Millrock Resources Inc. recently completed a seismic geophysical survey and drilling of a single reverse circulation borehole at its Monsoon copper project in southeast Arizona. The survey results and the drill hole indicate that it is unlikely that a large porphyry copper deposit exists within 500 m of surface. The project was the subject of an option agreement with FQM (Akubra) Inc, formerly Inmet Mining Corporation, a wholly owned subsidiary of First Quantum Minerals Ltd. (“FQML”) whereby FQML may have earned a 70% joint venture interest. FQML has advised Millrock that it will withdraw from the option agreement. Millrock believes there is potential for discovery of a porphyry copper deposit at greater depth and intends to seek a new funding partner to further test the targets developed.
Prior to the recent exploration phase Millrock had carried out property-wide biogeochemical sampling, soil sampling, water well sampling, and airborne ZTEM and magnetic surveys. The work was designed to search for buried porphyry copper deposits along the projected trend of the Safford copper deposits in Laramide-aged rocks that host copper mineralization in the district.
Reprocessing and interpretation of historic seismic data had led Millrock to believe that an upthrown structural block of Laramide-aged rock may be present, and that copper mineralization may exist in the shallow subsurface. A modern 2D seismic reflection survey was carried out to confirm the historic survey in an area where Millrock had discovered polymetallic anomalies in various geochemical surveys. Two lines totaling approximately 17 km were surveyed. Two possible interpretations could be made from the seismic data. One interpretation indicated the favourable Laramide contact was at an approximate depth of 500 m below surface. Another interpretation indicated a depth of approximately 1,000 m.
A vertically-oriented 500 m reverse circulation hole was drilled as a stratigraphic test and to determine the source of the geochemical anomaly. Results of the drilling suggest that an upthrown structural block does exist in the area tested. Tertiary volcanic rock was intersected at only 100 m below surface; a much shallower level than in holes drilled by prior explorers elsewhere on the property. However, the contact with the Laramide aged rocks must lie deeper than 500 m; most likely at an approximate depth of 1,000 m.
The technical information within this document has been reviewed and approved by Gregory A. Beischer, President & CEO of Millrock. Mr. Beischer is a Qualified Person as defined in NI 43-101.
Target: The target at the Monson property is a giant high-grade porphyry copper deposit (± gold and molybdenum). The project is located approximately 50 km (31 mi) south of the Morenci Mine and 50 km (31 mi) southeast of the Safford Mine, both giant porphyry copper deposits actively being mined by Freeport McMoran.
The property is covered by post-mineral Tertiary volcanic rocks or alluvium and remains largely untested for porphyry copper mineralization. Geochemical, geophysical and geologic data, however, suggests potential for the discovery of a buried porphyry copper deposit at Monsoon.
Location and Setting: The Monsoon property is located near Duncan in southeastern Arizona approximately 50 km (31 mi) southeast of Safford, Arizona. Topography varies from moderate to flat. Paved highway 70 passes just east of the property with good access to the property provided by dirt roads.
Geology and Mineralization: The Monsoon property is located southeast of the Safford Mine along the Safford porphyry copper trend as defined by known mineralization at the Safford (Dos Pobres, Lone Star, San Juan and Sanchez), Sol and San Jose porphyry copper properties. Geochemical and geophysical data further defines the Safford trend through the Monsoon property
The project area is covered by post-mineral Tertiary volcanic rocks and alluvium, however geochemical, geophysical and geologic data suggests potential for the presence of a buried porphyry copper deposit. Past drilling is limited to two shallow holes drilled in the 1990′s by Noranda. Neither hole penetrated Laramide-aged basement, drilling only post mineral alluvium. Zones containing anomalous copper and molybdenum values were intersected in both holes. The Laramide-aged geology of the property remains largely unknown and the porphyry copper potential unexplored.