Oxford Clay Invertebrate confusion

[DE&i]

COELENTERATES

 

Class ANTHOZOA

 

Anthozoa are represented in the Oxford Clay by a single species of the ahermatypic coral Trochocyathus. However, when it occurs, it is relatively abundant. The general absence of corals in the Oxford Clay Sea may be a consequence of high sediment input, and possibly reduced light levels. Trochocyathus today is found in waters greater than 30 meters deep.

 

 

Described: Small, solitary cup coral, outline circular, depressed, slightly conical. Septa prominent on theca. Columella fasiciculate.

 

 

Remarks: Common in the Middle Oxford Clay, where it rarely reaches more than one centimetre diameter.

 

 

The description for these corals above is certainly correct as quoted from the most excellent Fossils of the Oxford Clay book.

A friend of mine found quite a few of them in 1985. And today gave me a few with a label stating they “Derived from the Middle Oxford Clay, Glacial Drift”

 

 

It’s the “Glacial Drift” wording that has me confused , would anyone have any suggestions please. @oxford clay keith 

 

 

 

 

Edited December 13, 2016 by DarrenElliot
Typo

[TqB]

It just means they're from boulder clay or associated gravels, derived and transported from Oxford Clay bedrock.

[Kosmoceras]

A couple of years ago on a fieldtrip to a quarry around Bedfordshire I saw and collected from an exposure of glacial deposits full of derived Oxford Clay fossils. I would have thought it is something like this he is referring to.

[DE&i]

That makes sense, just the answers I was looking for. I think the confusion stemmed from the conversation we had about these fossils. And the phrase " glacial erratics " kept popping up. Which clearly they are not.

[abyssunder]

Nice little corals.

 

Maybe this document explains the phenomenon, also there is an illustrated specimen of Trochocyathus magnevillianus Michelin, among other erratic macrofossils.

 

Etienne, J.L. 2001. Middle Pleistocene glacigenic sediments at Holwell, Hertfordshire: a record of a fluctuating Anglian ice margin. Proceedings of the Geologists' Association, 112 (4), 361-371.

 

Erratum

 

 

[abyssunder]

Also, if someone is interested in, here is Milne Edwards and Jules Haime description in
A Monograph Of The British Fossil Corals. 1851. Second Part. Corals From The Oolitic Limestones. Chapter XI. Corals From The Inferior Oolite. Page 126-127 - related to Trochocyathus magnevillianus.

 

 

 

[Ridgehiker]

That's such a nice publication.  I also have a copy.  The older paleontology books are as much a work of art as they are science.

[DE&i]

Thank you @abyssunder and yes @Canadawest I couldn't agree more. And rather spooky timing. As my son and I were looking at some Lincolnshire limestone for coral's last week. This particular exposure is part of the Inferior Oolite Group of the (Bajocian) Middle Jurassic strata of eastern England.We were unsuccessful , but the fresh air was free, and good to get out and about.