ISSN:
1432-1866
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
Notes:
Abstract Sulphide separates from mineralisation in Archaean and Palaeoproterozoic host rocks of the Disko Bugt area, central West Greenland, have been analysed for trace elements and Pb isotopes. Isotopic compositions of lead from sulphide separates of Archaean supracrustal rocks show wide variations. Archaean semi-massive sulphides and sulphides separated from felsic metavolcanites yield an errorchron age of 2821 +77/−82, with a model μ1 value of 7.36; this is comparable to the estimated age of the supracrustal rocks. The two most prominent mineralised sites, the Andersen and Eqip prospects, have their own unique Pb isotope pattern; the Andersen prospect is considered to represent the result of an upper crust of Palaeoproterozoic process. The sulphide separates of Palaeoproterozoic epigenetic mineralisation hosted in shear and fault zones in the supracrustal rocks has a common origin, e.g. linked to a metamorphic peak and/or hydrothermal alteration. Gold-bearing samples indicate a local origin for associated sulphides; no regional processes seem to be involved in the formation of the gold occurrences.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s001260050145
