(NE MEDITERRANEAN) (Two Volumes) SEID
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1 MICROPALAEONTOLOGICAL STUDIES OF RECENT SEDIMENTS FROM THE CILICIA BASIN (N. E. MEDITERRANEAN) (Two Volumes) SEID NOOREDDIN ALAVI, M.Sc. Thesis Submitted for the Degree Doctor of Philosophy of the University of London June, 1980 Department of Geology, Royal School of Mines, Prince Consort Road, London, S.W.7. 2 ABSTRACT The paraecology of dead assemblages of Foraminifera, Ostracoda and planktic molluscs (Pteropoda and Heteropoda) in 142 grab and core- top samples from the surface sediments of the Cilician Basin, recovered at 128 oceanographic stations ranging from a depth of 10 to about 2200m, have been studied. Four samples from the bottom of the Akyatan Lagoon and seven from parts of a piston core from station 1073 were also analysed. Altogether 405 species and varieties of Foraminifera (22 of planktic) and 50 genera of ostracodes have been identified. A list of identified pteropods is also given. Twenty five species of benthic Foraminifera belonging to 23 genera are left in open nomenclature. One ostracod species, tentatively assigned to Phlyctenophora sp., is believed •to be new. Most of the Foraminifera and some ostracodes are illustrated by S.E.M. photographs. Faunal abundance and diversity of the benthic Foraminifera and the abundance of ostracodes and planktic molluscs are mapped and their variation is discussed in terms of the productivity of the surface waters and bottom sediments and the rate of sedimentation. It Is concluded that the planktic/benthic foraminiferal ratio is a more reliable environmental indicator than Ostracoda/benthic Foraminifera ratio. The faunal poverty of the deep-water environment in the basin is discussed in the context of the geological and palaeo-oceanographical history of the E. Mediterranean. The present oceanographic conditions are thought to control the dual system of shelf and basin nutrient supply and recycling in the area. Using the relative abundance of most of the important groups of benthic Foraminifera, six foraminiferal zones are defined: A(9-50m), B(50-15Om), C(150-250m), D(250-500m), E(500-1500m) and F(> 1500m). The rate of sedimentation, chemical and granulometric composition of the sediments, environmental stability and sea-level fluctuations determine the taxonomic composition of foraminiferal biofacies on the shelf. In the bathyal zone (>300m), the assemblages show great homogeneity in their compositions reflecting the uniform environmental conditions below the sill-depth level in the Mediterranean. Redeposition of assemblages and post-mortem processes are discussed and their sedimentological implications are considered. The Foraminifera fauna of the Cilician Basin is believed to be a derivative from the Lusitanian Province which includes some descendents of the ancient stocks of the region. The potential palaeoecological applicability of the conclusions are also briefly discussed. 0 3 Table of Contents Volume One Page Abstract 2 Table of Contents 3 List of illustrations 8 Chapter One: Introduction, Materials and Methods 11 A) Introduction 11 B) Materials 12 C) Method of Study 12 Acknowledgements 15 Chapter Two: Physiography and Geology of the Cilician Basin Area 16 A) Bathymetry 16 B) Climate 16 C) Geological Settings of the Cilician Basin 17 C1)Structure 17 C2)Stratigraphy 18 Chapter Three: Oceanography of the Northeastern Mediterranean 19 A) Palaeo-oceanographic Background 19 B) Inshore Currents and Turbulence 20 C) Offshore Water Masses in the N.E. Mediterranean 21 D) Surface and Intermediate Levels Currents 23 E) Biological and Chemical Properties of the Eastern 24 Mediterranean Water Masses El ) Biological Properties 24 E2 ) Chemical Properties 25 Chapter Four: Some Gross Microfaunal Parameters 26 A) Planktic/Benthic Foraminiferal Ratio 26 B) Abundance Distribution of Shells of Pteropoda and 29 Heteropoda C) Abundance Distribution of Tests of Benthic Foraminifera 30 D) Abundance Distribution of Ostracodes and the Ostracoda/ 35 B. Foraminiferal Ratio • 4 Page E) The Distribution of the Relative Abundances of Arenaceous, Porcellaneous and Hyaline Benthic Foraminifera 39 F) Diversity of the Benthic Foraminiferal Assemblages 42 Chapter Five: Benthic Foraminiferal Biofacies and their 46 Environmental Interpretation I - Sublittoral Zone 47 A - The Inner Shelf Zone 47 B - The Middle Shelf Zone 56 C - The Outer Shelf Zone 66 Distribution of the Relict Benthic Foraminiferal Biofacies on the Shelf of Seyhan and its Relation to the Post-Glacial Rise of the Sea-Level 72 II-The Bathyal Zone 77 Bathymetric Distribution of Bathyal Species of Benthic Foraminifera in the Cilician Basin - A Comparison With Other Areas in the Atlanto-Mediterranean Region 82 Chapter Six: Zoogeographical Aspects of the Cilician Basin 87 