ISSN:
1432-1866
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
Notes:
Abstract Ophiolitic metabasite host rocks of the Whalesback cupriferous iron sulfide deposit, Notre Dame Bay, Newfoundland, have undergone extensive redistribution of alkalis and lime. Such alteration (hydrothermal alteration, halmyrolysis) occurred before Acadian deformation and chlorite-zone greenschist facies metamorphism. The pyritic ores occur in chloritized rocks within such altered metabasites. Areas of intense chloritization, usually associated with silicification and minor sericitization, represent a more advanced stage of alteration. The most striking bulk chemical change in the ore zone is the almost complete leaching of sodium and calcium from the host metabasites. Increases in iron and sulfur contents and erratic enrichment in potassium are also characteristic. No significant changes are shown by SiO2, Al2O3, TiO2, MgO and MnO. Though subsequently metamorphosed to the chlorite zone of the greenschist facies, wall-rock alteration appears to have originally been chemically similar to that observed in the Cypriot cupriferous iron sulfide ores except for high μCO2 associated with hydrothermal activity in the Whalesback area.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00204504
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