Mafic-dominated volcanogenic sulphide deposits in the Troodos ophiolite, Cyprus Part 1 – The deposits of the Solea graben

Abstract

The Solea graben in the Troodos ophiolite of Cyprus is host to some of the largest and richest cupriferous sulphide deposits on the island. The graben is oriented in a northwesterly direction and defined by similarly oriented dykes and faults. The deposits within the graben display a variety of characteristics which reflect their mode of genesis. They include deposits displaying classic exhalative genesis, as well as others which formed at some depth below the seafloor, or by fluids which travelled away from their source to deposit sulphide on the surface of the ocean floor. A special case is the Phoenix deposit which is the result of supergene enrichment from the weathering of massive sulphide. A strong control of ore deposition is evident for some of the deposits by a major structure interpreted as an oceanic detachment fault. Other deposits are localised at the intersection between axial structures and transfer faults. However, in all cases, an underlying heat source appears to have played a major role in ore deposition. The location of the deposits at the top of the volcanic sequence is consistent with an off-axis setting.

The geology of the northern part of the apliki Cyprus-type ore deposit

“…The samples were pulverized and homogenized at the University of Athens, Department of Geology and Geoenvironment and analyzed by ALS, Ireland and AcmeLabs, Canada by ICP-MS (SiO2, Al2O3, CaO, Cr2O3,Fe2O3, K2O, MgO, MnO, Na2O, P2O5, TiO2) and ICP-AES, (Ag, As, Cd, Co, Cu, Hg, Fe, Ni, Pb, S, Se, Sb, Zr, Zn) except for gold which was analyzed by AAS using a Perkin-Elmer 1100B device at the University of Athens. (Adamides, 2010a). Εικ.…”

“…The Apliki deposit is located in the western part of the Solea graben (Varga and Moores, 1985) which can be construed as a special tectonic feature, of north-northwest orientation, hosting some of the largest massive sulphide deposits in Cyprus (Adamides, 2010a). The Mavrovouni and Apliki deposits are in the western edge, while the Skouriotissa group deposits in the eastern edge of the graben.…”

“…Adamides (2010a) suggests that the Mavrovouni and Apliki deposits are localized by structures which are possible oceanic detachment faults. These sulphide deposits have been exploited both in ancient and modern times.…”

“…Initial exploration at Apliki started in 1935 and the presence of sulphide mineralization was documented in 1937 (Bruce, 1947 (Adamides, 1982). On the north side of the opencut a small amount of low-grade disseminated ore still remains, while the southern extensions merge into altered ground and are mainly covered under waste dumps (Adamides, 2010a). It should be noted that there is an absence of scientific studies pertaining to the Apliki deposit with the notable exception of the unpublished studies of Hellenic Copper Ltd. and CMC which have been reviewed and reworked by Adamides (2003a;2010a).…”

“…On the north side of the opencut a small amount of low-grade disseminated ore still remains, while the southern extensions merge into altered ground and are mainly covered under waste dumps (Adamides, 2010a). It should be noted that there is an absence of scientific studies pertaining to the Apliki deposit with the notable exception of the unpublished studies of Hellenic Copper Ltd. and CMC which have been reviewed and reworked by Adamides (2003a;2010a). The aim of this paper is to study the geology of the northern part of the opencut of the Apliki mine including the chemistry of the ore and the hydrothermal alteration of basaltic Pillow Lavas.…”