Growth and crises of the Late Albian - Turonian carbonate platform, west central Jordan: integrated stratigraphy and environmental changes

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(1)Growth and crises of the Late Albian - Turonian carbonate platform, west central Jordan: integrated stratigraphy and environmental changes. Dissertation zur Erlangung des Doktorgrades der Naturwissenschaften Fachbereich Geowissenschaften Universität Bremen. vorgelegt von Frauke Schulze Bremen, 2003.

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(3) Preface. Preface The present thesis includes three papers, which are either submitted or published. Titles, co-authors and own contributions to the single articles are as follows. Chapter 2 F. Schulze, Z. Lewy, J. Kuss and A. Gharaibeh (2003) Cenomanian-Turonian carbonate platform deposits in west central Jordan. International Journal of Earth Sciences, 92 (4): 641-660; published Own contributions: field work, preparation and investigation of marl and clay samples, investigation of thin sections (limestone samples), extraction of microfossils and determination of benthic and planktic foraminifers, interpretation and correlation of lithology, biostratigraphy and sequence stratigraphy, review and incorporation of published data into the presented models and schemes, text and figures. Chapter 3 The upper Albian to Turonian carbonate platform succession of west central Jordan stratigraphy and crises. F. Schulze, A. Marzouk, M. A. Bassiouni, J. Kuss; Cretaceous Research, submitted Own contributions: field work, preparation and investigation of marl and clay samples, extraction of microfossils and determination of benthic and planktic foraminifers, investigation of thin sections, ecological interpretations (foraminifers, ostracodes),. integrated. stratigraphical. correlation. and. paleoceanographic. interpretations, comparisons with published data, text and figures (except photomicrographs of calcareous nannofossils). Chapter 4 Platform configuration, microfacies and cyclicities of the upper Albian to Turonian of west central Jordan. F. Schulze, J. Kuss and A. Marzouk; Facies, submitted Own contributions: field work, all microfacies and facies data, development of facies models, sedimentological investigation and statistical analyses of higher-frequent cyclicities. (accommodation. plots),. paleogeographical. reconstructions. and. comparisons with published data, text and figures. I.

(4) Preface. All data sets of this thesis are kept at Bremen University, Department of Geosciences (Geochronology, Group of Prof. Dr. J. Kuss). Additionally, all rock and soft samples, most macrofossils, washing residues, extracted microfossils and all thin sections are stored at Bremen University. Smear slides for calcareous nannofossils are archived by Dr. A. M. Marzouk, University of Tanta, Geology Department/Faculty of Science in Cairo/Egypt. Ammonites are partly stored by Prof. Dr. Z. Lewy, Geological Survey of Israel in Jerusalem/Israel. Summary The depositional evolution and architecture of upper Albian to Turonian carbonate platforms of today’s west central Jordan are reconstructed within this thesis. Therefore, global controlling factors (eustatic sea-level fluctuations, productivity events, orbital forcing) and regional factors (tectonics, paleogeography, faunal and floral associations of the inner shelf) on platform development are considered. Furthermore, platform evolution and deposits of the study area are compared and discussed with time equivalent, published data of neighbouring areas on the Arabian plate and in the Tethyan realm. The results of sedimentologic, biostratigraphic and facies investigations on washing samples, thin sections and macrofossils, as well as from quantitative analyses of higher-frequent carbonate cycles (accommodation cycles) are presented in three single articles, which are either published (Chapter 2) or submitted to international journals (Chapter 3, 4). CHAPTER 2 contains an integrated correlation of lithologic and multibiostratigraphic data, which constitute the basis for a newly established sequence stratigraphic scheme. This model contains eight sedimentary sequences and seven sequence boundaries and it provides a large-scale north to south correlation on the platform. This correlation shows that the late Cenomanian ‘Karak Limestone Member’ is the southern stratigraphic equivalent of the Hummar Limestone Formation in the north. Furthermore, the new scheme is compared with global models and regional sequence stratigraphic schemes from Israel and Sinai. Based on these comparisons, both transgressions during early Cenomanian and late Turonian times that are accompanied by a prograding and an aggrading of the carbonate platform, as well as the platform drowning during the uppermost Cenomanian to the lower Turonian are assumed to be eustatically driven. The same is assumed for a major sea-level II.

(5) Preface. lowstand, reflected by middle Turonian successions. In contrast, additional or missing sequence boundaries are interpreted to be predominantly a result from minor order sea-level variations or are related to synsedimentary regional tectonics. Increased subsidence in the central study area is assumed for middle Cenomanian to middle Turonian times. In CHAPTER 3 a multibiostratigraphic scheme supports a detailed stratigraphy, where the biostratigraphy is mainly based on ammonites and calcareous nannofossils, supplemented by foraminifers and ostracodes. Ammonite occurrences, which cover the mantelli to woollgari biozones facilitate a precise subdivision of lower Cenomanian to middle Turonian deposits. Furthermore, three ammonite bearing marker horizons provide a large-scaled correlation of uppermost Cenomanian to middle Turonian successions. Additionally, five benthic foraminifer assemblages and two ostracode associations are established as well as five units that base on these new stratigraphic and paleoecologic data, are defined and allow long-range correlations. Moreover, a subdivision of the platform evolution into three phases of platform growth and two main phases of platform crises is possible. The first crisis is observed in the central study area during middle Cenomanian times, while the second crises affected the entire platform within the Cenomanian/Turonian-boundary interval. Both events are highlighted by deeper water and locally dysoxic conditions. This oxygen depleted facies shifted southwards during late Cenomanian times and re-appears in the central area during early Turonian times. In CHAPTER 4 fifteen microfacies types and eight areas of deposition are defined and combined to form a facies scheme, which provides correlation of spatial and temporal paleo-environmental changes on the shelf. Furthermore, an integration of this facies scheme into the sequence stratigraphic framework (Chapter 2) makes it possible to reconstruct paleogeographic conditions on the shelf and to compare them with those of adjacent shelf areas in Israel and Egypt. This suggests increased subsidence for the central study area, where it locally (area of Wadi Al Karak) persists from the middle Cenomanian to middle Turonian times. Subsidence occurs also in the south during upper Cenomanian to lower Turonian times. Inversion is postulated for the same time interval in the area of Wadi Mujib in central Jordan. Similar basin structures and ‘paleo-highs’ coevally occur in western adjacent areas III.

(6) Preface. (Israel and Sinai). Deeper water dysoxic deposits are linked to the basin structures in the central and southern area. Statistical analyses of rhythmic bedded carbonates exhibit accommodation changes and higher-frequent cyclicities that are interpreted to be partly driven by autocyclic mechanisms, but predominantly by allocyclic factors (mainly eustasy). These accommodation patterns are integrated into the existing sequence stratigraphic scheme (Chapter 2) and partly correlate with the appropriate sedimentary sequences and boundaries.. Zusammenfassung Die. Ablagerungsgeschichte. und. Architektur. der. Oberalb. bis. Turon. Karbonatplattformen des heutigen West-Zentral Jordaniens werden im Rahmen dieser Arbeit rekonstruiert. Dabei wurden globale Steuerungsfaktoren (eustatische Meeresspiegeländerungen, Produktivitätsereignisse, orbitale Kräfte) und regionale Faktoren (Tektonik, Paläogeographie, faunale und florale Assoziationen auf dem inneren Schelf) in Betracht gezogen. Weiterhin werden die Plattformentwicklung- und Ablagerungen im Arbeitsgebiet mit zeitlich äquivalenten, publizierten Daten aus benachbarten Tethysraumes. Bereichen verglichen. Geländekampagnen,. der. Arabischen. und. Platte. diskutiert.. sedimentologischer,. Die. sowie. mit. Gebieten. Ergebnisse. biostratigraphischer. und. aus. des drei. fazieller. Untersuchungen an Lockerproben, Dünnschliffen und Makrofossilien sowie aus der quantitativen. Untersuchung. von. hochfrequenten. Karbonatzyklen. (Akkommodationszyklen) werden in drei Artikeln präsentiert, die veröffentlicht (Kapitel 2), beziehungsweise bei internationalen Fachzeitschriften eingereicht wurden (Kapitel 3 und 4). KAPITEL. 2. beinhaltet. eine. integrierte. Korrelation. lithologischer. und. multibiostratigraphischer Daten. Diese Korrelation bildet die Basis für ein neu entwickeltes, sequenzstratigraphisches Schema. Es beinhaltet acht sedimentäre Sequenzen und sieben Sequenzgrenzen und es ermöglicht eine großräumige NordSüd-Korrelation auf der Plattform. Diese Korrelation ergibt, daß das ‘Karak Limestone Member’ aus dem späten Cenoman das südliche stratigraphische Äquivalent der ‘Hummar Limestone Formation’ im Norden darstellt. Weiterhin wird das neue Modell mit globalen und regionalen sequenzstratigraphischen Schemata IV.

