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Geochemistry and stratigraphic relations of middle Proterozoic rocks of the New Jersey Highlands

Richard A. Volkert·Avery Drake
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Abstract

Middle Proterozoic rocks of the New Jersey Highlands consist of a basement of dacitic, tonalitic, trondhjemitic, and charnockitic rocks that constitute the Losee metamorphic suite. These rocks are unconformably overlain by a layered supracrustal sequence of quartzo-feldspathic and calcareous rocks. Abundant sheets of hornblende- and biotite-bearing rocks of the Byram intrusive suite and clinopyroxene-bearing rocks of the Lake Hopatcong intrusive suite were synkinematically emplaced at about 1,090 Ma. These intrusive suites constitute the Vernon Supersuite. The postorogenic Mount Eve Granite has been dated at 1,020?4 Ma and is confined to the extreme northern Highlands.

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Richard A. Volkert, Avery Drake. 1999. Geochemistry and stratigraphic relations of middle Proterozoic rocks of the New Jersey Highlands. https://doi.org/10.3133/pp1565c

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