Foraminiferal Fauna and Post-depositional Modifications of the Assemblages A) Biogeography and Faunal Affinity of the Cilician Basin Benthic Foraminifera Fauna 87 B) Redeposition of Foraminiferal Tests in the Cilician Basin and its Sedimentological Implications 90 C) Planktonic Foraminiferal and Molluscan Fauna of the Cilician Basin 99 C1)Faunal Background 99 C2)Taxonomic Composition of Assemblages of Planktonic Foraminifera and Pteropoda in the Cilician Basin and its Environmental Implications 101 C3)Abundance Distribution of Various Species of Planktonic Foraminifera and their Depositional Implications 104 Chapter Seven: Main Conclusions and Palaeoecological 108 Applications References 113 5 Volume Two Page Appendix One: Systematic Palaeontology 1 Foraminiferida Eichwald 1 Allogromiidae 1 Astrorhizidae 1 Saccaminidae 2 Ammodiscidae 3 Hormosinidae 4 Lituolidae 5 Textulariidae 7 Trochamminidae 9 Ataxophragmiidae 10 Fisherinidae 12 Nubeculariidae 13 Miliolidae 16 Soritidae 32 Nodosariidae 33 Polymorphinidae 38 Glandulinidae 39 Turrilinidae 41 Sphaeroidinidae 41 Bolivinitidae 42 Islandiellidae 45 Buliminidae 45 Uvigerinidae 48 Discorbidae 49 Glabratellidae 52 Siphoninidae 53 Asterigerinidae 53 Spirillinidae 55 Rotalliidae 56 Elphidiidae 57 Nummulitidae 61 Hant kenini dae 61 Globorotalidae 61 Globigerinidae 63 Eponididae 66 • 6 Page Amphisteginidae 67 Cibicididae 67 Planorbulinidae 68 Acervulinidae 69 Cymbaloporidae 69 Homotrematidae 69 Caucasinidae 69 Loxostomidae 70 Cassidulinidae 71 Nonionidae 71 Alabaminidae 74 Osangulariidae 74 Anomalinidae 75 Ceratobuliminidae 75 Robertini.dae 76 Ostracoda Latreille (generic list) 77 Acantocythereis 77 Aglaiocypris? sP. 77 Argilloecia spp. 77 Aurila sm. 77 "Bairdia" ses. 77 Basslerites es.s 78 Bosquetina es.s 78 ses. Buntonia 78 Bythocythere? tetrapteron 78 Callistocythere spp. 78 Candona sg. 78 Carinocythereis spp. 78 Cluthia keiji 79 Costa s p. 79 Cyprideis so. 79 Cytherella ses. 79 Cytherelloidea sordida 79 Cytheretta sl. 79 Cytheropteron spp. 79 Cytheridea sg. 8o Eucytherura spp. 8o 7 Page Falunia spp. 80 Hemicytherura spp. 8p Henryhowella sPp. 8p Heterocythereis lip. 8o Ilyocypris sp. 8o Hemicytherura (Kangaria) 8o "Krithe" spp. 81 Leptocythere spR. 81 Loculicytheretta pavonia (Brady) 81 Loxochonca spp. 81 Loxocythere es.s 81 Monoceratina sz. 81 Neocythereis ses. 81 Occultocythereis lineata 82 Paracytheridea spp. 82 Paradoxostoma sp.. 82 Pedicythere phyrne 82 "P." testella 82 Phlyctenophora sa. 82 Phyctocythere sp. 82 Polycope spp. 83 Pontocythere es.s 83 Propontocypris ses. 83 Pseudocythere spp. 83 Pterygocythereis sm. 83 Quadracythere prava 83 Semicytherura ses. 83 Urocythereis ses,. 83 Verrucocythereis sp.. 84 Xestoleberis ses. 84 Appendix Two: Locations, Depths and Lithology of the 85 Quantitatively Studied samples 1972 Collection 85 1974 Collection 87 1977 Collection 88 • 8 List of Illustrations Charts (in pocket). Chart One, General Bathymetry of Cilicia Plateau Area. Chart Two, Distribution of Samples and their Relation to the Bathymetry of the Area. Chart Three, Simplified Geology and Drainage Systems of the Coastal Areas around Cilicia Plateau Figures. Fig. 1, Surface Salinity. Fig. 2, Surface Temperature. Fig. 3, Bottom Water Temperature. Fig. 4, Secchi-disc Values. Fig. 5, Temperature, Salinity and Oxygen Profiles (Sept., 1968). Fig. 6, Temperature, Salinity and Oxygen Profiles for Other Seasons. Fig. 7, Phosphorous, Nitrogen and Silicon Concentration Variation with Depth. Fig. 8a, Surface Layer Currents. Fig. 8b, Intermediate Level Currents. Fig. 9, Distribution of Hydrographic Stations Used to Plot the Profiles in Figs. 5-7. Fig. 10, Water Transparency in Metres. Fig. 11, Planktonic Foraminiferal Percentage in > 7511. Fraction. Fig. 12, Planktonic Foraminiferal Percentage in >25011 Fraction. Fig. 12a, Concentration of Planktonic Forams. (specimens/gr.sed.). Fig. 13, Ranges of Variation in the Percentages of Planktonic Forams from Two Samples at the Same Station. Fig. 14, Differential Relative Abundance of Planktonic Tests in Coarser and Finer than 25011 Fractions. Fig. 15, Contentration of Pteropods and Heteropods. Fig. 16, Estimated Percentage of Displaced Tests of Benthic Foraminifera. Fig. 17, Weight Percentage of > 75p. Residue. Fig. 18, Foraminiferal Concentration Factor. Fig. 19, Calculated Number of Benthic Foraminiferal Tests per gram of Sediments. Fig. 19a, Benthic Foraminiferal Number vs. Depth on the Shelf and Slope of Seyhan. Fig. 20, Concentration of Ostracods. • 9 Fig. 20a, Ostracoda/B. Foraminiferal Ratio. Fig. 21, Percentage Distribution of Arenaceous Foraminifera. Fig. 22, Percentage Distribution of Miliolids. Fig. 23, Percentage Distribution of Hyaline Taxa. Fig. 24, Benthic Foraminiferal Diversity Indices (a). Fig. 25, Proposed Recent Benthic Foraminiferal Biofacies in the Cilician Basin.