Comparative petrology and source of sediments in Newfoundland fiords

Comparative petrology of the gravel- and sand-sized fractions of sediments from Conception Bay, Placentia Bay, and Halls Bay, Newfoundland, has shown gravel clasts to be of the same composition as local bedrock, and sands to range in composition from litharenite to lithic arkose depending upon the p...

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Bibliographic Details
Published in:Canadian Journal of Earth Sciences
Main Authors: Slatt, Roger M., Gardiner, William W.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1976
Subjects:
Online Access:http://dx.doi.org/10.1139/e76-150
http://www.nrcresearchpress.com/doi/pdf/10.1139/e76-150
Description
Summary:Comparative petrology of the gravel- and sand-sized fractions of sediments from Conception Bay, Placentia Bay, and Halls Bay, Newfoundland, has shown gravel clasts to be of the same composition as local bedrock, and sands to range in composition from litharenite to lithic arkose depending upon the proportion of fine and coarse grained local bedrock. Sand-sized lithic fragments comprise the same lithologies as local bedrock. The petrology provides conclusive evidence that almost all of the sediments in each fiord are glacially eroded from local bedrock; they are deposited in the fiords and subsequently reworked. However, the occurrence and distribution of garnet and other less frequently occurring mineral and lithic species indicates that a minor proportion of the sediments has been transported into the fiords from offshore by ice-rafting and/or from the adjacent continental shelf by bottom currents.