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Detrital Portland chert and limestone in the Upper Purbeck Beds at Friar Waddon, Dorset

Published online by Cambridge University Press:  01 May 2009

Ian M. West
Affiliation:
Department of Geology, The University, Southampton.
Malcolm J. Hooper
Affiliation:
Campbell Chibougamou Mines Ltd., Chibougamou, Quebec.

Summary

Pebbles of derived Portland chert and limestone have been found in the Upper Purbeck Beds at Friar Waddon, Dorset. The Unio Bed at this locality is of unusual lithology with derived phosphatic fossils and with fish teeth. The presence of this chert in the Upper Purbeck Beds and its apparent absence in Lower Purbeck pebble beds suggests that a major phase of silicification in the Portland Stone took place at about Middle Purbeck times. Furthermore, erosion of the Portland Beds occurred in the Weymouth region, probably on the crest of the Weymouth anticline, during Upper Purbeck times.

Type
Articles
Copyright
Copyright © Cambridge University Press 1969

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References

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