Chalk Seas

6th August 2008

Chalks were widely deposited during the Cretaceous. They represent the accumulation of marine algae (coccoliths) in marine environments that received very little clastic input from the continents.

I remember collecting urchins and corals from the chalk at Dover whilst waiting for the ferry to France. Prepared with a toothbrush and water these revealed amazingly fine details.

Here is a small collection of fossils from Cretaceous chalk, mainly from the UK, but with others from Kansas and Lebanon (in a laminated sub-lithographic limestone).

Micraster cortestudinarium 4 cm Chalk, Turonian. Charnage Quarry, Mere, Wiltshire.	Offaster pilula, 3 cm complete echinoid. Campanian, O. Pilula Zone, Hursley, Hampshire, UK.	Holaster subglobosus. 38 mm. Cenomanian. Shakespear cliff, West of Dover, Kent, UK.	Gautheria radiata 24 mm, White Chalk of Beachy Head, Kent, UK.
Bourgueticrinus hureae. Upper Chalk, Turonian, Upper Cretaceous. Pegwell Bay, Kent, England. 14 mm calyx and stem.	Schloenbachia varians, 39 mm ammonite. Lower Chalk, Lower Cenomanian, Cretaceous, Evershot, Dorset.	Scaphites equalis, 27 mm long. Chalk, Middle Cenomanian, Upper Cretaceous. Uplyme, Dorset, UK.	Nautilus sp, 90 mm complete nautiloid, Lower Chalk, Shepwick Quarry, Uplyme, Dorset, UK.
Neohibolites minimus. 3 cm and 2 cm individuals. Gault Clay, Albian, Lower Cretaceous. Heath and Reach, Bedforshire.	Gibbithyris cf media, 37 mm shell. Upper Albian, Hunstanton, Norfolk.	Terebratula sp. 25 mm. Lower Chalk. Capel-le-Ferne, Folkestone, Kent.	Porosphaera globularis. 10 to 15 mm. Upper Chalk. Pegwell Bay, Ramsgate, Kent, UK.
Parasmilia fittoni, 27 mm coral. Upper Chalk, Campanian. East Harnham, Wiltshire.	Hoploparia longimana. Upper Greensand, Aptian, Lower Cretaceous. Charmouth, near Lyme Regis, Dorset, England. 15 cm excellent with limbs preserved.	Ptychodus sp. crushing tooth of a shark or ray, 24 mm. Chalk, Dover, Kent, England.	Crinoid, Uintacrinus socialis, 6cm, Niobrara Chalk, Kansas, USA.
10.5 cm Antedon pinnulata comatulid crinoid. Cenomanian, Cretaceous. Hjoula Lebanon.	Mantis shrimp, Pseudosculda, 35 mm from the Cenomanian of Lebanon.	Crab, Geryon, 3 cm from the Cenomanian of Lebanon.	Fabulously rare Galatheoid decapod “squat lobster”. Mid Cenomanian, Hajoula, Lebanon. Slab is 11 cm tall.
Teuthid, 7 cm from the Cenomanian of Lebanon.	Teuthid, 6 cm from the Cenomanian of Lebanon.	Juvenile shark, 14 cm from the Cenomanian of Lebanon.	Cyclobatis major, 17 cm long. Mid Cretaceous, Mid Cenomanian (~93 mya). Hajoula, Lebanon.