(7) Preface. aus Israel und Sinai verglichen. Darauf basierend wird angenommen, daß beide Transgressionen während des frühen Cenoman und des späten Turon, die begleitet werden durch Progradation und Aggradation der Karbonatplattform, eustatisch gesteuert sind, ebenso wie das Ertrinken der Plattform im Obercenoman bis Unterturon. Das Gleiche wird angenommen in Bezug auf den ausgeprägten Meeresspiegelniedrigstand, der durch Abfolgen des mittleren Turon widergespiegelt wird. Zusätzliche oder fehlende Sequenzgrenzen werden im Gegensatz dazu vorherrschend als Ergebnis untergeordneter Meeresspiegelvariationen interpretiert oder im Zusammenhang mit synsedimentärer regionaler Tektonik gesehen. Für die Zeit mittleres Cenoman bis mittleres Turon wird eine erhöhte Subsidenz im zentralen Arbeitsgebiet angenommen. In KAPITEL 3 unterstützt ein multibiostratigraphisches Schema eine hochauflösende Stratigraphie, wobei die biostratigraphischen Daten hauptsächlich auf Ammoniten und kalkigen Nannofossilien basieren, ergänzt durch Foraminiferen und Ostrakoden. Ammonitenvorkommen, welche die mantelli bis woollgari Biozonen belegen, erleichtern eine präzise Unterteilung von Ablagerungen aus dem Untercenoman bis zum. mittleren. Turon.. Weiterhin. unterstützen. drei. ammonitenführende. Markierungshorizonte die großräumige Korrelation von Abfolgen des obersten Cenoman bis mittleren Turon. Fünf Vergesellschaftungen benthischer Foraminiferen und zwei Ostrakodenassoziationen werden weiterhin eingeführt. Zudem werden fünf Einheiten definiert, die auf diesen neuen stratigraphischen und ökologischen Daten basieren, und die großräumig korreliert werden. Ferner ist eine Unterteilung der Plattformentwicklung in drei Phasen des Plattformwachstums und zwei Hauptphasen einer Plattformkrise möglich. Die erste Krise wird während des Mittelcenoman im zentralen Arbeitsgebiet beobachtet, während die zweite Krise während des Cenoman/Turon-Grenzintervals die gesamte Plattform beeinflußt. Beide Ereignisse werden durch Sedimentation im tieferen Wasser und lokal durch disoxische Bedingungen reflektiert. Diese sauerstoffarme Fazies verlagert sich während des späten Cenoman südwärts und kommt im zentralen Arbeitsgebiet wieder im frühen Turon vor. In KAPITEL 4 werden fünfzehn Mikrofaziestypen und acht Ablagerungsgebiete definiert und zu einem Faziesschema zusammengefaßt, welches die räumliche und V.

(8) Preface. zeitliche Korrelation wechselnder Lebens- und Ablagerungsräume auf dem Schelf unterstützt. Darüber hinaus ermöglicht eine Integration dieser Faziesdaten in den sequenzstratigraphischen graphischer. Bedingungen. Rahmen auf. (Kapitel 2). dem. Schelf. die und. Rekonstruktion einen. Vergleich. paleogeomit. der. Paläogeographie angrenzender Schelfgebiete in Israel und Ägypten. Daraus folgend wird eine erhöhte Subsidenz für das zentrale Arbeitsgebiet angenommen, die lokal (Gebiet des Wadi Al Karak) vom mittleren Cenoman bis zum mittleren Turon andauert. Subsidenz ereignete sich im Obercenoman bis Unterturon auch im Süden. Für das Gebiet des Wadi Mujib in Zentraljordanien wird im gleichen Zeitraum Inversion postuliert. Ähnliche Beckenstrukturen und Paläohochgebiete sind zur gleichen Zeit in Israel und Sinai zu beobachten. Disoxische Ablagerungen des tieferen Wassers sind an die Becken im zentralen und südlichen Gebiet gebunden. Statistische. Analysen. Akkommodationswechsel. rhythmisch und. gebankter. hochfrequente. Karbonate. Zyklizitäten,. die. als. ergeben teilweise. autozyklisch gesteuert aber überwiegend durch allozyklische Faktoren (vor allem Eustasie) initiiert, interpretiert werden. Diese Akkommodationsmuster werden in das bestehende sequenzstratigraphische Schema (Kapitel 2) integriert und korrelieren teilweise mit den zugehörigen sedimentären Sequenzen und Sequenzgrenzen.. Acknowledgements In the first place I would like to thank Prof. Dr. Jochen Kuss for the arrangement and initialisation of the present project and its financial support. His great support during two field trips, numerous discussions and helpful suggestions, as well as his review of the whole manuscript greatly improved this thesis. I also thank Prof. Dr. H. Willems for taking on the second expert report. Special thanks go to Dr. M. A. Hiyari (Director General) and Dr. B. Tarawneh, and our colleagues of the National Resources Authority (NRA) in Amman/Jordan, for the logistic support, and their valuable help in the field. Our field trips benefited significantly from the experience, the diplomatic finesse and the physical effort of Mr. Ahmed Gharaibeh (NRA, Amman/Jordan).. VI.

(9) Preface. Thanks are due to Prof. Dr. Zeev Lewy (Geological Survey, Jerusalem/Israel), who sampled and specified most ammonites and reviewed part of the manuscript. Thanks also go to Dr. A. M. Marzouk (Tanta University, Cairo/Egypt), who prepared and investigated the calcareous nannofossils, and to Prof. Dr. A. M. Bassiouni and Dr. A. M. Morsi (both Ain Shams University Cairo/Egypt), for their introduction to ostracodes and their help in ostracode specification. For various kinds of help and support I am indebted to my colleagues of the working group Geochronology of Bremen University. Erna Friedel improved the English of this thesis, and supported me with professional help and her warm personal encouragement. I thank Ralf Bätzel for the preparation of the thin sections and a helping hand for all types of technical problems. For various fruitful discussions and encouragement I warmly thank Dr. Martina Bachmann, Dr. Robert Speijer, Dr. Jan Bauer, Dr. Seb Lüning, Dipl. Geol. Markus Geiger, Dipl. Geol. Elisa Guasti and Dipl. Geol. Jacques Peeters. Special thanks go out to my room colleague Dr. Christian Scheibner who got nearly never tired to answer all kinds of questions. Considerable help was provided by Dr. John Reijmer (GEOMAR, Kiel) who reviewed parts of the manuscript and morally backed me . 'The project was funded by the German Research Foundation (DFG; Ku 642/16). Further financial support came from the University of Bremen (FNK). For the encouragement during the last period of the thesis I warmly thank Dr. Christoph Vogt (Bremen University). Dr. Jochen Knies (Norwegian Geological Survey) kindly provided support during the final editing and printing phase. Special thanks go to Hannelore Juhre, Ina Köhler and Irina Engelhardt for the continuous morally support during the whole period of this work. Meinen Eltern möchte ich besonders danken. Sie haben mich immer in jeder Hinsicht unterstützt - finanziell, moralisch und mit Liebe und Geborgenheit, die mir dabei geholfen haben, meinen Weg zu gehen. VII.

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(11) CONTENTS CHAPTER 1: Introduction. 1. 1.1. 1.2.. 3 6. Geological background Main objectives. CHAPTER 2:. Cenomanian-Turonian carbonate platform deposits in west central Jordan 15 1. Abstract 17 2. Introduction 18 3. Geological framework 20 3.1. Paleogeography 20 3.2. Sea-level changes 20 3.3. Tectonics 21 4. Methods 22 5. Biostratigraphy 24 5.1. Ammonites 24 5.2. Calcareous nannoplankton 25 5.3. Foraminifers 25 5.4. Ostracodes 27 6. Lithostratigraphy 27 6.1. Naur Formation 27 6.2. Fuheis Formation 29 6.3. Hummar Formation 31 6.4. Shueib Formation 33 6.5. Wadi As Sir Formation 34 6.6. Discussion of stratigraphic data 35 7. Environmental conditions 36 8. Sedimentary sequences (S1-S8) 37 8.1. Sequence 1 (S1) 37 8.2. Sequence 2 (S2) 40 8.3. Sequence 3 (S3) 40 8.4. Sequence 4 (S4) 41 8.5. Sequence 5 (S5) 42 8.6. Sequence 6 (S6) 43 8.7. Sequence 7 (S7) 43 8.8. Sequence 8 (S8) 44 9. Comparison with adjacent areas 45 9.1. Israel 45 9.2. Sinai/Egypt 48 9.3. Arabian Plate 49 9.4. Implications of the sequence scheme comparisons 51 10. Conclusions 52 Acknowledgements 53 References 53.

(12) CHAPTER 3:. The upper Albian to Turonian carbonate platform succession of west central Jordan-stratigraphy and crises 59 1. Abstract 61 2. Introduction 62 3. Methods 64 4. Lithology 65 4.1. Naur Formation 66 4.2. Fuheis Formation 68 4.3. Hummar Foirmation 68 4.4 Shueib Formation 68 4.5 Wadi As Sir Formation 69 5. Sequence stratigraphy 69 6. Biostratigraphy 70 6.1. Ammonites 70 6.2. Calcareous nannofossils 73 6.3. Benthic foraminifers 83 6.4. Ostracodes 92 6.5. Planktic foraminifers 95 7. Discussion 96 7.1. Integrated stratigraphical correlation 96 7.2. Paleoceanographic interpretations 101 8. Conclusions 103 Acknowledgements 104 References 105 CHAPTER 4:. Platform configuration, microfacies and cyclicities of the upper Albian to Turonian of west central Jordan 111 1. Summary 113 2. Introduction 114 3. Geological Framework 115 4. Stratigraphy 117 4.1. Lithostratigraphy 117 4.2. Biostratigraphy 117 4.3. Sequence stratigraphy 120 5. Methods. 120 6. Results 121 6.1. Microfacies 121 6.1.1. Skeletal Components 121 6.1.2. Non-skeletal components 124 6.1.3. Textures 125 6.1.4. Matrix and diagenesis 125 6.2. Environments of deposition 127 6.2.1. Peritidal facies belt 127 6.2.2. Shallow subtidal facies belt 129 6.2.3. Deep subtidal facies belt 130 6.2.4. Comparison with Sinai / Egypt 130 6.3. Cyclicities 132 6.3.1. Cyclicities of Cenomanian platform carbonates 132 6.3.2. Cyclicities of Turonian platform carbonates 134 6.3.3. Accommodation plots 135 6.3.4. Discussion 138.

