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Environment of deposition of conglomerates from the Silurian of north Galway, Ireland

Published online by Cambridge University Press:  03 November 2011

D. Michael Williams  and
P. D. O'Connor
D. Michael Williams
Affiliation:
Department of Geology, University College, Galway, Republic of Ireland.
P. D. O'Connor
Affiliation:
Department of Geology, University College, Galway, Republic of Ireland.
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Abstract

Conglomerates from the Lettergesh Formation in the Silurian sequence of N Galway, Ireland, demonstrate palaeocurrents from the NE. Fabric studies demonstrate that the conglomerates were emplaced largely by traction currents and not by down-slope sliding or dispersive currents. Stratigraphic relationships demonstrate that the conglomerates were deposited in an environment which was adjacent to fluviatile, shallow-marine and deeper shelf facies at different times. A fan-delta environment of deposition is suggested, which requires a modification of previous Silurian sea-level curves at, or near, the base of the Wenlock.

Keywords

Clasticfabricfan-deltamarinePalaeozoic.
Type
Research Article
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 78 , Issue 3 , 1987 , pp. 129 - 132
Copyright
Copyright © Royal Society of Edinburgh 1987

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