THE GAULT CLAY (LOWER CRETACEOUS, MIDDLE AND UPPER ALBIAN) AT COPT POINT, FOLKESTONE, KENT

The Gault Clay at Folkestone first appears at the top of the sea cliff beneath the East Cliff Pavilion in Wear Bay Road where it sits conformably on the Folkestone Beds and extends eastwards for around one kilometre, declining gradually to the foreshore in East Wear Bay where it is overlain by the lower chalk.

The Gault is divided into Upper and Lower, equating to the Middle and Upper Albian stages respectively. The Lower Albian is represented by the Folkestone Beds and comprises the uppermost Lower Greensand. The Gault is further subdivided into thirteen beds (Beds I to VII in the lower Gault and VIII to XIII in the Upper).

The fossils of the Gault provide a glimpse of life in a fairly shallow muddy-bottomed marine sea which covered most of southern and eastern England towards the end of the Lower Cretaceous epoch between 104 and 96 million years ago before the chalk was formed.

The formation is best known for its beautifully preserved molluscs (coiled and uncoiled ammonites, and bivalves and gastropods); bony fish remains, shark teeth and vertebrae; crab and lobster carapaces; and for its extensive micro-fauna. Other commonly found fossils include belemnite guards, scaphopods (tusk shells), solitary corals, serpulid worms and goose-barnacle valves. Nautiloid cephalopods, sea urchins and brachiopods are relatively uncommon. Teeth and vertebrae of large sea-going reptiles are occasionally found but evidence of life on land is limited to drift-wood, the remains of a few pterodactyls and very rare pine-cones.

Bulk clay sampling and processing is a highly effective method of collecting micro- fossils. Washed residues can contain exquisitely preserved foraminifera, ostracods, micro-gastropods and bivalves, fish and shark teeth, fish otoliths, parts of star fish, brittle and feather starfish, and of fixed and floating crinoids.

Gault fossils can be collected in-situ (although it is undesirable to dig in the cliffs), and from fallen blocks of clay at the foot of the sea cliffs or washed out between rocks and boulders on the beach. Occasionally outcrops of clay offering excellent collecting opportunities are exposed on the foreshore in East Wear Bay after beach sand has been removed following winter storms. Fossils from the Lower Greensand can be collected from the foreshore reef.

Care should always be taken when collecting on or below the sea cliffs and only when tidal conditions permit.

Classic type section of the Gault clay, Copt Point, Folkestone Kent UK Zonal, Subzonal and typical Ammonites and Belemnite (not to scale)

Hysteroceras orbignyi “ "cristatum" to "auritus" subzone Neohibolites minimus (ubiquitous) Euhoplites alphalautus “varicosum” to "auritus" subzones

Dipoloceras cristatum “cristatum” subzone

Anahoplites planus “dentatus" to "inflatum” zones Anahoplites daviesi “daviesi” subzone

Euhoplites lautus Euhoplites nitidus “lautus/nitidus” to “lautus/nitidus” to "cristatum" subzone "daviesi" subzones Dimorphoplites biplicatus “subdelaruei" - "cristatum” subzones

Euhoplites loricatus “intermedius” to "lautus nitidus" Anahoplites praecox “intermedius” subzone

Mojsisoviczia spinulosum "subdelaruei" subzone

Hoplites bennettianus Lyelliceras lyelli Hoplites dentatus “bennettianus” subzone “lyelli” subzone “dentatus” zone Gault Biostratigraphical Indicator Fossils

x 1 x 1 x 1 Fig 1 Fig 3 x 1

Fig 4 Fig 2

x 1 x 1 x 8

Fig 5

x 3 Fig 6 Fig 8 Fig 7

Fig 10 x 0.5 x 1.5 x 1

x 0.5

Fig 9

Fig 12 Fig 11

Fig 14 Fig 13 x 7 x 5

x 4

Fig 15 Fig 16

Bivalves Fig 1 Pectinucula pectinata; Fig 2: Birostrina concentrica; Fig 3: Birostrina sulcata; Gastropods Fig 4 Apporhais; Fig 5 Natica Crustacea: Fig 6 Cirripede tegrum: Cretiscalpellum; Fig 7 Crab Notopocorystes stokesii Fig 8 Ostracoda: Fig 9 Echinoid Hemiaster sp; Fig 10 Crinoid ossicles; Isocrinus sp : Fig 11 Scaphopod Dentalium decussatum; Fig 12 Heteromorph ammonite: Hamites sp ; Fig 13 Foraminifida various Nodosariid forams; Fig 14: Shark Tooth Synechodus sp; Fig 15 Solitary Coral: Discocyathus fittoni; Fig 16 Bony fish otolith:

USEFUL (AND INEXPENSIVE) GUIDES TO IDENTIFICATION OF FOSSILS FOUND IN KENT

Title: FOSSILS (Eyewitness Handbooks) Author: Cyril Walker and David Ward Published by: 1992 by Dorling Kindersley ISBN: Hardback: 0-7513-1004-2 Flexibound: 0-86318-921-0 Price: £16.99 (Hardback): Flexibound: Not known (around £12.00)

Title: FOSSIL PLANTS OF THE LONDON CLAY (Field Guide to Fossils No. 1) Author: Margaret Collinson Published by: 1983 by The Palaeontological Association London ISBN: 0-901702-26-9 Price: £7.95

Title: FOSSILS OF THE CHALK (Field Guide to Fossils No. 2) Compiled by: Ellis Owen Published by: 1987 by The Palaeontological Association London ISBN: 0-901702-36-6 Price: £11.50

Title: AN ILLUSTRATED GUIDE TO THE BRITISH MIDDLE EOCENE VERTEBRATES Author: David Kemp, Liz Kemp and David Ward Published by: David Ward - London October 1990 ISBN: None Price: Around £8.00

Title: BRITISH CAENOZOIC FOSSILS (fifth edition) Author: The Natural History Museum Published by: HMSO ISBN: 0-11-310024-8 Price: £7.95

Title: BRITISH MESOZOIC FOSSILS (fifth edition) Author: The Natural History Museum Published by: HMSO ISBN: 0-11-310025-6 Price: £8.50

Title: BRITISH PALAEOZOIC FOSSILS (fourth edition) Author: The Natural History Museum Published by: HMSO ISBN: 0-11-310026-4 Price: £9.95

Title: UNDERSTANDING FOSSILS (An Introduction to Invertebrate Palaeontology) Author: Peter Doyle Published by: 1995 John Wiley & Sons ISBN: 0-471-96351-8 Price: Not stated, but around £18.00

Title: MICROFOSSILS Author: M.D. Brasier Published by: 1980 George Allen & Unwin (fourth impression) ISBN: Hardback: 0-04-562001-6 Paperback: 0-04-562002-4 Price: Not stated, but Paperback around £13.00

Title: MIDDLE ALBIAN STRATIGRAPHY IN THE ANGLO PARIS BASIN Author: H.G. Owen Published by: 1971 - Bulletin of the British Museum (Natural History) ISBN: None given (Supplement No 8 of the Geological (Palaeontological) Series Price: Not stated. Can be purchased for around £12.00