(13) 6.4. Lateral and vertical distribution of facies belts 6.4.1. The northern part 6.4.2. The central part 6.4.3. The southern part 6.4.4. Discussion 6.5. Paleogeography 6.5.1. Interval A 6.5.2. Interval B 6.5.3. Interval C 6.5.4. Interval D 6.5.5. Interval E 6.5.6. Discussion 7. Conclusions Acknowledgements References. 140 140 142 143 145 145 145 148 148 149 149 150 151 152 153. CHAPTER 5: Conclusions and perspectives. 161. APPENDIX I: Study area, localities and sections. 167.

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(15) CHAPTER 1:. Introduction.

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(17) Chapter 1 Introduction. CHAPTER 1: Introduction The evolution of the upper Albian to Turonian carbonate platform in west central Jordan has been investigated based on an integrated stratigraphic framework as well as on microfacies and facies investigations. These data have been integrated into detailed depositional and paleogeographical models, which provide correlation on the Jordanian platform, with adjacent areas and with global schemes as well. During three field trips a total of 4080 m have been measured in thirty-six sections of twenty different localities (Fig. 1). 378 rock samples and 757 marl samples of these sections have been analysed. All further investigations that constitute the main topics of the thesis base on these analyses. 1.1 Geological background The Upper Cretaceous was an interval of a generally warmer climate and extensive sea-level rises. Carbonate platforms covered large parts of the shelfs along the Tethyan margins and of other marginal ocean areas. During late Albian to Turonian times the Arabian Plate was situated in an equatorial position in the Southern Tethyan realm. Passive margin and stable platform conditions dominated the evolution of the contained broad carbonate platforms (Bosworth et al., 1999; Sharland et al., 2001). Nevertheless, repeated transgressions over the marginal continental areas occurred and strongly influenced the platform development. The investigation of platform growth and crises as well as of faunal and environmental changes on the platform, are important to enhance the understanding of regional platform. evolution. and. its. controlling. factors. in. interaction. with. eustatic. oceanographic events. Paleogeography During late Albian to Turonian times the study area was part of a broad shallow carbonate platform (Levant Platform) that stretched from North Africa to the eastern margin of the Arabian Plate. It was situated on the passive margin of the Arabian Plate within the southern Tethyan realm (Philip et al., 2000). The generally lowangled shallow platform was predominantly subdivided into peritidal to shallow subtidal facies belts (Powell, 1989; Al-Rifay et al., 1993; Chapter 4).. 3.

(18) Chapter 1 Introduction. ne ra er. an. SYRIA. it ed M ea S. IRAQ. Caspian Sea. JORDAN. SINAI. ad Re. SAUDI ARABIA. OMAN. a Se. 0. 500 Km. after Sharland et al., 2001 fracture zone 36°00'. 37°00'. section city major Wadi. WS. -300-0m. SH RM2 RM3 RM4 BH AM. 0-300m 300-600m. 32°00'. 600-900m 900-1200m MA1. Sea. MA3. Dead. WH. MD2 MD1, 5, 6. WM. GM1,2. Wadi Abu Khusheiba. KU1-3. MA2. Wadi Mujib Wadi Al Karak. WK1,2 KB1,2 IR TB. 31°00'. AF1 AY SI1+2, 3. SI4. WB1, 2. P. 0. 25. 50 km. Wadi Musa 36°00'. 37°00'. Fig. 1: Overview map of Jordan and adjacent areas on the Arabian Peninsula; Enlarged box: Study area, localities and sections, the position of the main wadis is indicated (black arrows). 4.

(19) Chapter 1 Introduction. An increase of siliciclastics and a decrease of open marine facies conditions from north to south reflect a general shallowing towards the continent in the southeast (Powell, 1989). Deeper subtidal, occasionally restricted environments as well as lithology and thickness changes locally reflect paleo-relief differences in the central and southern study area. Moreover, a paleo-high was assumed by Powell (1989) further north in the area of Wadi Mujib (Fig. 1). A phase of paleo-relief changes separated two periods of comparatively uniform facies conditions during lower Cenomanian and upper Turonian times. The more 'active' period is reflected by middle to upper Cenomanian deposits and partly continued until the middle Turonian. Time-equivalent basin or graben-structures and paleo-highs are documented from adjacent shelf areas in Israel and Egypt (Chapter 4). Deep subtidal and open marine conditions established during upper Cenomanian to middle Turonian times in most parts of the study area (Chapter 4). Sea level A major eustatic transgression during late Albian to late Cenomanian times resulted in an early Turonian highstand and the most intense sea-level rise of the Phanerozoic (Haq et al., 1987). The highstand is overlain by a late early Turonian sea-level lowstand, followed by a second major transgression during late Turonian times. In the scheme of Hardenbol et al. (1998) the late Cenomanian transgression is represented by the 3rd order post-Ce5 transgression surface (Fig. 2) but there are differences in timing of the early Turonian highstand. Powell (1989) gives an overview about main transgressive and regressive phases in Jordan, while sequence stratigraphic models of adjacent areas partly contain detailed reconstructions of Cenomanian – Turonian sea-level variations (e.g. Buchbinder et al., 2000: Israel; Bauer et al., 2003: Sinai). Moreover, Sharland et al. (2001) established a comprehensive sequence stratigraphic framework for the Arabian Plate (Chapter 2). Lithological, environmental and ecological differences on the upper Albian to Turonian platform in Jordan (Chapter 3) as well as the platform architecture are strongly related to eustatic sea-level changes, which also caused three main steps of platform evolution in Jordan. A major transgression inducing platform progradation and carbonate aggradation during upper Albian to upper Cenomanian time is followed by an upper Cenomanian to lower Turonian platform flooding that caused an interruption of carbonate production, retrogradation, and depletion of the benthic 5.

(20) Chapter 1 Introduction. fauna. A middle to upper Turonian transgression triggered once more progradation and carbonate aggradation (Powell, 1989). Additionally, small-scaled carbonate shallowing-up cycles within Cenomanian and Turonian platform successions indicate higher-frequent sea-level changes (Chapter 4). Different interpretations have been suggested for the development of these cyclicities. An autocyclic control has been discussed as well as allocyclic. 95. Hardenbol et al. (1998). Oceanic Anoxic Event (OAE). CC Biozones. Hardenbol and Robaszysnki (1998). 3rd order Tethyan Sequences. Tu3. Tu2 turoniense nodosoides. CC 11. Lower. Ammonite biozones Southern Europe. Tu1. coloradoense. mfs. judii. geslinianum naviculare / pentagonum jukesbrownei. ts. CC 10. 94. CENOMANIAN. 93. M. Upper. 92. TURONIAN. 91. Middle. (Gradstein et al., 1995). Chronostratigraphy. mechanisms and a probable orbital forcing (Milankovitch cycles; Strasser, 1994).. rhotomagense. OAE 2. Ce5 Ce4. Fig. 2: Chronostratigraphy and biostratigraphy, which is based on ammonite biozones and calcareous nannofossil biozones (Hardenbol et al., 1998; Tethyan Realm) compared with a sequence stratigraphic scheme of the Tethyan Realm (ts: transgressive surface; mfs: maximum flooding surface); the interval of the OAE 2 is indicated in the right column. Cenomanian – Turonian anoxic events and their dating The late Cenomanian transgression and flooding of the Jordanian platform coincided with a platform crisis, dysoxic environments and an increased deposition of organicrich matter during the Cenomanian/Turonian-boundary interval (Fig. 2). The interaction between the eustatic sea-level rise (Haq et al., 1987), the platform crisis in Jordan and equivalent events during other time intervals and in adjacent areas are of special interest within this thesis. Dating and global comparison of sequence. 6.

(21) Chapter 1 Introduction. stratigraphic models and ocean / platform events are often problematic (Chapter 2 and 3). Bituminous strata occur in numerous shelf basins in North Africa and the Near East as well as in deep-sea basins of other oceans during Middle and Upper Cretaceous times (Schlanger and Jenkyns, 1976; e.g. Drzewiecki and Simo, 1997: Spain; Kuhnt et al., 1997: Morocco; Robaszynski et al., 1993a: Tunesia; Sharland et al., 2001: Arabian Plate). These organic-rich strata are generally linked to eustatic sea-level rises, positive peaks in the δ13C-isotope record and to marine anoxic events. The Cenomanian-Turonian Organic Anoxic Event is determined as the CTOAE 2 or Bonarelli Event (Fig. 2; Arthur, 1987; Schlanger et al., 1987; Jenkyns et al., 1994). Trigger and dating of the Upper Cretaceous anoxic events are still under discussion, despite extensive research of these topics. Different mechanisms are assumed to induce the deposition of the organic carbon-rich sediments. Stagnation and water stratification as a result from extensive sea-level rises is one model for the origin of anoxic deposits. An increase of primary productivity in combination with intensified upwelling is another model for the OAE 2 mechanisms. Tectonics and the paleorelief are likewise discussed as controlling factor. Additionally, the question is, which could be the most reliable stratigraphic basis for regional and global comparisons and dating of the major Cenomanian-Turonian transgression and the anoxic organic events on the platforms (and in deep ocean basins). A direct comparison of sequence stratigraphic schemes is often problematic. Different methods may be used to define systems tracts and sedimentary sequences. After Galloway (1989) maximum flooding surfaces separate genetic stratigraphic sequences, but in models of Vail et al. (1977) the sequence boundary is the main correlation tool. Furthermore, biostratigraphic data often constitute the base for global sequence stratigraphic correlations, but paleogeographic differences and varying biozonation schemes, e.g. between the Northern and Southern Tethyan realm, or between boreal and tethyal faunas, may cause mismatches within these biostratigraphic correlations. Nevertheless, an integrated approach of different fauna groups. and/or. other. stratigraphic. methods. (e.g.. isotope. stratigraphy,. cyclostratigraphy) enhance the stratigraphic framework. Gale et al. (2002) use ammonite and inonoceramid stratigraphy as a biostratigraphic frame for global correlations of Cenomanian sequences (between India and Europe). 7.

