RT Journal Article
SR Electronic
T1 Silurian turbidite provenance and the closure of Iapetus
JF Journal of the Geological Society
JO Journal of the Geological Society
FD Geological Society of London
SP 349
OP 357
DO 10.1144/gsjgs.149.3.0349
VO 149
IS 3
A1 WILLIAMS, D. M.
A1 O’CONNOR, P. D.
A1 MENUGE, J.
YR 1992
UL http://jgs.lyellcollection.org/content/149/3/349.abstract
AB Subduction of Iapetus crust during the Caledonian orogeny has been seen by some authors as terminating at the end of Ordovician times and by others as continuing through the Silurian. We present petrological and chemical data which support a coeval arc origin for detritus in the Lettergesh Formation (Silurian), western Ireland. The arc, based on continental crust, lay to the north of the present outcrops of this formation, along the Laurentian margin of Iapetus, implying active oceanic subduction in the Silurian. This subduction may have been followed by some continental underplating around the middle of the Wenlock giving rise to a successor basin in Ireland and Scotland.