Tenke encouraged by early results at Alto Rico
2003-03-19 10:37 ET - News Release
Mr. Paul Conibear reports
ENCOURAGING EARLY RESULTS AT ALTO RICO GOLD PROJECT IN ARGENTINA
Tenke Mining has released encouraging early results from its exploration program under way at the Alto Rico gold project. The Alto Rico project comprises an extensive low sulphidation epithermal gold/silver vein and stockwork system located in the Patagonia region of Argentina.
Large corresponding geophysical and geochemical anomalous zones have been identified by the fieldwork currently under way. IP/resistivity surveys totaling 62 line kilometres have been completed to date profiling vein structures and stockwork zones defined as strong silicified swarms covered by colluvium. These zones are quite extensive and indicate further continuity of similar targets mapped in the surface program. In addition, 40 trenches encompassing over 2,500 metres have been opened, where the continuity and extent of the veins systems has been proved.
Continuing geochemical sampling returned results from 0.35 to 4.5 grams per tonne gold in veins and values up to 2.0 grams per tonne in stockwork together with mercury anomalies between 5,400 to 26,500 parts per billion Hg, arsenic between 180 to 951 parts per million As and antimony from 29 to 117 ppb Sb.
In addition, a large zone of resistors and chargeability anomalies covering an area of three km by one km has been identified on trend with the main vein and stockwork zone. This area is now being mapped.
The geology and structural features of the project area show banded textures with open-space fillings, bladed calcite replaced by quartz and other textures indicative of levels above possible boiling zones -- which are levels where the epithermal system reaches pressure and temperature conditions related with mixing of magmatic and meteoric waters that favour precious metals precipitation. The identification of such zones is key in determining the exposure and potential of these systems.
Generally, the target model at Alto Rico is high-grade gold/silver systems such as those found at Cerro Vanguardia as well as Meridian's Esquel gold deposits, located on similar volcanics within the Patagonia region of Argentina. The known extent of the Alto Rico vein system appears to be of large scale -- more than 12 kilometres of recognized vein length. There is a principal northeast trending quartz vein system, with five outcropping subparallel veins, which vary between one and 10 metres in width with an average outcrop width of three metres. These subparallel veins converge on a hill which shows signs of extensive stockwork, including strong silicification, acid leaching and argillic alteration. The mineralization is hosted in permeable dacitic to andesitic tuffaceous rocks.
Fieldwork is anticipated to be completed in early April. Data from the field program will be used to define drill targets and form the basis of a drill program expected to start by the end of April.
Along the same geological model, approximately 30 km to the northwest, the company holds another property known as El Macanudo. This property is also part of the overall Alto Rico project. El Macanudo comprises of a thick (up to 40 metres) and extensive (at least four-square-km) sinter sequence hosted in tuffs and ignimbrites of Jurassic age. Sinters are excellent indicators of low-temperature silica precipitation above active epithermal systems that have the potential to host precious metal deposits. This area has been targeted for mapping, geophysics and geochemistry. The area shows strong mercury, arsenic, manganese and calcium anomalies which are now being systematically sampled. Geophysics (IP/resistivity) indicates possible feeder structures below the sinter. |