(22) Chapter 1 Introduction. On the other hand, Hancock (1993) mentions that the anoxic event during the late Cenomanian does not coincide with the main sea-level rise during the early Turonian and assumes mistakes in dating based on correlations of different biozonation schemes (foraminifers, ammonites, inocerames). Tectonics Deposition along the northern passive margin of the Arabian Plate took place on a stable shelf during upper Albian to Turonian times (Sharland et al., 2001). The main phase of compressive tectonic activities related to the Syrian Arc deformation belt that ranges from west Egypt to Syria is postulated for Santonian times (e.g. Bosworth et al. 1999). However, phases of subsidence and uplift are already reported for late Cenomanian to Turonian times from Jordan (Al-Rifaiy and Cherif, 1987; Powell, 1989; Kuss et al., 2000) and adjacent areas (Bartov and Steinitz, 1977; Buchbinder et al., 2000; Bauer et al., 2003), and are probably affected by initial Syrian Arc tectonics. 1.2 Main objectives The main targets of the present thesis are to verify environmental, faunal, and architectural changes during phases of growth and crises of the upper Albian to Turonian platform in Jordan, to investigate the interaction with eustatic sea-level changes and to figure out other possible controlling factors. An integrated stratigraphy framework, containing lithostratigraphic, biostratigraphic, sequence stratigraphic and cyclostratigraphic schemes as well as detailed microfacies and facies investigations, constitute the basis for these reconstructions. Lithostratigraphy and biostratigraphy (Chapter 2 and 3) To improve dating as well as small- and large-scale correlations of upper Albian to Turonian successions of Jordan, an enhanced biostratigraphic and lithostratigraphic framework is required. North to south correlation in the study area is problematic. Previous authors (Masri, 1963; Bender, 1974b; Powell, 1989) mainly correlated formation schemes, which predominantly based on lithological descriptions. Owing to a north to south shallowing trend (distal – proximal) and to additional paleo-relief differences, the lithologies and sedimentary patterns exhibit significant variations. Therefore, Powell (1989) constituted the F/H/S-undifferentiated Formation for central and south Jordan. Detailed lithostratigraphic investigations as well as new biostratigraphic data should 8.

(23) Chapter 1 Introduction. improve subdivision and correlation of this undifferentiated part of the succession, and particulary the determination of the Cenomanian/Turonian-boundary. Previous biostratigraphic studies often focussed on single fossil groups and/or time intervals (Wetzel and Morton, 1959; Aqrabawi, 1993; Bandel and Geys, 1985; Weidich and Al-Harithi, 1990; Babinot and Basha, 1985). Here it has to be considered that benthic organisms of shallow shelf areas are highly affected by environmental changes. Additionally, the investigated fauna groups and used biozonation schemes have to be comparable with other biostratigraphic models. Therefore, calcareous nannofossils and ammonites are investigated and compared with schemes of the Tethyan Realm (Hardenbol et al., 1998), the Near East (Lewy, 1989) and Southern Europe (Hardenbol and Robaszynski, 1998). Sequence stratigraphy (Chapter 2 and 4) A main objective is the establishment of a sequence stratigraphic scheme for the investigated platform succession. A sequence stratigraphic scheme supports the reconstruction of the environmental and the paleogeographic platform evolution and it improves integrated stratigraphic correlations on the platform. How many sequences and sequence boundaries will be established for Jordan? Can they be correlated with schemes from adjacent platform areas and with global models? Will a sequence stratigraphic scheme enable to recognise local, regional and global controlling mechanisms on the platform development? Faunal assemblages and paleoecology (Chapter 3) Detailed investigations of benthic and planktic fossil groups (benthic and planktic foraminifers, ostracodes, calcareous nannoplankton) are needed to highlight the impact of the different faunal groups as carbonate producers, to detect faunal differences between Cenomanian and Turonian assemblages and to reconstruct in which way these assemblages are influenced by platform flooding and crisis. Some benthic. and. planktic. microfossil. groups. constitute. sensible. indicators. for. environmental changes, such as variations in water depth, oxygen content, nutrient supply or water energy. Among the benthic organisms on upper Albian to Turonian platforms the study focusses on benthic foraminifers and ostracodes. Various studies about these groups as ecological proxies in Jordan and other areas have previously been presented (e.g. Weidich and Al-Harithi, 1990; Al-Rifay et al., 1993; Babinot and Basha, 1985, Holbourn et al., 1999). Ecologic assemblages of both fauna groups indicate the 9.

(24) Chapter 1 Introduction. lateral and vertical distribution of shallow shelf environments. Comparisons with faunal assemblages of adjacent areas may confirm uniform conditions on coherent platforms of the southern Tethyan margin, but they may also highlight regional environmental and depositional differences. A focus lies on the questions, why many larger benthic foraminifers disappeared during late Cenomanian times and did not resettle on Turonian platforms and how this development is connected with the global late Cenomanian sea-level rise and the regional evolution of the Jordanian platform. Moreover, assemblages of calcareous nannofossils constitute environmental proxies. Do their occurrence and distribution indicate changes of water depth, water temperature and nutrient supply? Cyclicities and Accommodation plots (Chapter 4) Small-scaled cycles occur within Cenomanian and Turonian platform carbonates. The questions are, if there are differences between the cycles of both time intervals, and how the cyclicities can be integrated into the sequence stratigraphic scheme of the study area. Another question is, if statistical analyses, using accommodation plots, will improve the investigation of the cyclic sedimentary patterns and the determination of the controlling factors. The small-scaled carbonate cycles predominantly consist of shallowing-up successions (subtidal to peritidal environments) with a dm to m scale. Changing lithologies, sedimentary patterns and faunal contents within the cyclic units characterise relative sea-level fluctuations. Statistically analyses of cycle thickness and number follow methods and advisements of Fischer (1964), Goldhammer et al. (1993), and Sadler et al., (1993). The accommodation plots are discussed with emphasis on the questions, whether they are useful tools for lateral correlation, whether they can be integrated into the sequence stratigraphic scheme, and whether they reflect autocyclic mechanisms or allocyclic and orbital forcing. Environmental changes and platform crises (Chapter 3 and 4) A main objective of this thesis is the reconstruction of lateral and vertical distribution of depositional environments on the platform. Which environments prevail during Cenomanian and Turonian times on the platform and which controlling factors triggered the differences? Are abrupt changes from shallow to deeper water conditions in upper Cenomanian times related to a global sea-level rise, and are comparable changes during other time-intervals observable? Deeper water environments, a decreasing carbonate 10.

(25) Chapter 1 Introduction. production, and decreasing faunal diversities during the Cenomanian/Turonianboundary interval are described from several shelf areas of the southern Tethyan realm (Drzewiecki and Simo, 1997; Grosheny and Tronchetti, 1993; Bauer et al., 2003; Lipson-Benitah et al., 1990). Are these conditions comparable to deposition of bituminous marls and claystones and a depletion of the benthic fauna on the Jordanian platform? Do these events relate to the same mechanisms that induced the global Cenomanian – Turonian Organic Anoxic Event (CTOAE 2; Jenkyns, 1980; Arthur et al., 1987)? Are these intervals of decreased carbonate production and platform crises also affected by regional/local factors (e.g. tectonics)? Will a facies model that contains lateral and stratigraphic distribution reflect relative sea-level changes and highlight paleo-relief variations? Paleogeography (Chapter 4) Paleogeographic reconstructions illustrate the lateral distribution of environments and their disposition during single time intervals. Additionally, paleogeographic maps visualise main structural elements of the platform. How are the facies belts arranged on the Cenomanian – Turonian platform during the main phases of sea-level rise and fall? Which kind of platform structuring can be reconstructed, considering the results of stratigraphic and environmental analyses? How corresponds the paleogeographic development in Jordan with that of adjacent areas? References Al-Rifaiy, I.A., Cherif, O.H. (1987): Biostratigraphic aspects and regional correlation of some Cenomanian/Turonian exposures in Jordan.- Géologie Méditerranéenne, XIV (3),181–193. Al-Rifaiy, I.A., Cherif, O.H. and El-Bakri, B.A. (1993): Upper Cretaceous foraminiferal biostratigraphy and paleobathymetry of the Al-Baqa area, North of Amman (Jordan).J. Afric. Earth Sci., 17 (3), 343–357. Aqrabawi, M. (1993): Oysters (Bivalvia – Pteriomorphia) of the Upper Cretaceous rocks of Jordan. Palaeontology, Stratigraphy and Comparison with the Upper Cretaceous oysters of Northwest Europe.- Mitt. Geol.- Paläont. Inst. Univ. Hamburg, 75, 1–135. Arthur, M.A., Schlanger, S.O. and Jenkyns, H.C. (1987): The Cenomanian-Turonian Oceanic Anoxic Event II. Palaeoceanographic controls on organic matter production and preservation.- In: Marine petroleum source rocks (Eds Brooks, J. and Fleet, A.J.).Geological Society of London, Special Publication 26, 401–420. Babinot, J.-F. and Basha, S. H. (1985): Ostracodes from the Early Cenomanian of Jordan. A preliminary report.- Geobios, 18 (2), 257-262. Bandel, K. and Geys, J.F. (1985): Regular echinoids in the Upper Cretaceous of the Hashemite Kingdom of Jordan.- Ann. Soc. Géol. Nord, CIV, 97–115. Bartov, Y. and Steinitz, G. (1977): The Judea and Mount Scopus groups in the Negev and Sinai with trend surface analysis of the thickness data.- Israel Journal of Earth Sciences, 26, 119-148.. 11.

