Iron Creek Capital Corp. (TSX-V: IRN) has announced progress on its 27,000 hectare Pampa Buenos Aires Project in northern Chile, which is being explored in joint venture with Andina Minerals Inc. (TSX-V: ADM).
The project covers nearly 18km of continuous strike length of the prospective Dominador Fault Zone (DFZ) in the Palaeocene-Eocene volcanic belt which hosts some of the most important precious metals and copper deposits in Chile.
Highlights of the recent work at PBA, which focused on surface colluvial sampling, include:
- Definition of several trends with broadly coincident arsenic and antimony anomalies - the typical geochemical pathfinders to El Peñon style low-sulphidation epithermal precious metals veins - in mostly post-mineral covered areas.
- A large area of molybdenum and zinc anomalies in post-mineral cover, centred around outcrops with advanced argillic alteration that may represent the highest levels of a porphyry copper system.
Iron Creek and Andina plan to follow up these anomalies with geophysics to better define the specific mineralized structures and veins in bedrock, ahead of drill testing. CSAMT will most likely be used as it has worked well at Yamana's El Peñon and Fortuna deposits, successfully detecting narrow quartz veins and similar structures.
Iron Creek and Andina are exploring PBA for El Peñon / Fortuna and Guanaco-style epithermal gold and silver mineralization and also for possible porphyry copper mineralization under a 50:50 joint venture. The project is located approximately 110km northeast of the coastal town of Taltal, 15km southwest of Yamana's Peñon and Fortuna deposits (+6 million oz gold and +185 million oz silver), and immediately north of Iron Creek's Pampa Sur project.
Geological Setting of Pampa Buenos Aires
The Palaeocene to Early Eocene Volcanic Belt of northern Chile extends north-south for about 600km and is bounded to the west by the Coastal Cordillera and to the east by the Domeyko Cordillera. The geology of the belt is dominated by Late Cretaceous to Early Tertiary calc-alkaline to sub-alkaline bimodal volcanic rocks that range from basaltic andesite to rhyolite, and by sub-volcanic porphyritic intrusions and granitoid stocks.
The portion of the belt between Sierra Gorda in the north and Sierra Overa in the south, which includes PBA, is characterized by exposures of felsic volcanic rocks and, significantly, is host to several precious metal epithermal deposits including the El Peñon and Fortuna gold-silver deposits, as well as other significant precious metal deposits at San Cristobal, Faride, El Soldado, Cachinal de la Sierra, El Guanaco, Amancaya and Sierra Overa.
The geology within PBA is broadly similar to that seen at El Peñon/Fortuna, consisting of Late Cretaceous, Palaeocene and Eocene andesitic to rhyolitic flows, domes, tuffs and minor intrusive rocks, although much of the PBA property is obscured by post-mineral gravels.
The main outcrops are located at Cerro Buenos Aires to the southwest, where a partially silicified rhyolitic dome complex is exposed, and Cerro Blanco to the northeast, where advanced-argillic altered volcanics are exposed. The property is cut by strands of the DFZ, which defines the structural grain of the project area.
The 2010 work program built on earlier work carried out from late 2006 to end 2008. Reconnaissance geochemical pH and colluvial/soil sampling surveys were completed on 1km spaced lines over the entire post-mineral covered portion of PBA, with 1,250 samples collected.
A more detailed survey is currently underway, combining geochemical pH and colluvial/soil sampling with rock-chip sampling and detailed geological mapping over the Cerro Buenos Aires hill. This work is scheduled for completion during November 2010.
Recent Results to Date
The recent colluvial and soil geochemical programs at PBA highlighted partially coincident arsenic and antimony geochemical trends, supported locally by mercury anomalies. Arsenic, antimony and mercury are three of the key pathfinder elements for El Peñon/Fortuna style, low sulphidation epithermal precious metals veins. None of the priority arsenic/antimony/mercury geochemical anomalies defined here coincide with previous drilling carried out on the property.
A particularly strong coincident arsenic and antimony anomaly occurs on the southern flanks of the Cerro Buenos Aires hill. Some 6km further to the north, a strong north to north-northeast trending arsenic anomaly with minor antimony occurs in an area largely covered by post-mineral gravels.
Several broadly coincident arsenic and antimony geochemical anomalies occur to the east of the DFZ, also in areas mostly obscured by post-mineral gravels. Some of these anomalous trends are supported by sporadic mercury, zinc, copper and silver anomalies.
An important arsenic and antimony geochemical anomaly in the south-central part of the property, immediately to the east of the DFZ, is open to the south-southeast and is contiguous with a significant anomalous trend on Iron Creek's Pampa Sur property (see IRN press release dated September 30, 2010).
Also of interest from the geochemical data is a large area of molybdenum and zinc anomalism in the gravels in the north-eastern quadrant of the property, centred on the Cerro Blanco area. Nearby outcrops display advanced argillic hydrothermal alteration styles typical of the higher erosional levels of a porphyry copper system. Molybdenum is commonly associated with porphyry copper deposits, and zinc anomalism is common on their peripheries.
Other smaller anomalies of one or more of these key indicator metals occur within the property, and may prove to be significant.
Geochemical samples are collected in accordance with accepted industry standards and best practices. Iron Creek carries out its own in-house pH measurements on colluvial and soil samples and applies standard protocols as part of the quality control methodology. Samples are then submitted to ALS Chemex Laboratories in La Serena, Chile, for preparation by PREP41 (250gr), with digestion by aqua regia and analysis for 51 elements by ICPMS. Gold is analysed by 50gm fire assay. As standard procedure, Iron Creek conducts routine quality-assurance and quality-control analysis on all assay results, including the systematic utilization of certified reference materials, blanks and field duplicates.
Demetrius Pohl, P.Geo. is the Company's Qualified Person as defined by National Instrument 43-101, and is responsible for the accuracy of the technical information in this news release. Dr. Pohl has verified that it is an accurate summary of the results from the Pampa Buenos Aires exploration programme to date.
Source: Iron Creek Capital Corp.