal assemblages and different degrees of surface waterproductivity. In particular, using this correlation it is inferred thatthe Globigerinelloides (mainly Globigerinelloides asper) constitutethe best tracers for extreme levels of surface water productivity(eutrophic conditions), whereas heterohelicids are associated withmore mesotrophic conditions.

4. Changes in bottom water aeration were determined based on fivedistinct benthic foraminiferal assemblages (B-Types 5–1). Theupward gradient from assemblages B-Type 5 to B-Type 1 is chieflyexpressed in a transition from triserial buliminid assemblages tomore diversified rotaliid dominated assemblages. This transitiontestifies to an increase in bottom water aeration and perhapsdeepening during the prevalence of the Southern Tethys upwellingsystem.

5. The correspondence between the trends exhibited by the B-Typeand P-Type assemblages and the TOC contents determined alongthe study sequence implies a strong linkage between changes insurface water productivity and bottom water aeration. Based onthis relationship and the foraminiferal records, we were able toinfer a decline in surface water productivity from eutrophic tomesotrophic conditions and an increase in bottom water aerationbeginning from the top of the Phosphate Mbr and continuingupwards through the OSM section and up to the base of the MarlMbr. Themesotrophic conditions established at the end of the OSMlasted until the last part of the Maastrichtian.

6. The transition from the Phosphate Mbr to the OSM marks majorchange in the evolution of this high-productivity regime, thatinvolved reorganization of the marine ecosystem and a significantdecrease in the upper water fertility as a result of a regional sealevel rise and southward migration of the upwelling zone at thattime. The transition to the Marl Member marks weakening of theupwelling system as a result of greenhouse warming and sea levelrise and the establishment of mesotrophic condition.

Acknowledgments

We wish to express our gratitude to S. Volin from Rotem AmfertNegev Company for his cooperation, to S. Kronenblum and M. Salmonfor their assistance in field work, and to M. Kitin from the GeologicalSurvey of Israel and I. Gefen fromBen-GurionUniversity of theNegev fortheir assistance in the laboratory procedures. We greatly thank R. MarkLeckie and the anonymous reviewer for their contribution towardimprovement of this paper. The research was supported by GIF – TheGerman-Israeli Foundation for Scientific Research and Development –grant no. 956-38.8/2007 and by Israeli Ministry of Infrastructure grantno. 27-17-005.

References

Abed, A.M., Amireh, B.S., 1999. Sedimentology, geochemistry, economic potential andpalaeogeography of an Upper Cretaceous phosphorite belt in the southeasterndesert of Jordan. Cretaceous Research 20, 119–130.

Abed, A.M., Arouri, K.R., Boreham, C.J., 2005. Source rock potential of the phosphoritebituminous chalk–marl sequence in Jordan.Marine andPetroleumGeology 22, 413–425.

Abramovich, S., Keller, G., 2002. High stress late Maastrichtian paleoenvironment:inference from planktonic foraminifera in Tunisia. Palaeogeography, Palaeoclima-tology, Palaeoecology 178, 145–164.

Abramovich, S., Keller, G., 2003. Planktonic foraminiferal response to the latestMaastrichtian abrupt warm event: a case study from South Atlantic DSDP Site525A. Marine Micropaleontology 48, 225–249.

Abramovich, S., Almogi-Labin, A., Benjamini, C., 1998. Decline of Maastrichtian pelagicecosystem based on planktic foraminiferal assemblage changes: implications forthe terminal Cretaceous faunal crisis. Geology 26, 63–66.

Abramovich, S., Keller, G., Stuben, D., Berner, Z., 2003. Characterization of lateCampanian and Maastrichtian planktic foraminiferal depth habitats and vitalactivities based on stable isotopes. Palaeogeography, Palaeoclimatology, Palaeoe-cology 202, 1–29.

Abramovich, S., Yovel-Corem, S., Almogi-Labin, A., Benjamini, C., 2010. Global climatechange and planktic foraminiferal response in the Maastrichtian. Paleoceanogra-phy 25, PA2201. doi:10.1029/2009PA001843.

Alegret, L., Thomas, E., 2001. Upper Cretaceous and lower Paleogene benthicForaminifera from northeastern Mexico. Micropaleontology 47, 269–316.