(26) Chapter 1 Introduction Bauer, J., Kuss, J. and Steuber, T. (2003): Sequence architecture and carbonate platform configuration (late Cenomanian –Santonian), Sinai, Egypt.- Sedimentology, 50, 1–28. Bender, F. (1974b): Explanatory notes on the geological map on the Wadi Araba, Jordan (scale 1:100000, 3 sheets).- Geol. Jb., 10, 3–62. Bosworth, W., Guiraud, R., Kessler, L.G. (1999): Late Cretaceous (ca. 84 Ma) compressive deformation of the stable platform of northeast Africa (Egypt): Far-field stress effects of the “Santonian event“ and origin of the Syrian arc deformation belt.- Geology, 27(7), 633–636. Buchbinder, B., Benjamini, C. and Lipson-Benitah, S. (2000): Sequence development of Late Cenomanian –Turonian carbonate ramps, platforms and basins in Israel.- Cret. Res., 21, 813–843. Drzewiecki, P. A. and Simo, J. A. (1997): Carbonate platform drowning and oceanic anoxic events on a Mid-Cretaceous carbonate platform, South-Central Pyrenees, Spain.Journal of Sedimentary Research, 67, 698-714. Fischer, A.G. (1964): The Lofer cyclothems of the alpine Triassic.- Kansas Geological Survey Bulletin, 169, 107-149. Gale, A.S., Hardenbol, J., Hathway, B., Kennedy, W.J., Young, J.R. and Phansalkar, V. (2002): Global correlation of Cenomanian (Upper Cretaceous) sequences: Evidence for Milankovitch control on sea level.- Geology, 30 (4), 291-294. Galloway, W.E. (1989): Genetic Stratigraphic Sequences in Basin Analysis I: Architecture and Genesis of Flooding Surface Bounded Depositional Units.- American Association of Petroleum Geologists Bulletin, 73, 125-142. Goldhammer, R.K., Lehmann, P.J. and Dunn, P.A. (1993): The origin of high-frequency platform carbonate cycles and third-order sequences (Lower Ordovician El Paso Gp, West Texas): constraints from outcrop data and stratigraphic modeling.- J. of Sed. Petr., 63 (3), 318-359. Grosheny, D. and Tronchetti, G. (1993): La crise Cénomanien-Turonien: Réponse comparée des assemblage de foraminifères benthiques de plate-forme carbonatée et de bassin dans le Sud-Est de la France.- Cret. Res., (14), 397-408. Hancock, J.M. (1993): Sea-level changes around the Cenomanian – Turonian boundary.Cret. Res., 14, 553-562. Haq, B., Hardenbol, J. and Vail, P.R. (1987): Chronology of fluctuating sea levels since the Triassic.- Science, 235, 1156–1167. Hardenbol, J., Thierry, J., Farley, M.B., Jacquin, T., De Graciansky, P.-C. and Vail, P.R. (1998): Mesozoic and Cenozoic sequence chronostratigraphic framework of European basins.- In: Mesozoic and Cenozoic sequence stratigraphy of European basins (Eds De Graciansky, P.-C., Hardenbol, J., Jacquin, T. and Vail, P.R.).- SEPM Special Publication, 60, 343–360. Hardenbol, J. and Robaszynski, F. (1998): Introduction to the Upper Cretaceous.- In: Mesozoic and Cenozoic sequence stratigraphy of European basins (Eds De Graciansky, P.-C., Hardenbol, J., Jacquin, T. and Vail, P.R.).- SEPM Special Publication, 60, 329–332. Holbourn, A., Kuhnt, W., El Albani, A., Pleitsch, T., Luderer, F. and Wagner, T. (1999): Upper Cretaceous palaeoenvironments and benthonic foraminiferal assemblages of potential source rocks from the western African margin, Central Atlantic.- In: The Oil and Gas Habitats of the South Atlantic (Eds Cameron, N. R., Bate, R. H. and Clure, V. S.).- Geological Society, London, Special Publications, 153, 195-222. Jenkyns, H.C. (1980): Cretaceous anoxic events – from continents to oceans.- Journal of the Geological Society of London, 137, 171–188. Jenkyns, H.C., Gale, A.S. and Corfield, R.M. (1994): Carbon- and oxygen-isotope stratigraphy of the English Chalk and Italian Scaglia and its paleoclimatic significance. Geol. Mag., 131, 1-34. Kuhnt, W., Nederbragt, A. and Leine, L. (1997): Cyclicity of Cenomanian – Turonian organiccarbon-rich sediments in the Tarfaya Atlantic coastal basin (Morocco).- Cret. Res., 18, 587-601.. 12.

(27) Chapter 1 Introduction Kuss, J., Westerhold, T., Groß, U., Bauer, J. and Lüning, S. (2000): Mapping of Late Cretaceous stratigraphic sequences along a Syrian Arc uplift – Examples from the Areif el Naqa, Eastern Sinai.- Middle East Research Center, Ain Shams University, Earth Science Series, 14,171–191. Lewy, Z. (1989): Correlation of lithostratigraphic units in the upper Judea Group (Late Cenomanian – Late Coniancian) in Israel.- Isr. J. Earth Sci., 38, 37–43. Lipson-Benitah, S., Flexer, A., Rosenfeld, A., Honigstein, A., Conway, B., Eris, H. (1990): Dysoxic sedimentation in the Cenomanian–Turonian Daliyya Formation, Israel.AAPG, Studies in Geology, 30, 27–39. Masri, M. (1963): Report on the geology of the Amman-Zerqa area.- Central water authority, 1–74 (unpublished); Amman, Jordan. Robaszynski, F., Amédro, M. and Caron, M. (1993a): La limite Cénomanien-Turonien et la Formation Bahloul dans quelques localités de Tunisie Centrale.- Cret. Res., 14, 477486. Sadler, P.M., Osleger, D.A. and Montanez, I.P. (1993): On the labeling, length and objective basis of Fisher Plots.- J. of Sed. Petr., 63, 360-368. Schlanger, S.O. and Jenkyns, H.C. (1976): Cretaceous oceanic anoxia events: causes and consequences.- Geologie en Mijnbouw, 55, 179-184. Schlanger, S.O., Arthur, M.A., Jenkyns, H.C. and Scholle, P.A. (1987): The Cenomanian – Turonian oceanic anoxic event, I. Stratigraphy and distribution of organic-rich beds and the marine D13C excursion.- In: Marine Petroleum Source Rocks (Eds Brooks, J. and Fleet, A.J.).- Geol. Soc., London, Spec. Publ., 26, 371-399. Sharland, P.R., Archer, R., Casey, D.M., Davies, R.B., Hall, S.H., Heward, A.P., Horbury, A.D. and Simmons, M.D. (2001): Arabian Plate sequence stratigraphy.- GeoArabia Spec. Publ., 2, Bahrain, pp 371. Strasser, A. (1994): Milankovitch cyclicity and high-resolution sequence stratigraphy in lagoonal-peritidal carbonates (Upper Tithonian-Lower Berriasian, French Jura mountains).- In: Orbital Forcing and Cyclic Sequences (Eds de Boer, P.L. and Smith, D.G.).- Spec. Publ. Int. Ass. Sediment., 19, 285-301. Philip, J. et al. (12 co-authors) (2000): Late Cenomanian. In: Atlas Peri-Tethys palaeogeographical maps (Eds Dercourt, J., Gaetani, M., Vrielynck, B., Barrier, E., Biju-Duval, B., Brunet, M.F., Cadet, J.P., Crasquin, S. and Sandulescu, M.).- Map 14., CCGM/CGMW, Paris. Powell, J.H. (1989): Stratigraphy and sedimentation of the Phanerozoic rocks in Central and South Jordan. Pt. B: Kurnub, Ajlun and Belqa groups.- National Resources Authority Geol. Bull., 11, pp130. Vail, P.R., Mitchum, R.M., Todd, R.G., Widmier, J.M., Thompson III, S., Sangree, J.B., Bubb, J.N. and Hatelid, W.G. (1977): Seismic Stratigraphy and Global Changes of Sealevel.- In: Seismic Stratigraphy – Applications to Hydrocarbon Exploration (Ed Payton, C.E.).- American Association of Petroleum Geologists, 26, 49–212. Weidich, K. F. and Al-Harithi, T. (1990): Agglutinated foraminifera from the Albian and Cenomanian of Jordan.- In: Paleoecology, biostratigraphy, paleoceanography and taxonomy of agglutinated foraminifera (Eds Hemleben, C., Kaminski, M. A., Kuhnt, W. and Scott, D. B.).- NATO ASI 327 (C), Kluwer Academic Publishers, Dordrecht, 587609. Wetzel, R. and Morton, D. M. (1959): Contrabution a la géologie de la Transjordanie.Museum National d‘ Histoire Naturelle, Paris, Notes et Mémoires sur le Moyen-Orient, Notes 7, 95-191.. 13.

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(29) CHAPTER 2:. Cenomanian – Turonian carbonate platform deposits in west central Jordan. Frauke Schulze, Zeev Lewy, Jochen Kuss and Ahmed Gharaibeh (2003): International Journal of Earth Sciences, 92 (4): 641-660..

