Status: Available for Option
The target at El Toro is a mineralized brecciated vein system containing gold and silver in a 2.5 km long area controlled by the NE trending Los Cochis fault. This fault is part of a larger flat lying shear zone believed to be related to thrust faulting. The targeted vein system is 6 km in length and varies in width from 2 to 35 meters. Metamorphosed sediments in contact with the Los Cochis fault form skarns in mineralized structures containing quartz veins and small replacement bodies with Pb, Cu, Zn and occasionally Au and Ag.
Location and Setting
The El Toro claim lies approximately 84 kilometers northeast of Hermosillo, Sonora Mexico.
The property consists of one mining claim covering 207 Ha. An internal claim is 37.6 Ha and home to small historic mine workings.
The area was previously explored by Cardero Resources in 2008 but no information is available.
The oldest rocks, roof pendants containing Paleozoic quartzite and limestone, are found above Cretaceous granite, granodiorite and monzonite. The units are unconformably overlain by Tertiary to Cretaceous rhyodacite tuffs and Eocene andesites and rhyolites. Thrust faulting followed by basin and range tectonics has displaced the Paleozoic and Cretaceous rocks and also formed structural pathways for hydrothermal fluid migration.
Structure and Alteration
Shear hosted vein structures are the main target of mineralization at El Toro. These structures are characterized by intense alteration and form iron stained silicified bodies. Along the N70E trending Los Cochis fault, silicified crests pinch and swell to form outcrops between 2 and 35 meter wide. Samples taken from silicified outcrops have returned gold values up to 0.72 ppm Au.
A mineralized area extends approximately 2.5 km along strike. Mineralization is mainly associated with the Los Cochis fault where vein breccia is observed as quartz vein filling of cracks. Some mineralized outcrops are shaped as small oval mounds. Skarns produced at the intrusive contact with calcareous sedimentary rocks contain base metals (Pb, Cu, and Zn) and are occasionally accompanied by gold and silver.
Conclusions and Recommendations
Outcrops in the Los Cochis fault system are characterized by vein breccia and contain alteration minerals and textures that suggest the area could contain silver and gold mineralization. Mineralized structures extend at least 2.5 km and vary in thickness from 2 m to 35 m. Recommendations include sampling and detailed mapping of the Los Cochis fault and any parallel structures.
“THE TECHNICAL INFORMATION WITHIN THIS DOCUMENT HAS BEEN REVIEWED AND APPROVED BY GREGORY A. BEISCHER, PRESIDENT & CEO OF MILLROCK RESOURCES INC. MR. BEISCHER IS A QUALIFIED PERSON AS DEFINED IN NI 43-101.”