AN ANALYSIS OF THE MICROFAUNA AND MICROFLORA OF THE UPPER EOCENE OF THE HAMPSHIRE BASIN By Martin Simeon Norvick Thesis Submitted for the Degree of Doctor of Philosophy at the University of London. Abstract The succession of the Upper Bracklesham and Barton beds of Hampshire i! discussed in a lithostratigraphic context. Compilations from surface sections and borehole data enable lithological correlations to be made, based on the cyclic pattern of lithofacies. The areal distribution and variations in thickness of lithological units are elucidated and the local palaeogeography is reconstructed. Stratigraphic usage of planktonic and larger Foraminiferida in the North West European Upper Eocene is reviewed,, A detailed study of the Nummulites shows the presence of seven morphological units and their distribution as local stratigraphic markers is evaluated. The total microfauna and microflora of the Barton Beds from Christchurch Bay and Alum Bay is examined quantitatively and the percentage distributions of Foraminiferida, Ostracoda and ivIollusca are presented graphically. In addition the occurrence of Dinoflagellat,, and Tasmanitid cysts, Angiosperm seeds, Echinoderm, Sponge, Bryozoan, Annelid and Vertebrate remains are studied qualitatively. The variatic..1 in distribution of species and larger units is used to provide a biofac' - zonation of the Barton Beds. Two cycles of sedimentation are recognised and and the two sections are compared. The total fauna and flora is classified into 459 indigenous taxonomic and organ groups. Meroplankton and Holothuroid ossicles are recorded for the first time from the Barton Beds and !!3 species are described and illustrated. 99 species of Foraminiferida, 34 of Ostracoda, 168 species and groups of Mollusca and 28 species of smaller phyla are also described and the majority figured. Finally 26 Echinoderm and 61 Vertebrate organ groups are recorded° ********** LIST OF CONTENTS ?age. Abstract .4r 6646 2. Section 1 INTRODUCTION, METHODS and LOCALITIES ,,teeoeis," 1:1 Introduction 7. 1:1:1 The Problem 7. 1:1:2 Samples, depositories and taxonomy 7. 1:1:3 Acknowledgements 9. 1:2 Methods 11. 1:3 Sample Localities 130 1:3:1 Christchurch Bay 13. 1:3:2 Alum Bay 17. 1:3:3 Other Sections 180 Section 2 UPPER EOCENE STRATIGRAPHY 25. 2:1 The Problem 25. 2:2 English Upper Eocene Lithostratia,raphv 000000 250 2:2:1 Previous Work 25, 2:2:2 Lithological Correlations 23. 2:2:3 Conclusions on English Upper Eocene Li thostratigraphy 38. 2:3 Upper Eocene Palaeontology 43. 2:3:1 The Planktonic Foraminiferida 43. 2:3:2 The Larger Foraminiferida (excluding the Nummulites) 45. 2:3:3 The Nummulites . 51. 2:3:4 Stratigraphic Conclusions 65. Section 3 SYNTHESIS OF BARTON BEDS FAUNA and FLORA 68. 3:1 Introduction 68. 3:1:1 Methods 69, 3:1:2 Limits of Accuracy 70. 3:1:3 Presentation and Interpretation 750 3:2 Distribution of the Major Groups 77, 3:2:1 Lithology and grain size distribution 77, 4. Section 3:2:2 Fragment and whole group analysis 78. 3:2:3 The Marine Algae 80. 3:2:4 The Foraminiferida 3:2:5 The Ostracoda 86. 3:2:6 The Mollusca 87. 3:2:7 The Eryozoa 85. 3:2:8 Small groups and others 89. 3:2:9 Reworked elements 90. 3:3 Conclusions 91. Section 4 TAXONOMY 93. 4:1 Algae and Incertae Sedis 93, 4:1:1 DinoflagellatPs 93e 4:1:2 Tasmanitids 134. 4:1:3 Incertae Sedis 144. • 4:2 Foraminiferida 147. 4:3 Small Groups 225,, 4:3:1 Angiosperm Seeds 225,, 4:3:2 Porifera 226. 4:3:3 Coelenterata 227. 4:3:4 Annelida 227. 4:3:5 Arthropoda (excluding Ostracoda) 230. • 4:4 Bryozoa 232. 4:5 Ostracoda 240. 4:6 Mollusca 268. 4:6:1 Pelecypoda 269. 4:6:2 Scaphopoda 290. 4:6:3 Gastropoda 291,, 4:6:4 Cephalopoda 337. 4:7 Echinodermata 338. 4:7:1 Asteroid Ossicles 340. 4:7:2 Crinoid Ossicles 343 343. 4:7:3 Echinoid Ossicles ••• Section 4:7:4 Ophiuiroid Ossicles 345, 4:7:5 riolothuroid Ossicles 348. 4:8 Vertobrata 350. 4:8:1 Vertebrate Bones, Scales and Teeth 350. 4:8:2 Teleost Otoliths 357. Section 5 BI3LIOGRAPHY 366. Section 6 PLATES 393. ********** 64 LIST OF TABLES 1. Barton Beds of Christchurch Bay. 2. Barton Beds of Alum Bay. 3. Lithological Correlations in the Hampshire Upper Eocene:Southern Series. 4. Lithological Correlations In the Hampshire Upper Eocene:Northern Series. 5. Fragment and grain size analyses. 6. Total ranges of Barton Beds Foraminiferida and Ostracoda in the Falaeo- gene. 7. Total ranges of Foraminiferida in the Barton Beds of Christchurch Bay. 8. Total ranges of Foraminiferida in the Barton Beds of Alum Bay. 9. Percentage distribution of Foraminiferida in the 60-200 Fraction: Christchurch Bay. 10.Pbrcentage distribution of Foraminiferida in the 60-200 Fraction:Alum Bay. 11.Foraminiferal ratios and diversity. 