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(31) Chapter 2 Cenoman-Turonian carbonate platform deposits. Cenomanian-Turonian carbonate platform deposits in west central Jordan Frauke Schulze1, Zeev Lewy2, Jochen Kuss1 and Ahmed Gharaibeh3 1 Bremen University, Department of Geoscience, PO Box 330440, 28334 Bremen fschulze@uni-bremen.de, Phone: 49-421-218-4512; Fax: 49-421-218-4515 2 Geological Survey of Israel, 30 Malkhe Yisrael St., Jerusalem 95501, Israel 3 Natural Resources Authority, PO Box 7, Amman, Jordan. 1. Abstract We studied upper Albian to Turonian shallow-marine shelf deposits (Ajlun Group) of west central Jordan along a NNE-SSW running transect. The carbonate-dominated succession includes few siliciclastic intercalations, claystones and shales, and can be subdivided into five formations. The Naur, Fuheis and Hummar Formations of upper Albian to upper Cenomanian age represent shallow subtidal to supratidal platform environments. The uppermost Cenomanian to middle Turonian Shueib Formation includes deeper water deposits of the inner/mid shelf and locally TOC-rich black shales. Shallow-marine platform environments once again dominate the Wadi As Sir Formation (middle-upper Turonian). A new multibiostratigraphic framework is based on ammonites (mainly of the middle Cenomanian rhotomagense Zone to the middle Turonian woollgari Zone) and calcareous nannofossils (biozones CC 9 – CC 11), supplemented by benthic and planktic foraminifers and ostracodes. It forms the base of a sequence stratigraphic subdivision, containing eight sedimentary sequences (S1 – S8), which are separated by four Cenomanian sequence boundaries (CeJo1 – CeJo4) and three Turonian sequence boundaries (TuJo1 – TuJo3). This scheme allows the correlation of the platform succession from distal to proximal shelf areas in contrast to previous correlations using lithologic units. Furthermore, comparisons between the platform successions and sequence patterns of west central Jordan and those from neighbouring areas allow to differentiate local, regional, and global controlling factors of platform development within the study area.. 17.

(32) Chapter 2 Cenoman-Turonian carbonate platform deposits. Key words West central Jordan, upper Albian – Turonian, carbonate platform, lithology, sedimentary sequences. 2. Introduction The purpose of the present work is to improve the stratigraphy of the upper Albian to Turonian platform succession of west central Jordan, to provide long-distance correlations,. and. to. reconstruct. the. shelf. architecture.. Therefore,. new. lithostratigraphic and biostratigraphic data are referred to and a new sequence stratigraphic scheme for the study area has been established. The presented sequential scheme is used to enhance the vertical and lateral formation correlation within the study area, which, in places has been quite problematic. Moreover, local and regional comparisons of the distinguished sedimentary sequences to those from adjacent areas, enable to reconstruct the depositional history of the investigated shelf area and to figure out associated controlling factors. Furthermore, the new biostratigraphic framework is mainly based on ammonites and calcareous nannofossils, while foraminifers and ostracodes that are more strongly affected by facies only supplement the biostratigraphic frame. Previous biostratigraphic studies on the Ajlun Group included ammonites (e.g. Wetzel and Morton 1959; Nazzal and Mustafa 1993), bivalves (Aqrabawi 1993), echinoids (Bandel and Geys 1985), and foraminifers (e.g. Basha 1979; Al-Rifaiy and Cherif 1987; Al-Rifaiy et al. 1993, Weidich and Al-Harithi 1990). Comparisons with biostratigraphic records from adjacent countries (Egypt: Abdel-Kireem 1988; Shahin and Kora 1991; Orabi 1992; Israel: Freund and Raab 1969; Lewy et al. 1984; Lebanon: Hamaoui and Saint-Marc 1970) allow to improve the regional correlation of the Cenomanian-Turonian succession and the paleogeographic reconstruction, the oceanographic settings and the timing of geological events. Lithostratigraphic schemes of the upper Cretaceous of Jordan were discussed in previous presentations by Masri (1963), MacDonald (1965b), Bender (1974b), Parker (1970), and Powell (1988; 1989b). These studies and the observations presented here reflect profound lateral changes in lithology and biofacies throughout Jordan.. 18.

(33) Chapter 2 Cenoman-Turonian carbonate platform deposits. Fig. 1.: Working area (map inset) and locations of the studied sections in west central Jordan: WS: Wadi Salihi; RM2-4: Rumaymin; BH: Bahhath; AM: Amman; MA1-3: Wadi Abu Khusheiba; KU1-3: Wadi Abu Kusheiba; WH: Wadi al Hidan; WM: Wadi Mujib; MD1: Mujib Dam; MD2, 5+6: Wadi Mujib; GM1+2: Ghawr al Mazra’a; WK1+2: Wadi Al Karak; KB1+2: Kuthrubba; IR: Al Iraq; TB: At Talibbiya (Khanzira); AF: Afra Springs; AY: Ayma; SI1+2: Silla; SI3, 4: Silla; WB: Wadi Bustani; P: Wadi Musa/Petra. Sections in black are ‘reference sections’ of this work (see Figs. 5-8, 10). Arrows indicate four major wadis.. 19.

(34) Chapter 2 Cenoman-Turonian carbonate platform deposits. 3. Geological framework The investigated upper Albian to Turonian deposits (Ajlun Group) of west central Jordan are dominated by carbonate lithologies that overlie the terrigenous clastics of the Kurnub Group. The well-exposed Upper Cretaceous deposits exhibit significant lithologic and facies changes from north to south. These lateral variations are discussed with respect to the following three factors controlling platform development. 3.1 Paleogeography During late Albian to Turonian times, the study area was part of a NW-dipping carbonate platform, situated on the passive margin of the Arabo-Nubian shield (Powell 1989b). The Jordanian shelf was part of the Levant Platform, extending from Syria in the northeast to Egypt in the southwest. The late Cenomanian WSW-ENE running paleo-coastline ranged from southeast Jordan to present-day northwest Saudi Arabia (Philip et al. 2000, Fig. 2). Sedimentation occurred on a broad shelf, where a local basin-swell morphology separated calcareous lithologies of middle Cenomanian to lower Turonian age in the north and south of the study area from thick marly and clayey intercalations in the centre. Towards the south, an increased input of nearshore siliciclastics can be observed (Powell 1989b; Al Rifaiy and Cherif 1987; Abed and El-Hiyari 1986). 3.2 Sea-level changes Relative sea-level changes are expressed in lithologic and facies changes of the studied succession. Powell (1989b) described the following major sea-level fluctuations for the studied Ajlun Group. A major transgression is represented by late Albian to earliest Turonian deposits, reflecting mainly shallow-marine environments (peritidal to subtidal), locally with high-energy areas (shoals, patch reefs). Sediments deposited in open-marine, deeper subtidal shelf environments mark the early Turonian highstand that occurs coevally with a eustatic sea-level rise and an organic anoxic event (OAE 2; e.g. Jenkyns 1980; Arthur et al. 1987, Haq et al. 1987). They are overlain by late early Turonian lowstand sediments deposited in shallow intertidal to supratidal environments. A second major transgression is evidenced by late Turonian deposits, reflecting high-energy conditions in the lower part and shallow intertidal environments in the upper part. 20.

(35) Chapter 2 Cenoman-Turonian carbonate platform deposits. Late Cenomanian. Ru Hi tba gh h. nt va . L e Pf. Kufra Basin. Haifa. Arabian Shield. Jerusalem. Cairo. JOR. Ne. ge. v. DAN. Port Said. Amman. Aqaba. SINAI. EGYPT. SAUDI ARABIA RED SEA. Deep marine Deeper carbonates, hemipelagic oozes Shallow marine carbonate deposits Coastal marine, shallow marine (terrigenous). Fluvio-lacustrine Exposed land Study area Present-day coastline Paleo- coastline. Fig. 2: Paleogeographic map (inlay) that illustrates late Cenomanian facies belts on the Arabian Shield (simplified after Philip et al. 2000). Enlarged map: Segment of the Levant Platform, covering northeast Egypt, Sinai and Jordan, including the study area (stippled box, see legend).. 3.3 Tectonics The upper Cretaceous platform sedimentation of Jordan and adjacent areas was significantly affected by the Syrian Arc deformation belt ranging from west Egypt to Syria. The main phase of the compressive tectonic activities is postulated for 21.

(36) Chapter 2 Cenoman-Turonian carbonate platform deposits. Santonian times (e.g. Bosworth et al. 1999) but initial Syrian Arc tectonics of late Cenomanian age were discussed by Kuss et al. (2000; Egypt) and Al-Rifaiy and Cherif (1987; Jordan). In addition, Bauer (2002; Sinai) assumed local subsidence during the upper Cenomanian and, in places, inversive tectonics (uplift) during the lower Turonian.. 4. Methods Thirty-four sections situated in west central Jordan (Fig.1) were measured in detail, including descriptions of sedimentary patterns observed in the field. Petrographic and microfacies analyses were carried out on 463 rock samples, as well as nannofossil and microfossil investigations of 626 marl and shale samples. Ten ammonite genera and 14 species were identified in the field and provided preliminary information about the stratigraphic position of the exposures. Lithofacies interpretations of thin sections are based on classifications of Dunham (1962), microfacies categories were defined according to Wilson (1975) and include semiquantitative estimations of the main components based on the estimation pictures of Bacelle and Bosellini (1965). The latter scheme divides the abundance of components in percentages from 10% to 60% with 0%=absent; 10%=very rare; 20%=rare; 30-40%=common; 50-60%=abundant. The thin sections were additionally used for taxonomic studies of benthic foraminifers. Friable samples were disintegrated with water or were soaked in a 0.5 molar Na2CO3 solution. Samples with a higher content of organic matter were disintegrated with a H2O2 (35%) solution. REWOQUAT (CH3OSO3-) was added to clayey marl and shale samples. Fig. 3 (opposite page): Multibiostratigraphic frame of the studied late Albian to Turonian deposits, based on ammonites, calcareous nannofossils, planktic and benthic foraminifers and ostracodes, calibrated with the chronostratigraphy of Gradstein (1995), and ammonite biozonation schemes of Southern Europe (Hardenbol and Robaszynski in de Graciansky et al. 1998) and the Near East (Lewy and Raab 1976; Freund and Raab 1969 modified by Lewy 1989). Boundaries of new sedimentary sequences are indicated. Local ranges of ammonites are compared with those from Israel and Sinai/Egypt. Local ranges of benthic foraminifers are compared with Schroeder and Neumann (1985), local ranges of planktic foraminifers are compared with Caron (1985), and Premoli Silva and Sliter (1999).. 22.