Alegret, L., Thomas, E., 2005. Cretaceous/Paleogene boundary bathyal paleo-environ-ments in the central North Pacific (DSDP Site 465), the Northwestern Atlantic (ODPSite 1049), the Gulf of Mexico and the Tethys: the benthic foraminiferal record.Palaeogeography, Palaeoclimatology, Palaeoecology 224, 53–82.

Alegret, L., Thomas, E., 2009. Food supply to the seafloor in the Pacific Ocean after theCretaceous/Paleogene boundary event. Marine Micropaleontology 73, 105–116.

Alegret, L., Molina, E., Thomas, E., 2001. Benthic foraminifera at the Cretaceous–Tertiaryboundary around the Gulf of Mexico. Geology 29, 891–894.

Almogi-Labin, A., Bein, A., Sass, E., 1990a. Agglutinated foraminifera in organic-richneritic carbonates (Upper Cretaceous, Israel) and their use in identifying oxygenlevels in oxygen-poor environments. In: Hemleben, C., Kaminski, M.A., Kuhnt, W.,Scott, D.B. (Eds.), Paleoecology, Biostratigraphy, Paleoceanography and Taxonomyof Agglutinated Foraminifera. Kluwer Academic Publishers, pp. 565–585.

Almogi-Labin, A., Flexer, A., Honigstein, A., Rosenfeld, A., Rosenthal, E., 1990b.Biostratigraphy and tectonically controlled sedimentation of the Maastrichtian inIsrael and adjacent countries. Revista Espanola De Paleontologia 5, 41–52.

Almogi-Labin, A., Bein, A., Sass, E., 1993. Late Cretaceous upwelling system along thesouthern Tethys margin (Israel): interrelationship between productivity, bottomwater environments and organic matter preservation. Paleoceanography 8, 671–690.

Altenbach, A., Sarnthein, M., 1989. Productivity record in Benthic Foraminifera. In:Berger, W., Smetacek, V., Wefer, G. (Eds.), Productivity of the Ocean: Present andPast. Wiley, New York, pp. 255–270.

Ashckenazi-Polivoda, S., Edelman-Furstenberg, Y., Almogi-Labin, A., Benjamini, C.,2010. Characterization of lowest oxygen environments within ancient upwellingenvironments: benthic foraminifera assemblages. Palaeogeography, Palaeoclima-tology, Palaeoecology 289, 134–144.

Awadalla, G.M., 2009. Geochemistry and microprobe investigations of Abu Tartur REE-bearing phosphorite, Western Desert, Egypt. Journal of African Earth Sciences 57,431–443.

Baioumy, H., Tada, R., 2005. Origin of late Cretaceous phosphorites in Egypt. CretaceousResearch 26, 261–275.

106 S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

Barrera, E., Keller, G., 1990. Stable isotope evidence for gradual environmental changesand species survivorship across the Cretaceous/Tertiary boundary. Paleoceano-graphy 5, 867–890.

Bein, A., Amit, O., 1982. Depositional-environments of the Senonian chert, phosphoriteand oil-shale sequence in Israel as deduced from their organic-matter composition.Sedimentology 29, 81–90.

Bein, A., Almogi-Labin, A., Sass, E., 1990. Sulfur sinks and organic–carbon relationshipsin Cretaceous organic-rich carbonates—implications for evaluation of oxygen-poordepositional-environments. American Journal of Science 290, 882–911.

Bernhard, J.M., 1986. Characteristic assemblages and morphologies of benthicforaminifera from anoxic, organic-rich deposits: Jurassic through Holocene. Journalof Foraminiferal Research 16, 207–215.

Bernhard, J.M., 1996.Microaerophilic and facultative anaerobic benthic foraminifera: a reviewof experimental and ultrastructural evidence. Revue de Paléobiologie 15, 261–275.

Bernhard, J.M., Sen Gupta, B.K., 1999. Foraminifera of oxygen depleted environments.In: Sen Gupta, B.K. (Ed.), Modern Foraminifera: Dordrecht. Kluwer AcademicPublishers, The Netherlands, pp. 201–216.

