- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
The Wenlock (Silurian) strata on the south shore of Clew bay, northwest Ireland, comprise three groups--Croagh Patrick quartzites, Cregganbaun pelites and calcareous beds, and Knockfadda psammites, altogether some 2,500-5,600 feet in thickness. They are bounded on the north by a fault and are repeated to the south by an overturned syncline (Croagh Patrick syncline). Northwest cross folds are present. The strata have been subjected to a regional metamorphism, not previously described as such, of late Silurian age. Fossil evidence, preserved in a few localities, supports the age determinations.