(37) 100. 95. 93.5 (+0.2) -. Albian u. 98.9 (+0.6) -. l. m. u. Turonian m. u. (WJ). a. b. c. d. KL. WL. Kurnub Sandstone (KS). Naur Limestone (NL). Hummar (H) Fuheis (F). Shueib (S). Wadi As Sir Limestone (WSL). Sedimentary sequences. S1. S2. S4 S3. S5. S7 S6. S8. mantelli. dixoni. rhotomagense. judii geslinianum guerangeri jukesbrownei. coloradoense. nodosoides. woollgari. Near East T5 T4 T3 T2 T1. T6b T6a. T7. Kassab (1994) Kassab and Obaidalla (2001). Bauer et al. (2001). Sinai/Egypt. Lewy (1989), Lewy and Raab (1976) Freund and Raab (1969). Israel. this work. Jordan. Turrilites acutus Neolobites vibrayeanus Metoicoceras geslinianum Burroceras transitorium. Proeucalycoceras haugi. Time in Ma. 90. 89.0 (+0.5) -. Southern Europe. Vascoceras cauvini Choffaticeras pavillieri (juv.) C. securiforme (not in situ) V. durandi Thomasites rollandi Ch. quaasi Fagesia lenticularis Ch. luciae. Sampled ammonites and ranges from adjacent areas. Eiffelithus turriseiffelii. CC 9. Microrhabdulus decoratus. CC 10. Quadrum gartneri. CC 11. benthic. Planktic and benthic foraminifers planktic. Schackoina cenomana. GRADSTEIN et al. (1995). Cenomanian. Calcareous nannofossils biozonation. Whiteinella archaeocretacea Whiteinella aprica. Mrhiliceras lapparenti. Ammonite zones and ranges. Orbitolina corbarica Praealveolina iberica Ovalveolina crassa. Formations and Members. Praealveolina cretacea. Standard Chronostratigraphy. Chrysalidina gradata. Praealveolina tenuis. Caron (1985). Premoli Silva and Sliter (1999). Schroeder and Neumann (1985). local ranges (this work). Veeniacythereis streblolophoda schista. V. maghrebensis. Cythereis mdaourensis. Indicative ostracods. Chapter 2 Cenoman-Turonian carbonate platform deposits. 23.

(38) Chapter 2 Cenoman-Turonian carbonate platform deposits. For many of the samples, disintegration and washing processes had to be repeated several times. The dried residue was sieved and split into three grain-size fractions: 63-125 µm; 125-630 µm; >630 µm. Predominantly the first two fractions were used to determine a semiquantitative abundance of the main microfauna groups (benthic and planktic foraminifers, ostracodes) and for biostratigraphic analyses under a light microscope. The calcareous nannofossils were studied in smear slides under a light microscope (cross-polarised, phase-contrast illumination) following the method of Bramlette and Sullivan (1961) and Hay (1965). Semiquantitative estimations of the preservation, the total floral content and the species frequencies have been done at a magnification of x 1000. Species abundance was classified as very rare= 1 specimen per slide; rare= 1 specimen per >50 fields of view; few= 1 specimen per 10-50 fields of view; common= 1 specimen per 1-10 fields of view; abundant= >1 specimen per 1 field of view (pers. com. A. Marzouk). Eleven sections, out of the thirty-four measured outcrop sections, are used as ‘reference’ sections. They are illustrated in figures 5-8 and 10 and described in more detail in the text. The study area was divided into a northern (sections SH, RM2, RM4; Fig. 1), a central (sections MA2, MA3, MD1, MD5, MD6, WK2; Fig. 1), and a southern part (sections SI1+2, WB; Fig. 1) following lithological and environmental changes along the investigated platform transect going from north to south.. 5. Biostratigraphy A multibiostratigraphic approach was used to date the Cenomanian-Turonian deposits. The most indicative groups are ammonites and calcareous nannofossils. They are supplemented by benthic and planktic foraminifers and ostracodes (Fig. 3). Local ranges of ammonites, calcareous nannofossils and foraminifers are shown in figures 5-8. 5.1 Ammonites The study follows the ammonite zonation schemes of Israel (Freund and Raab 1969; Lewy and Raab 1976, Lewy 1989, 1990) and southern Europe (Hardenbol et al. 1998). They are illustrated in figure 3 together with local ranges of sampled specimens (this work) and ammonite ranges from adjacent areas (Egypt: Kassab 1994, Kassab and Obaidalla 2001, Bauer et al. 2001; Israel: see above). Several ‘ammonite beds’ observed within the investigated succession, and local ranges of the 24.

(39) Chapter 2 Cenoman-Turonian carbonate platform deposits. ammonite species are illustrated in outcrop sections (Figs. 5-8). The new biostratigraphic data, based on ammonite occurrences, enable to subdivide the upper Cenomanian – lower Turonian deposits and to improve long-range correlations within the study area. Wetzel and Morton (1959) investigated the stratigraphic position of Turonian ammonites from Jordan. Taubenhaus (1920) described Cenomanian-Turonian ammonites of Jordan, collected by M. Blanckenhorn. Nazzal and Mustafa (1993) described Cenomanian ammonites from northern Jordan. Local ranges of this work coincide predominantly with such described by previous authors. 5.2 Calcareous nannoplankton The study follows the zonation of Sissingh (1977), Perch-Nielsen (1985) and Burnett (1996), compared to the biochronozones of the Tethyan realm according to van Salis in Hardenbol et al. (1998). The Cenomanian-Turonian deposits of 12 sections yielded a rich nannoplankton flora of biozones CC 9, CC 10, and CC 11, based on 26 genera and 41 species. The local ranges of the index fossils and biozones are illustrated exemplarily in figures 5-8 and are summarised in a biostratigraphic scheme (Fig. 3). Following Robaszynski et al. (1990), and von Salis in Hardenbol et al. (1998) we defined the base of CC 11 Zone as the Cenomanian-Turonian boundary. 5.3 Foraminifers Benthic foraminifers were described in limestone thin-sections, and classified after Hamamoui and Saint-Marc (1970), Saint-Marc (1974) and Schroeder and Neumann (1985). The washed-out specimens were compared with those from previous records of Jordan (e.g. Koch 1968; Basha 1979; Weidich and Al-Harithi 1990; Al-Rifay et al. 1993). Six species of larger benthic foraminifers are used to distinguish the Cenomanian deposits (Fig. 3). Planktic foraminifers were classified after Caron (1985) and Premoli Silva and Sliter (1999). Three stratigraphically indicative species of planktic foraminifers are illustrated in figure 3.. 25.

(40) N. WL. Karak Limestone. 'c' 'b'. Naur Formation. Fuheis (F). KL. d. Naur (NL). Wadi Juheira (WJ). c a (WJ). ammonite-bearing horizons. limestone. alveolinid foraminifers. nodular limestone. orbitolinid foraminifers. marly limestone. rudist 'patch reefs'. TST. marl. planktic foraminifers. clayey marl. gastropods. HST highstand systems tract. Oy. claystone and gypsum. B. u. m. l u. thin lamination reworked clasts. cyclic stacking patterns trangressive systems tract. LST. lowstand systems tract. oysters. WJ. Wadi Juheira Member (member a). bivalves. KL. Karak Limestone Member. bioturbation. WL. Wala Limestone Member. echinoids. shale. not exposed/ not investigated. l. b. dolomite/ dolomitic limestone. siltstone/ sandstone. m. CENOMANIAN. Naqb Limestone. Hummar (H). 'd'. claystone. u. Shueib (S). Fuheis Formation. Naur Formation. Lithology (generalized). ALB.. Fuheis Formation. Hummar Formation. S. Wadi As Sir (WSL). Walla Limestone. Shuayb Formation F/H/S (undiff.). Hummar Formation. N. Wadi As Sir Formation. AJLUN GROUP. Shueib Formation. S Khureij Fm.. Wadi Es Sir Formation. Formations and Members. Members. TURONIAN. Formations. 280m. Group. adopted by Parker (1970). This work. POWELL (1989). MASRI (1963). Stage Substage. Chapter 2 Cenoman-Turonian carbonate platform deposits. 'hardground' with vertical burrows. Fig. 4: Lithostratigraphic subdivision of the studied upper Albian to Turonian succession of Jordan. Formation schemes of previous studies are compared with the system used in this work. Explanation of symbols and signatures, used in figures 3, 4-8 and 10a, b.. 26.