Bernhard, J.M., Sen Gupta, B.K., Borne, P.F., 1997. Benthic foraminiferal proxy toestimate dysoxic bottom-water oxygen concentration: Santa Barbara Basin, U.S.Pacific continental margin. Journal of Foraminiferal Research 27, 301–310.

Bralower, T.J., Premoli Silva, I., Malone, M.J., 2002. New evidence for abrupt climatechange in the Cretaceous and Paleogene; an Ocean Drilling Program expedition toShatsky Rise, Northwest Pacific. GSA Today 12, 4–10.

Bremner, J.M., 1983. Biogenic sediments on the South West African (Namibian)continental margin. In: Thiede, J., Suess, E. (Eds.), Coastal Upwelling, Its SedimentRecords; Part B, Sedimentary Records of Ancient Coastal Upwelling: NATOConference Series IV, Marine Sciences, 10b, pp. 73–104.

Bremner, J.M., Willis, P.C., 1993. Mineralogy and geochemistry of the clay fraction ofsediments from the Namibian continental margin and the adjacent hinterland.Marine Geology 115, 85–116.

Bruchert, V., Perez, M.E., Lange, C.B., 2000. Coupled primary production, benthicforaminiferal assemblage, and sulfur diagenesis in organic-rich sediments of theBenguela upwelling system. Marine Geology 163, 27–40.

Caron, M., Homewood, P., 1983. Evolution of early planktic foraminifera. MarineMicropaleontology 7, 453–462.

Coccioni, R., Galeotti, S., 1994. K–T boundary extinction: geologically instantaneous orgradual event? Evidence from deep-sea benthic foraminifera. Geology 22, 779–782.

Conan, S.M.H., Brummer, G.J.A., 2000. Fluxes of planktic foraminifera in response tomonsoonal upwelling on the Somalia Basin margin. Deep Sea Research Part-II 47,2207–2227.

Dameron, S., Leckie, R.M., Clark, K.R., Frank, T.D., Schroeder, E., 2010. Benthicforaminiferal population and isotope changes at the mid-Maastrichtian event,Shatsky Rise, North Pacific. Geol. Soc. Amer. Abstracts with Program.

D'Hondt, S., Arthur, M.A., 1995. Interspecies variation in stable isotopic signals ofMaastrichtian planktonic foraminifera. Paleoceanography 10, 123–135.

Edelman-Furstenberg, Y., 2009. Cyclic upwelling facies along the Late Cretaceoussouthern Tethys (Israel): taphonomic and ichnofacies evidence of a high-productivity mosaic. Cretaceous Research 30, 847–863.

Erbacher, J., Gerth, W., Schmiedl, G., Hemleben, C., 1998. Benthic foraminiferalassemblages of late Aptian–early Albian black shale intervals from the VocontianBasin, SE France. Cretaceous Research 19, 805–826.

Eshet, Y., Almogi-Labin, A., 1996. Calcareous nannofossils as paleoproductivity indicatorsin Upper Cretaceous organic-rich sequences in Israel. Marine Micropaleontology 29,37–61.

Eshet, Y., Almogi-Labin, A., Bein, A., 1994. Dinoflagellate cysts, paleoproductivity andupwelling systems: a Late Cretaceous example from Israel. Marine Micropaleon-tology 23, 231–240.

Fiorentino, A., 1995. Calcareous nannofossil stratigraphy of Maastrichtian sections inIsrael. Cretaceous Research 16, 327–341.

Flexer, A., 1968. Stratigraphy and facies development of Mount Scopus Group(Senonian–Paleocene) in Israel and adjacent countries. Israel Journal of EarthSciences 17, 85–114.

Frank, T.D., Thomas, D.J.R., Leckie, R.M., Arthur, M.A., Bown, P.R., Jones, K., Lees, J.A.,2005. The Maastrichtian record from Shatsky Rise (northwest Pacific): a tropicalperspective on global ecological and oceanographic changes. Paleoceanography 20,PA1008. doi:10.1029/2004PA001052.

Friedrich, O., 2009. Benthic foraminifera and their role to decipher paleoenvironmentduring mid-Cretaceous Oceanic Anoxic Events—the “anoxic benthic foraminifera”paradox. Revue de Micropaléontologie 53, 175–192.

