Gold in mineralized structures.
Available for Joint Venture
The La Rosita M.D. is in the south-western corner of the Deseado Massif, approximately 110 kilometres by good gravel roads and farm tracks to the north-east of Gobernador Gregores. La Rosita is less than 15km NE of Mina Martha and 21km North of Manantial Espejo Mine.
Magna Terra Minerals Inc.
Magna Terra Minerals has 100% control, through a leasing agreement with a private individual, of the La Rosita M.D. which constitutes 2900 Hectares on which the project is based. The neighbouring Mina Martha has been recently re-opened for exploration and production by Cerro Cazador S.A., a subsidiary of Hunt Mining Corp. In the case of success on La Rosita this would make Mina Martha a candidate for a JV or offtake partner. Prior to 2008 no drilling had taken place on the property. Geological mapping and further sampling was carried out during 2009 by a previous operator, and this was accompanied by a geophysical, IP and ground magnetic campaign. In September of 2010, 11 diamond holes were drilled, the most interesting being DDHLR04 which included an intercept of 3 meters with 0.761 ppm Au and 926 ppm Cu at a depth of 83 metres.
Geology: La Rosita is atypical in the Deseado Massif in that surface mineralization occurs in a complex area of shear zones which are generally hosted in carbonate sediments and sinters as well as felsic to intermediate volcanics.
The geology of La Rosita comprises a small basin measuring around 4 by 4 km which is formed in andesitic and dacitic volcanics and is occupied by highly deformed cherts, limestones and siltstones which are locally altered and mineralized. The formation of this basin is the result of extension and wrenching related to major regional and district scale structures which strike NNE, N-S, NNW, NW and WNW. The formation of the basin provided a site of high potential for geothermal and hydrothermal fluid flow as well as the topography for sedimentation which would ultimately cover the favourable stratigraphy and much of the evidence of hydrothermal activity. The presence of mineralization in sinters accompanied by associated soft sediment deformation, implies an environment in which sedimentation was accompanied by geothermal activity in the Jurassic and that later hydrothermal fluids, associated with structures in the underlying volcanics, had to pass through this column of unfavourable stratigraphy before brecciating and mineralizing sinters at the surface.
Magna Terra is currently using the geophysical and geological database to re-evaluate the property in terms of known regional structure and stratigraphy. We believe that drilling to date was well located in terms of zones of potentially high fluid flow but we deduce that the holes were collared and ended in stratigraphy which is unfavourable to vein formation. We are currently planning an IP program to determine the depth and position of favourable stratigraphy and structures for vein targets in underlying crystal tuffs in dilatation zones.