(41) Chapter 2 Cenoman-Turonian carbonate platform deposits. 5.4 Ostracodes Our data correspond to the ostracod biozonation of Israel (e.g. Rosenfeld and Raab 1974). Similar assemblages of Cenomanian-Turonian age were reported from Sinai (Shahin 1991; Bauer et al. 2001; Morsi and Bauer 2001) and Lebanon (Damotte and Saint-Marc 1972). The most indicative species are listed in figure 3. The Albian-Turonian marine successions of northern and central Jordan belong to the Ajlun Group (Quennell 1951) which comprises six formations: Naur Limestone (NL), Fuheis (F), Hummar (H), Shueib (S), Wadi As Sir Limestone (WSL) and Khureij Limestone (Masri 1963; Parker 1970; Powell 1989b; Fig. 3). Sedimentological characteristics of these formations are described by Powell (1988, 1989b). Our definition of the formations, main characteristics and new stratigraphic data are summarised in the following paragraphs and are illustrated in a generalised scheme (Fig. 4) and by four outcrop sections from the northern, central and southern study area (Figs. 5-8; for a precise location see Fig. 1). 6. Lithostratigraphy 6.1 Naur Formation (Masri 1963) The stratigraphic range of the Naur Formation covers upper Albian – lower middle Cenomanian times based on calcareous nannofossil zone CC 9 and occurrences of larger benthic foraminifers (Figs. 3, 5, 8). The Naur Formation can be subdivided into four members. The lowermost Wadi Juheira Member (member a) is overlain by members b, c, and d. Our field-based data show a total thickness up to 140m in northern sections (WS, Fig. 1) and 150m near Wadi Abu Khusheiba (section MA1, Fig. 1) in the central part of the study area. Near Wadi Al Karak (Fig. 1) and south of it (sections IR and AF; Fig. 1), the thickness Fig. 5: (next side left): Measured primary section RM2 from the northern study area (see Fig. 1). Stratigraphic, lithologic and sequence stratigraphic framework shown in columns on the left. Local ranges of biostratigraphically significant species are indicated on the right. Fig. 6: (next side right): Measured primary section RM4 from the northern study area (see Fig. 1). Stratigraphic, lithologic and sequence stratigraphic framework shown in columns on the left. Local ranges of biostratigraphically significant species are indicated on the right. For explanation of symbols, signatures and abbreviations see legend Figure 4.. 27.

(42) TST. a. 28. Oy. Oy Oy. Oy. TST. ?. CeJo2. HST. Oy. HST. Orbitolina spp. Orbitolina corbarica Praealveolina iberica Praealveolina cretacea Ovalveolina crassa Chrysalidina gradata. Foraminifers. Mrhiliceras lapparenti Proeucalycoceras haugi. Formation. Substage. 2m. TST. WSL (150m). M. Turonian. Oy Oy. WL. Oy Oy Oy Oy. Ammonites. and. Lower Turonian. Oy. TST. Formation. Substage. Systems tracts. HST. HST. Fuheis. Middle Cenomanian Oy. Shueib. d (168m). Upper Cenomanian. TST. c. Rumaymin Sequence RM2 boundaries. Hummar. HST. Naur. 2m. TST. b. Lower Cenomanian. (267m). and. Systems tracts. TuJo1. Oy. Oy. Oy. CeJo1. CeJo4. Rumaymin Sequence RM4 boundaries Choffaticeras pavilieri (juv.) Choffaticeras quaasi Thomasites rollandi. Ammonites. Chapter 2 Cenoman-Turonian carbonate platform deposits.

(43) Chapter 2 Cenoman-Turonian carbonate platform deposits. decreases to 90-100m and even to 10-30m in the southernmost sections (SI1+2, WB; Figs. 1, 6). Thus, a clear north to south trend of decreasing thickness can be observed. The Naur Formation is mainly composed of nodular and dolomitic limestones/dolomites (mainly members b, d) with subordinate marls (mainly in members a, c). In the northern and central sections (RM2, Fig. 5; WM, Fig. 1), the lowermost part of the formation, the Wadi Juheira Member (member a), is characterised by marls and marly (nodular) limestones, while silty or sandy marls and sandstones with local occurrences of glauconite peloids predominate member a in the southern sections (SI1+2, Fig. 8). Characteristical of members b and d are occurrences of small rudist ‘patch reefs’ (sections RM2, SI1+2; Figs. 5, 8). Furthermore, bioclastic limestones comprising a highly diverse benthic fauna and abundant larger benthic foraminifers characterise both members in the entire working area (sections RM2, SI1+2; Figs. 5, 8). Moreover, shallowing-up cycles (cm-m thick) can be observed within member b and/or member d in many sections (RM2, SI1+2; Figs. 5, 8). Each cycle exhibits a characteristic facies succession, with bioclastic packstones at the base to laminated mudstones and wackestones with intercalated bioturbated horizons in the middle, to gastropod horizons or mudstones with fenestral fabrics at the top (Fig. 8b). Member c, between the cliff-forming members b and d, contains ammonites (section RM2, Fig. 5) and abundant planktic foraminifers (section SI1+2, Fig. 8). A major surface marks locally the top of members b and d, marked by iron crusts/impregnations, vertical burrows and/or reworked pebbles/clasts (sections RM2, SI1+2; Figs. 5, 8). 6.2 Fuheis Formation (Masri 1963) The Fuheis Formation comprises middle Cenomanian deposits. The stratigraphical range is based on calcareous nannofossil zones CC 9-CC 10 and ammonite biozones rhotomagense to jukesbrowneri (Figs. 3, 5, 7, 8). The formation comprises the Karak Limestone Member (KL, Fig. 4) in central and southern sections. Field data exhibit a thickness of the Fuheis Formation from 65m in northern sections (WS, Fig. 1) to 10m in the south of the working area (section SI1+2, Fig. 8).. 29.

(44) Chapter 2 Cenoman-Turonian carbonate platform deposits. Fig. 7: Measured primary section MA3 from the central part of the study area (Wadi Abu Khusheiba, see Fig. 1). Stratigraphic, lithologic and sequence stratigraphic frame presented in left columns. Local ranges of biostratigraphically significant species are indicated on the righthand side. For explanation of symbols, signatures and abbreviations see legend figure 4.. 30.

(45) Chapter 2 Cenoman-Turonian carbonate platform deposits. In the northern part of the study area (see Fig. 1), the formation is predominated by marls and argillaceous and nodular limestones (sections RM2, Fig. 5). In the central area (MA3, Fig. 7) the clay-content increases and organic-rich black shales and bituminous, laminated, argillaceous limestones occur locally. The southern sections (SI1+2, Fig. 8) are characterised by marls and marly limestones. In the entire study area, the Fuheis Formation comprises fossiliferous limestones, locally with ammonites (sections RM2, MA3; Figs. 4, 5, 7), in the lower or middle part of the formation. In the middle or upper part of the formation, well-bedded (thinly laminated, with silty/sandy horizons) limestones occur, locally intercalated with nodular oyster-bearing limestones (section MA3, Fig. 7), which are often rich in monotypic ostracodes. Quartz grains occur in places. These bedded limestones are distinguished as the Karak Limestone Member in the central and southern part of the study area (mentioned above). 6.3 Hummar Formation (Masri 1963) The upper Cenomanian age of the Hummar Formation is indicated by calcareous nannofossil zone CC 10, the guerangeri (ammonite) Zone and occurrences of larger benthic foraminifers (Figs. 4, 7, 8). The thickness of the Hummar Formation decreases from about 50m in the north (section RM4, Fig. 6) to about 10m in southern sections (SI1+2, Fig. 8). In the northern parts (section RM4, Figs. 1, 5), the Hummar Formation consists mainly of cliff-forming argillaceous dolostones and dolomitic limestones. These deposits are characterised by abundant oysters, rudists, and gastropods. Moreover, cyclic stacking patterns are present (Figs. 6, 9c), similar to those of members b and d of the Naur Formation (see above). In the central part of the working area (section MA3, Fig. 7), the formation does not form a clear cliff but consists of marls/shales and intercalated fossiliferous limestones with the same faunal content as observed in northern sections (see above). The Hummar Formation in southern sections (SI1+2, Fig. 8) is predominated by fossiliferous nodular or massive limestones with ammonites. The top of the Hummar Formation is locally characterised by reddish dolomites, iron crusts, and vertical burrows (section RM4, Fig. 6).. 31.

(46) 32. HST. b. Naur Oy. B. TST. a. TST. c. Lower Cenomanian. HST. d. TST. Fuheis. Middle Cenomanian. HST. Hummar. HST. TST. LST. Lower Turonian WL. Shueib. Upper Cenomanian Formation. Substage. Silla SI 1+2 Sequence boundaries. (126m). and. 2m. Systems tracts. ?. Praealveolina cretacea Chrysalidina gradata Schackoina cenomana Whiteinella archaeocretacea Whiteinella aprica. Foraminifers. Eiffellithus turriseiffelii Microrhabdulus decoratus Quadrum gartneri. Calcareous nannofossils. Neolobites vibrayeanus Vascoceras cauvini Thomasites rollandi Choffaticeras quaasi Choffaticeras luciae Fagesia lenticularis. Ammonites. Chapter 2 Cenoman-Turonian carbonate platform deposits. TuJo2. TuJo1. CeJo4. Oy. Oy. CeJo3. CeJo2. Oy. CeJo1. B. Fig. 8: Measured primary section SI1+2 from the southern part of the study area (see Fig. 1). Stratigraphic, lithologic and sequence stratigraphic frame on the left, and local ranges of biostratigraphically significant species on the right. For explanation of symbols, signatures and abbreviations see legend figure 4..