Friedrich, O., Hemleben, C., 2007. Early Maastrichtian benthic foraminiferal assem-blages from the western North Atlantic (Blake Nose) and their relation topaleoenvironmental changes. Marine Micropaleontology 62, 31–44.

Friedrich, O., Hemleben, C., Herrle, J.O., 2005. Climatic changes in the Late Campanian–Early Maastrichtian: micropaleontology and stable isotopic evidence from anepicontinental sea. Journal of Foraminiferal Research 35, 228–247.

Friedrich, O., Schmiedl, G., Erlenkeuser, H., 2006. Stable isotope composition of LateCretaceous benthic foraminifera from the southern South Atlantic: biological andenvironmental effects. Marine Micropaleontology 58, 135–157.

Giraudeau, J., Bailey, G.W., Pujol, C., 2000. A high-resolution time series analyses ofparticle fluxes in the Northern Benguela coastal upwelling system: carbonaterecord of changes in biogenic production and particle transfer processes. Deep-SeaResearch II 47, 1999–2028.

Gooday, A.J., 2003. Benthic foraminifera (Protista) as tools in deep-water palaeoceano-graphy: environmental influences on faunal characteristics. In: Southward, A.J.,Tyler, P.A., Young, C.M., Fuiman, L.A. (Eds.), Advances in Marine Biology, 46.Academic Press, London, UK, pp. 3–90.

Gradstein, F.M., et al., 1994. A Mesozoic time-scale. Journal of Geophysical Research-Solid Earth 99 (b12), 24051–24074.

Gradstein, F.M., Ogg, J.G., Smith, A.G. (Eds.), 2005. A Geologic Time Scale 2004.Cambridge University Press. 610 pp.

Haq, B.U., Hardenbol, J., Vail, P.R., 1987. Chronology of fluctuating sea levels since theTriassic. Science 235, 1156–1167.

Hart, M.B., 1980. A water depth model for evolution of the planktonic foraminifera.Nature 286, 252–254.

Hemleben, C., Spindler, M., Anderson, O.R., 1989. Modern Planktonic Foraminifera.Springer Verlag. 363 pp.

Holbourn, A., Kuhnt, W., El Albani, A., Ly, A., Gomez, R., Herbin, J.P., 1999a.Palaeoenvironments and palaeobiogeography of the Late Cretaceous Casamancetransect (Senegal, NW Africa): distribution patterns of benthic foraminifera,organic carbon and terrigenous flux. Neues Jahrbuch für Geologie und Paläonto-logie Abhandlungen 21, 335–377.

Holbourn, A., Kuhnt, W., El Albani, A., Pletsch, T., Luderer, F., Wagner, T., 1999b. UpperCretaceous palaeoenvironments and benthonic foraminiferal assemblages ofpotential source rocks from the western African margin, Central Atlantic. In:Cameron, N.R., Bate, R.H., Clure, V.S. (Eds.), The Oil and Gas Habitats of the SouthAtlantic: Geological Society, London, Special Publications, 153, pp. 195–222.

Holbourn, A., Kuhnt, W., Erbacher, J., 2001. Benthic foraminifera from lower Albianblack shales (site 1049, ODP leg 171): evidence for a non “uniformitarian” record.Journal of Foraminiferal Research 31, 60–74.

Huber, B.T., MacLeod, K.G., Tur, N.A., 2008. Chronostratigraphic framework for upperCampanian–Maastrichtian sediments on the Blake Nose (subtropical NorthAtlantic). Journal of Foraminiferal Research 38, 162–182.

Inan, S., Ugur, F.A., Inan, T., Yalcin, M.N., Mann, U., 2010. Relationship between organicmatter, sulphur and phosphate contents in Upper Cretaceous marine carbonates(Karabogaz Formation, SE Turkey): implications for early oil generation. Journal ofPetroleum Geology 34, 319–337.

Jorissen, F.J., 1999a. Benthic foraminiferal successions across Late QuaternaryMediterranean sapropels. Marine Geology 153, 91–101.

Jorissen, F.J., 1999b. Benthic foraminiferal microhabitats below the sediment–waterinterface. In: Sen Gupta, B.K. (Ed.), Modern Foraminifera: Dordrecht. KluwerAcademic Publishers, The Netherlands, pp. 161–179.

