Both of these rock assemblages are present in drill core from the mineralized zone at Copper Lake (Black 1996; Kontak 2006).
Based on core logging and assessment reports (Lacombe 1962; Black 1996), it appears that a package of mainly fine-grained, greenish sedimentary rocks is located on the north side of the area, whereas grey to black sedimentary rock units dominate in the south; locally the boundary between the two rock types is a zone of brittle deformation. 1995), but these rocks were not observed in examination of the drill core from Copper Lake.
In order to determine the age of mineralization and provide an important time constraint for developing a metallogenic model, direct dating of the mineralization and associated alteration was undertaken.
At Copper Lake, mineralization occurs in a set of sulphide-carbonate fissure veins hosted by fine-grained metasedimentary rocks of the Middle Devonian Guysborough Group. Nova Scotia Department of Natural Resources, Report ME 2005-1, pp.
As part of this study additional geochronological data were obtained for detrital zircon (U-Pb age of 1634 ± 11.2 Ma) from the host sedimentary rocks, as well as timing of thermal events at ca.
370–380 Ma, 350 Ma and Ar and chemical Th-Pb dating of host rocks and monazite.
1a) which separates the Avalon and Meguma terranes in this part of the Appalachian orogen. Much of this mineralization is related to widespread carbonate- and iron -oxide alteration (i.e., specular hematite with magnetite absent) regardless of the age or nature of the host rock.
1), the area is underlain by rocks of the Middle Devonian Guysborough Group, as constrained by a U-Pb zircon age of 389 Ma reported by Cormier . The stratigraphy is dominated by green- to grey-green siltstone and shale and grey to black laminated siltstone, silty shale, and shale.
Heaman Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, T6G 2E3, Canada ABSTRACT The Copper Lake area of mainland Nova Scotia is one of several vein-controlled mineralized (Cu-Au-Co) systems associated with widespread carbonate and iron-oxide alteration proximal to the east-trending Cobequid-Chedabucto Fault System. of Lower Cretaceous sandstones onshore and offshore Nova Scotia from electron microprobe geochronology and chemical variation of detrital monazite.
Although this mineralization has been known for decades, its metallogenic affinity remains poorly defined, and in recent years an IOCG (iron oxide-copper-gold) model has been suggested.
This site has been studied in more detail than others (Kontak 2006) and, therefore, formed the basis for a comprehensive, multi-method (Re-Os, Ar, U-Pb, Th-Pb chemical dating) geochronologic study. white mica ages reveal Neoproterozoic/Paleozoic provenance and an Alleghanian overprint in coeval Upper Ordovician–Devonian rocks of Meguma and Avalonia.
In this paper, the results of this work are presented and discussed in the context of the possible origin of this IOCG-style mineralization.