Structural Controls on Porphyry Au-Cu and Au-Rich Polymetallic Carbonate-Hosted Replacement Deposits of the Kassandra Mining District, Northern Greece

摘要

The Kassandra mining district of northern Greece contains about 12 Moz Au in porphyry Au-Cu and Au-Ag-Pb-Zn-Cu carbonate replacement deposits that are associated with Oligocene-Miocene intrusions emplaced into polydeformed metamorphic basement rocks belonging to the Permo-Carboniferous to Late Jurassic Kerdilion unit and the Ordovician-Silurian Vertiskos unit. Regional extensional tectonics active since the middle Eocene resulted in the development of widespread normal and transtensional faults, including the Stratoni fault zone that hosts carbonate replacement sulfide orebodies. This structure has been previously interpreted as the tectonic boundary between the Kerdilion and Vertiskos units. Geologic relationships, structural patterns, immobile element geochemistry, and published zircon U-Pb ages suggest that the tectonic boundary between these lithotectonic units is an older structure and not a detachment fault as previously indicated.