Jorissen, F.J., de Stigter, H.C., Widmark, G.V., 1995. A conceptual model explainingbenthic foraminiferal microhabitats. Marine Micropaleontology 26, 3–16.

Kaiho, K., 1994. Benthic foraminiferal dissolved-oxygen index and dissolved-oxygenlevels in modern ocean. Geology 22, 719–722.

Keller, G., Pardo, A., 2004. Disaster opportunists Guembelitrinidae: index forenvironmental catastrophes. Marine Micropaleontology 53, 83–116.

Kolodny, Y., 1980. Carbon isotopes and depositional environment of a high productivitysedimentary sequence—the case of the Mishash-Ghareb Formations, Israel. IsraelJournal of Earth Sciences 29, 147–156.

Kolodny, Y., Garrison, R.E., 1994. Sedimentation and diagenesis in paleo-upwellingzones of epeiric sea and basinal settings: a comparison of the Cretaceous MishashFormation of Israel and the Miocene Monterey Formation of California. Proc. 29thInternational Geological Congress part C, pp. 133–158.

Kominz, M.A., Browning, J.V., Miller, K.G., Sugarman, P.J., Mizintsevaw, S., Scotese, C.R.,2008. Late Cretaceous to Miocene sea-level estimates from the New Jersey andDelaware coastal plain coreholes: an error analysis. Basin Research 20, 211–226.

Koutsoukos, E.A.M., Leary, P.M., Hart, M.B., 1990. Latest Cenomanian–earliest Turonianlow-oxygen tolerant benthonic foraminifera: a case study from the Sergipe Basin(N.E. Brazil) and the western Anglo-Paris Basin (southern England). Palaeogeo-graphy, Palaeoclimatology, Palaeoecology 77, 145–177.

Krenkel, E., 1924. Der Syrische Bogen. Zentralblatt für Mineralogie, Geologie undPaläontologie, Abhandlungen, B 9, 274–281 and 10, 301–313.

Kroon, D., Nederbragt, A.J., 1990. Ecology and paleoecology of triserial plankticforaminifera. Marine Micropaleontology 16, 25–38.

Kuhnt, W., Moullade, M., Kaminski, M.A., 1996. Ecological structuring and evolution ofdeep sea agglutinated foraminifera—a review. Revue de Micropaléontologie 39,271–282.

Leckie, R.M., 1987. Paleoecology of mid-Cretaceous planktonic foraminifera: acomparison of open ocean and Epicontinental Sea assemblages. Micropaleontology33, 164–176.

Leckie, R.M., Olson, H.C., 2003. Foraminifera as proxies for sea-level change onsiliciclastic margins. In: Leckie, R.M., Olson, H.C. (Eds.), Micropaleontologic Proxiesfor Sea-level Change and Stratigraphic Discontinuities: Society for SedimentaryGeology Special Publication, 75, pp. 5–19.

Leckie, R.M., Yuretich, R.F., West, O.L.O., Finkelstein, D., Schmidt, M., 1998. Paleoceano-graphy of the southwestern Western Interior Sea during the time of theCenomanian–Turonian boundary (Late Cretaceous). Society for SedimentaryGeology, Concepts in Sedimentology and Paleontology 6, 101–126.

Leiter, C., Altenbach, A.V., 2010. Benthic Foraminifera from the diatomaceous Mud Beltoff Namibia: characteristic species for severe anoxia. Paleontologia Electronica 13,13.2.11A.

Leutenegger, S., Hansen, H.J.R., 1979. Ultrastructural and radiotracer studies of porefunction in foraminifera. Marine Biology 54, 11–16.

Li, L., Keller, G., 1998a. Diversification and extinction in Campanian–Maastrichtianplanktic foraminifera of Northwestern Tunisia. Eclogea Geolgicae Helvetiae 91,75–102.

Li, L., Keller, G., 1998b. Maastrichtian climate, productivity and faunal turnovers inplanktic foraminifera in South Atlantic DSDP sites 525A and 21. MarineMicropaleontology 33, 55–86.

Li, L., Keller, G., 1999. Variability in Late Cretaceous climate and deep waters: evidencefrom stable isotopes. Marine Micropaleontology 161, 171–190.

