PROVENANCE OF LATE ASHGILL (HIRNANTIAN) FINE-GRAINED SEDIMENTS AND PEBBLES IN THE WELSH BASIN - A ND AND SR ISOTOPE STUDY

Authors
LENG MJ EVANS JA
Citation
Mj. Leng et Ja. Evans, PROVENANCE OF LATE ASHGILL (HIRNANTIAN) FINE-GRAINED SEDIMENTS AND PEBBLES IN THE WELSH BASIN - A ND AND SR ISOTOPE STUDY, Geological journal, 29(1), 1994, pp. 1-9
Citations number
19
Categorie Soggetti
Geosciences, Interdisciplinary
Journal title
Geological journal → ACNP
ISSN journal
00721050
Volume
29
Issue
1
Year of publication
1994
Pages
1 - 9
Database
ISI
SICI code
0072-1050(1994)29:1<1:POLA(F>2.0.ZU;2-Z
Abstract
The isotope characteristics of interbedded fine-grained sedimentary ro cks and pebbles from an Ashgill sequence in the Welsh Basin show that they have different provenance. Gondwana-derived continental crustal m aterial dominates the Nd-Sr isotope signatures of the fine-grained roc ks whereas the pebbles sample the Avalonian basement. Detritus from Go ndwana and Avalonia accounts for the isotopic composition of most of t he lower Palaeozoic sedimentary rocks of Southern Britain and this sug gests that any contribution from the reworking of Lower Palaeozoic vol canic rock is minimal.