12.Total ranges of Ostracoda in the Barton Beds. 13.Percentage distribution of Ostracoda in the 60-30 Fraction Christchurch Bay- 144 Percentage distribution of Ostracoda in the 60-30 Fraction:Alum Bay. 15.Total ranges of Yollusca in the Barton Beds of Christchurch Day. 16.Total ranges of Mollusca in the Barton Beds of Alum Bay. 17.Percentage distribution of Pelecypoda in the 10-30 Fraction:Christchurch Bay. 13. Percentage distribution of Pelecypoda in the 10-30 Fraction:Alum Bay. 19.Percentage distribution of Gastropoda and Scaphopoda in the 10-30 Fraction: Christchurch Bay. 20.Percentage distribution of Gastropoda and Scaphopoda in the 10-30 Fraction. Alum Bay. 21. Total ranges and ratios of Microplankton in the Barton Beds of Christchurci. Bay., 22. Total ranges and ratios of Microplankton in the Barton Beds of Alum Day. 23. Ranges of small groups in the Barton Beds. 24. Ranges of Echinoderm ossicles in the Barton Beds. 25. Ranges of Vertebrate remains in the Barton Beds of Christchurch Bay. 26. Ranges of Vertebrate remains in the Barton Beds of Alum Bay. 27. Biofacies zonation of the Barton Beds: Christchurch Bay. 28. Biofacies zonation of the Barton Beds: Alum Day. 29. Biofacies correlations in the Barton Beds. 7. Section 1 INTRODUCTION.METHODS and LOCALITIES Section 1:1 INTRODUCTION 1:41.. The Problem This project was originally devised to test the feasinnt7 o a quantitative total m4crofaunal and m4crofloral study, to apply it to problems of-palaeoecology'and stratigraphy, and to devise new methods of correlation. The Barton Beds and Headon Beds of Hampshire were initially chosen to provide a,model for such a study but the inclusion of the latter division had to be abandoned in view of the practically doubled weight of taxonomic work-involved. -The revised thesis falls along-two main lines of research, namely the total faunal and-the stratigraphical aspects of the Upper Eocene. Quantita- tivemicrofaunal and microfaunal investigation is concentrated on the marine -parts of- the Barton. Beds cycle of sedimentation (see Fig.2). All the evid- ence-from dry washed residues-is dealt with-but palynological aspects had to be curtailed awing to-the lack of time. This investigation is-associated with-biofacies and palaeoecological interpretations (Section 3). Any such-work demands a detailed examination of the stratigraphy. The upper - part - of the Eocene (see Fig.2) is studiedin.a lithostratigraphical context. "Classical" biostratigraphy (i.e. use of evolving lineages for zonation.and correlation) is applied in the case of one group of fossils, namely the Nummulites (Section 2). 1:1:2 Samples, Depositories and Taxonomy Two main sections were sampled at close intervals for the quantitative aspects-of the project, namely Christchurch.Bay (129 samples) and Alum Bay (113 samples). In addition 40 samples from other English Palaeogene localities (London Clay to. Middle Oligocene) and 5 samples from the French .Paris Basin localities were examined for comparative taxonomic purposes* All are assigned Imperial College Micropalaeontology sample numbers in the series 6481-7199 and residues are deposited in. the Micropalaeontology Laboratory, Imperial College of Science and Technology, London, S.W.7. This study involved a. large amount of taxonomic work.. A total of 459 indigenous units (species, subspecies, varieties and "organ groups") Studley Wood 0 0 Bramshaw Huntingbridge 0 ease OBrook of S. ham 7.er tiar.y +Lyndhurst 0 Poulnor 0 Fa ey NEW FOREST 2hriilm+ Tr. Tu. Lee-on-So n ortsm • Lymington 50 ENE Seise Christchurch we, Bay Hamstea Hengistbury Head Colwell Bay Headon Hill Whitecliff Alum Bay, ISLE OF WIGHT Bay figure 1 0 miles 10 LOCATION OF SECTIONS IN SOUTH HAMPSHIRE 0 kms 1,0 & THE ISLE OF WIGHT 96 belonging to 10 major groups are described and/or figured from the Barton Beds (see Fig.3). This demanded a less exhaustive treatment of certain groups (particularly Mollusca and Ostracoda) than would have been preferred, especially as some groups had to be studied from first principles (Dinoflagellates, Ostracoda) and some required a new approach (Echinoderms, Vertebrate teeth). No new names have been proposed in view of this less rigorous application and undescribed or unidentifiable units are lefi: as numbers. All figured specimens are deposited in the Micropalaeontology Laboratory, Imperial College. 1:1:3 Acknowledgements The author is deeply indebted to Yr. D. J. Carter for supervision, encouragement and advice. The main part was untlzkii:?. at the Department of Geology, Imperial College of Science and Technelogy, while on a Natural Environmental Research Council Studentship. It was completed while holding a Demonstratorship at University Collega;London, and the author is grateful to Professor D. T. Donovan for his provision of equipment and facilities. Particular thanks is also due to Dr., Marjorie Muir for her encourage- ment throughout the project, for her advice on all aspects of the Dino- flagellate and Tasmanitid work and for her considerable help with the Stereoscan illustrations, Acknowledgement is gratefully given to Professor D.V.Ager, Mr.D.CurrY, Mr.Fowler, Mr.A.King, Yr.C.King and Mr.F.C.Stinton for many fruitful discussions and the provision of samples and specimens, also to Mr.Castell and to Dr.