107S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108

Author's personal copy

Loubere, P., 1997. Benthic foraminiferal assemblage formation, organic carbon flux andoxygen concentrations on the outer continental shelf and slope. Journal ofForaminiferal Research 27, 93–100.

Loubere, P., Fariduddin, M., 1999. Benthic foraminifera and the flux of organic carbon tothe seabed. In: Sen Gupta, B.K. (Ed.), Modern Foraminifera: Dordrecht. KluwerAcademic Publishers, The Netherlands, pp. 181–199.

Luz, B., Reiss, Z., 1983. Stable carbon isotopes in Quaternary foraminifera from the Gulfof Aqaba (Elat) Red Sea. Utrecht Micropalaeontological Bulletins 30, 129–140.

MacLeod, K.G., 1994a. Bioturbation, inoceramid extinction, and Mid-Maastrichtianecological change. Geology 22, 139–142.

MacLeod, K.G., 1994b. Extinction of Inoceramid bivalves in Maastrichtian strata of theBay of Biscay region of France and Spain. Journal of Paleontology 68, 1048–1066.

MacLeod, K.G., Huber, B.T., 1996. Reorganization of deep ocean circulation accompa-nying a Late Cretaceous extinction event. Nature 380, 422–425.

Miller, K.G., Kominz, M.A., Browning, J.V., Wright, J.D., Mountain, G.S., Katz, M.E.,Sugarman, P.J., Cramer, B.S., Christie-Blick, N., Pekar, S.F., 2005. The Phanerozoicrecord of global sea-level change. Science 310, 1293–1298.

Minster, T., 1996. Basin reconstruction in the Senonian sequence, northern Negev—acontribution to the understanding of anoxic events. Ph.D. thesis, Tel-AvivUniversity, Israel, 285 pp.

Mohtadi, M., Hebbeln, D., Marchant, M., 2005. Upwelling and productivity along thePeru–Chile Current derived from faunal and isotopic compositions of plankticforaminifera in surface sediments. Marine Geology 216, 107–126.

Monteiro, P.M.S., van der Nelson, G., Plas, A., Mabille, E., Bailey, G.W., Klingelhoeffer, E.,2005. Internal tide–shelf topography interactions as a forcing factor governing thelarge-scale distribution and burial fluxes of particulate organic matter (POM) in theBenguela upwelling system. Continental Shelf Research 25, 1864–1876.

Nyong, E.E., Olsson, R.K., 1984. A paleoslope model of Campanian to LowerMaastrichtian foraminifera in the North American Basin and adjacent continentalmargin. Marine Micropaleontology 8, 437–477.

Odin, G.S., Lamaurelle, M.A., 2001. The global Campanian–Maastrichtian stageboundary. Episode 24, 229–238.

Pardo, A., Keller, G., 2008. Biotic effects of environmental catastrophes at the end of theCretaceous and early Tertiary: Guembelitria and Heterohelix blooms. CretaceousResearch 29, 1058–1073.

Parrish, J.T., 1998. Interpreting Pre-Quaternary Climate from the Geologic Record.Columbia University Press. 338 pp.

Parrish, J.T., Curtis, R.L., 1982. Atmospheric circulation, upwelling, and organic-richrocks in the Mesozoic and Cenozoic eras. Palaeogeography, Palaeoclimatology,Palaeoecology 40, 31–66.

Reiss, Z., 1962. Stratigraphy of phosphate deposits in Israel. Israel Geological SurveyBulletin 34, 1–23.

Reiss, Z., 1988. Assemblages from a Senonian high-productivity sea. Revue dePaleobiologie, Special Volume 2, 323–332.

Reiss, Z., Almogi-Labin, A., Honigstein, A., Lewy, Z., Lipson-Benitah, S., Moskovitz, S.,Zaks, Y., 1985. Late Cretaceous multiple stratigraphic framework of Israel. IsraelJournal of Earth Sciences 34, 147–166.

Robaszynski, F., Caron, M., Gonzales Donoso, J.M., Wonders, A.A.H., 1984. Atlas of LateCretaceous globotruncanids. Revue de Micropaléontologie 26, 145–305.

Schiebel, R., Hemleben, C., 2000. Interannual variability of planktic foraminiferalpopulations and test flux in the eastern North Atlantic Ocean (JGOFS). Deep-SeaResearch II 47, 1809–1852.

