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The significance of toolmarks on a Silurian erosional furrow

Published online by Cambridge University Press:  01 May 2009

P. H. Bridges
P. H. Bridges
Affiliation:
Sedimentology Research Laboratory, The University, Whiteknights, Reading
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Summary

The toolmark pattern on an erosional furrow from the Llandovery shelf sequence in the Welsh Borderland indicates that there was:— (i) local helical flow within the furrow similar to that found in sinuous alluvial streams and (ii) a moderately powerful current which moved towards the shore. Erosion by a shallow water turbidity current or storm surge tidal ebb flow therefore seems unlikely. A flood tidal current super-imposed on storm wave oscillatory disturbance of the sea-floor provides a possible mechanism.

Type
Articles
Information
Geological Magazine , Volume 109 , Issue 5 , September 1972 , pp. 405 - 410
Copyright
Copyright © Cambridge University Press 1972

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