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The Wenlock sediments of north-west Galway, Ireland.

Published online by Cambridge University Press:  01 May 2009

M. G. Laird  and
W. S. McKerrow
M. G. Laird
Affiliation:
New Zealand Geological Survey, P.O. Box 90, Greymouth, New Zealand
W. S. McKerrow
Affiliation:
Dept. of Geology and Mineralogy, University of Oxford, Parks Road, Oxford
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Summary

This work describes the Wenlock sedimentary sequences south of Killary Harbour where the fullest successions in north-west Galway are exposed; much of the Upper Silurian in the east (Joyces Country) has been removed by erosion.

The Wenlock beds (the Upper Owenduff and Killary Harbour Groups) rest on shallow marine and continental sediments (the Lower Owenduff Group) of Upper Llandovery (C5–6) age. Conglomerates near the base of the Wenlock are followed by 1,500 m of sandstones, which are mostly turbidites and which contain Middle Wenlock graptolites. These basin deposits are succeeded by a transitional sequence of rise, slope and shelf clastics, also of Middle Wenlock age. The youngest Silurian beds exposed are 800 m of red lagoonal deposits with Lingula.

During Wenlock times, the sediment supply to north-west Galway was mainly from the north and north-west. This observation fits well with the regional picture which places Galway near the north-west margin of a Silurian basin which extended eastwards across Ireland.

Type
Articles
Information
Geological Magazine , Volume 107 , Issue 4 , July 1970 , pp. 297 - 317
Copyright
Copyright © Cambridge University Press 1970

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References

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