Schiebel, R., Zeltner, A., Treppke, U.F., Waniek, J.J., Bollmann, J., Rixen, T., Hemleben, C.,2004. Distribution of diatoms, coccolithophores and planktic foraminifers along atrophic gradient during SW monsoon in the Arabian Sea. Marine Micropaleontol-ogy 51, 345–371.

Schmiedl, G., Mitschele, A., Beck, S., Emeis, K.-C., Hemleben, C., Schulz, H., Sperling, M.,Weldeab, S., 2003. Benthic foraminiferal record of ecosystem variability in theeastern Mediterranean Sea during times of sapropel S5 and S6 deposition.Palaeogeography, Palaeoclimatology, Palaeoecology 190, 139–164.

Schneider-Mor, A., Ashckenazi-Polivoda, S., Feinstein, S., Almogi-Labin, A., Abramovich,S., in preparation. Paleoceanographic reconstruction of the Late Cretaceous oil shaleof the Negev, Israel: integration of foraminiferal, TOC and stable isotope records.

Sen Gupta, B.K., Machain-Castillo, M.L., 1993. Benthic foraminifera in oxygen-poorhabitats. Marine Micropaleontology 20, 183–201.

Shahar, Y., Wurzburger, U., 1967. A new oil shale deposit in the Northern Negev,Israel. The Proceedings of the Seventh World Petroleum Congress, 3. Elsevier,London, pp. 719–728.

Shannon, L.V., 1985. The Benguela ecosystem Part 1. Evolution of the Benguela, physicalfeatures and processes. Oceanography and Marine Biology. Annual Review 23,105–182.

Soudry, D., Nathan, Y., Roded, R., 1985. The Ashosh-Haroz facies and their significancefor the Mishash palaeogeography and phosphorite accumulation in northern andcentral Negev, southern Israel. Israel Journal of Earth Sciences 34, 211–220.

Soudry, D., Glenn, C.R., Nathan, Y., Segal, I., VonderHaar, D., 2006. Evolution of Tethyanphosphogenesis along the northern edges of the Arabian–African shield during theCretaceous–Eocene as deduced from temporal variations of Ca and Nd isotopes andrates of P accumulation. Earth Science Reviews 78, 27–57.

Suess, E., 1980. Particulate organic carbon flux in the oceans—surface productivity andoxygen utilization. Nature 288, 260–263.

Suess, E., Thiede, J. (Eds.), 1983. Coastal Upwelling, Its Sediment records; Part A,Responses of the Sedimentary Regime to Present Coastal Upwelling: NATOConference Series IV, Marine Sciences, 10a. 604 pp.

Summerhayes, C.P., Prell, W.L., Emeis, K.C., 1992. Evolution of upwelling system sincethe Early Miocene. In: Summerhayes, C.P., Prell, W.L., Emeis, K.C. (Eds.), UpwellingSystem: Evolution of Upwelling System since the Early Miocene: Geological SocietySpecial Publication, 64, pp. 1–5.

Thiede, J., Suess, E. (Eds.), 1983. Coastal Upwelling, Its Sediment Records; Part B,Sedimentary Records of Ancient Coastal Upwelling: NATO Conference Series IV,Marine Sciences, 10b. 610 pp.

Widmark, J.G.V., 2000. Biogeography of terminal Cretaceous benthic foraminifera:deep-water circulation and trophic gradients in the deep South Atlantic. CretaceousResearch 21, 367–379.

Widmark, J.G.V., Malmgren, B.A., 1992. Biogeography of terminal Cretaceous deep-seabenthic foraminifera from the Atlantic and Pacific Oceans. Palaeogeography,Palaeoclimatology, Palaeoecology 92, 375–405.

Widmark, J.G.V., Speijer, R.P., 1997a. Benthic foraminiferal ecomarker species of theterminal Cretaceous (late Maastrichtian) deep-sea Tethys. Marine Micropaleon-tology 31, 135–155.

Widmark, J.G.V., Speijer, R.P., 1997b. Benthic foraminiferal faunas and trophic regimesof the terminal Cretaceous Tethyan seafloor. Palaios 12, 354–371.

108 S. Ashckenazi-Polivoda et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 305 (2011) 93–108