Volcanogenic cherts in the late Precambrian Conception Group, Avalon Peninsula, Newfoundland

Bedded rocks of cherty appearance are locally abundant and conspicuous in the late Precambrian Conception Group of the Avalon Peninsula, southeast Newfoundland. Structural, petrographical, and chemical data from a well exposed locality near St. John's indicate that these beds are tuffaceous, pr...

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Bibliographic Details
Published in:Canadian Journal of Earth Sciences
Main Author: Hughes, Charles J.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1976
Subjects:
Online Access:http://dx.doi.org/10.1139/e76-054
http://www.nrcresearchpress.com/doi/pdf/10.1139/e76-054
Description
Summary:Bedded rocks of cherty appearance are locally abundant and conspicuous in the late Precambrian Conception Group of the Avalon Peninsula, southeast Newfoundland. Structural, petrographical, and chemical data from a well exposed locality near St. John's indicate that these beds are tuffaceous, predominantly of acid vitric composition, formed by pyroclastic material derived from contemporaneously active subaerial volcanic sources accumulating in sea water, and subjected to submarine transport. Appreciable quantities of acid material were thus erupted in 'Conception time.'