Publication Type:

Journal Article

Authors:

Piercey, S. J.

Source:

Current Research (Newfoundland and Labrador. Geological Survey), Government of Newfoundland and Labrador. Geological Survey, St. John's, NL, Canada, p.169-178 (2007)

ISBN:

1707-665X

Keywords:

Appalachians, Canada, classification, copper ores, Dunnage Zone, eastern canada, gold ores, lead ores, massive deposits, massive sulfide deposits, metal ores, mining geology, Newfoundland, Newfoundland and Labrador, North America, Northern Appalachians, ore grade, silver ores, VOLCANISM, zinc ores

Abstract:

The Newfoundland Appalachians host more than 40 volcanogenic massive sulphide (VMS) deposits, and each contain >100 000 tonnes of sulphide-rich material. Collectively, they represent an aggregate geological resource of about 112 million tonnes (geological resource) with production and reserves of approximately 46 million tonnes. The VMS deposits are predominantly hosted by Cambrian-Ordovician volcanic-arc, arc-rift, and back-arc basin assemblages within the Dunnage Zone. The deposits are classified into three main groups, i.e., mafic-type deposits (Cu-rich, mostly hosted by ophiolitic rocks), bimodal-mafic-type deposits (Cu-Zn rich, hosted by bimodal sequences dominated by mafic rocks) and bimodal-felsic-types (Zn-Pb-Cu-rich, hosted by bimodal sequences dominated by felsic volcanic rocks). Some bimodal mafic- and mafic-type VMS deposits are also enriched in precious metals, but many felsic-bimodal deposits also show significant Au and Ag enrichment. There is a very good database from previous research on these VMS deposits, and this has influenced wider models for the genesis of such deposits. However, many unresolved questions remain, especially in the light of research work conducted over the last two decades elsewhere in Canada and around the world. This short paper is intended to highlight these gaps in our knowledge, with the objective of stimulating further applied research on both regional and local scales.

Notes:

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