The Oscara prospect is located in the Puna region of Salta province in northwestern Argentina. Access from the city of Salta is through National route N 51 then the provincial road N 27 up to Tolar Grande town. The Oscara prospect is located 40km north from this town.
The Oscara prospect comprises 6 mining properties owned 100% by Regulus, covering in total near 19,155 Hectares. Manifestations of Cu-(Au)-Fe mineralization are found widespread over the entire property. These manifestations are hosted in rocks from Early to Late Paleozoic and also in poorly consolidated tertiary sediments and probably correspond to multiple superimposed stages of completely different styles of mineralization.
The geology of the Oscara project area consists of a strongly folded and faulted Early Ordovician aged volcano-sedimentary sequence, locally hornfelsed due to the emplacement of the “Chachas Formation” Late Ordovician to Silurian Magmatic complex. This complex is characterized by equigranular to porphyritic granites, granodiorites and monzonites forming medium size stocks and dikes which are locally related to quartz stockwork with low Cu-Au anomalies and associated to k feldspar-biotite and sericite-chlorite-epidote alteration. On the northern part of the property these rocks are overlain by a marine-continental sequence of Late Paleozoic age. Valley areas are filled by poorly consolidated sandstones and conglomerates of Eocene to Pliocene age, slightly tilted and locally faulted.
Different styles of copper and gold mineralization were described, all of them widespread along the property and strongly controlled by structures which were probably reactivated in different stages since early Paleozoic time. These can be grouped into:
According to Mansfield geologist’s old exploration reports, the Oscara prospect displays some affinities with Fe-Oxide Au-Cu Systems, comparing it with “La Candelaria” Cu-Au deposit in Chile.
1999-2007: Since 1999, several prospecting and explorative campaigns have been carried out over the Oscara area, mostly by Mansfield Minerals and later by Minera El Toro. During this period, a regional geological map was made by Mansfield geologists and also some detailed mapping over specific areas. A total of 1,010 rock and float samples were taken over the entire area, highlighting a “horseshoe-shaped” geochemical anomaly around the Cerro Oscara hill. These anomalies are predominantly of Cu and Fe with minor Au, Ag, Mo and Bi.
2008: The El Camino property was transferred to Pachamama Resources Inc. as part of a restructuring of Mansfield Minerals Inc.
2012: The property was transferred to Regulus Resources Inc. as part of the merger with Pachamama Resources Inc.