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The Late Triassic Blue Anchor Formation and the initial Rhaetian marine transgression in south-west Britain

Published online by Cambridge University Press:  01 May 2009

M. J. Mayall
M. J. Mayall
Affiliation:
The British Petroleum Company Limited, Britannic House, Moor Lane, London EC27 9BU.
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Summary

The Blue Anchor Formation of the Upper Trias in south-west Britain is divided into two members. The lower (Rydon Member) was deposited in an evaporitic lacustrine environment whilst the upper (Williton Member) was deposited in a shallow marine environment and represents the initial marine transgression into south-west Britain late in the Triassic Period. Sedimentological and clay mineralogical evidence indicates that the Williton Member is bounded by erosional disconformities and, at present, can only be positively recognised in North Somerset.

Type
Articles
Information
Geological Magazine , Volume 118 , Issue 4 , July 1981 , pp. 377 - 384
Copyright
Copyright © Cambridge University Press 1981

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