SummaryNewmont and Placer Dome (per Bravo Ventures Inc news releases) have made large land acquisitions in Kobeh Valley through aggressive staking. For the most part these acquisitions are driven by a general conceptual exploration model that proposes that Kobeh Valley is permissible for the occurrence of a another large pediment-covered mega gold systems similar to those that were discovered in Crescent Valley (Pipeline-Cortez-Cortez Hills) and appear to project further east southeast into Horse Creek Valley (ET Blue and Placer Dome and others targets).
Kobeh Valley is south of Crescent Valley but also in the within Battle Mountain-Eureka Trend. The area is framed by the Barrick Gold's Archimedes deposit to the south east and the Gold Bar deposit to the northwest. Other smaller gold deposits occur on the north range fronts fringing Kobeh Valley.
The Cortez Joint Venture's discoveries, exploration targets and land acquisitions cumulatively have resolved the Cortez Trend as a discrete WNW belt of deposits extending from Horse Creek Valley on the south to through the Shoshone Range on the north. A similar belt could be proposed for the area between Gold Bar and the Archimedes Mine and should be explored in similar fashion. Doubtless this is why Placer Dome (previously) and Newmont currently are conducting aggressive exploration in the area.
The Cortez Trend is comprised of a WNW trend of world class deposits, lower plate carbonate windows and axes of intrusive bodies. Blue hachured patterns are lower plate carbonate windows, pink patterns are intrusives with WNW axis. Pipeline, Cortez.
This map shows that the DAME-ETTU (in Red) project occurs along the same deep crustal gravity gradient as the most significant deposits of the southern Battle Mountain Eureka Trend. (The strontium 76 line is the red line superposed onto gravity)This gravel covered ground is very fertile for a blind discovery between Gold Bar and Archimedes
This setting presents an exploration analogue to Crescent Valley where small deposits in the surrounding range were direct indicators to the larger pediment covered gold systems discovered in recent years.
Crustal or basement scale (Cenozoic near surface affects filtered out) gravity provided by the US Geological Survey show that Dame and ETTU lie along the same gravity gradients as Pipeline, Cortez, Cortez Hills, and Tonkin Springs. This crustal break probably coincides with favorable transitional facies carbonate host rocks important to localize gold deposits.
Miranda, Newmont and Placer Dome have used filtered gravity data to indicate favorable structural fabric and relatively shallower parts of the Valley. In the case of the Placer Dome block they have also reacted to rock samples and assays gained from an oil well adjacent to Bravo Venture's South Lone project. Sampled splits from this well indicated the presence of anomalous lower plate Roberts Mountain formation and mineralized gravel at the basement contact suggesting erosion and transport of detritus from an inferred nearby deposit exposed at the paleo surface beneath cover.
Miranda Gold Corp has taken a significant position of 300 claims extending from Lone Mountain 6.5 miles southeast in the direction of the Archimedes Mine on interesting WNW and NNW basement ridges. Miranda feels that if the Bravo Venture mineralized gravels in an oil well represent a significant gold system, it would likely produce a northwest-southeast-trending, district-scale array of en echelon deposits associated with west-northwest, north-northwest and northeast-trending fault blocks. Miranda has located its claim block accordingly. (Black grid is PLS sections (1mile))
Land positions on this compilation map suggest that the ''Archimedes-Goldbar'' Trend is developing as analogy to Cortez Trend. (Placer Dome and Miranda claims in Kobeh Valley approximate) Miranda proposes that discrete WNW deposit trends occur as subsets within the larger NW Battle Mountain Eureka Trend.
TargetNevada is a patchwork of adjoining basin and ranges. Most experienced Nevada geologists feel that the next wave high-value, company-building gold discoveries are likely to come from the extensive areas of the historic gold trends that are covered by gravel. This will require high-risk exploration plays that offer high reward in difficult but under explored areas. Exploration for covered gold deposits will require a time commitment to a larger area, and the application of efficient and effective targeting technologies that develop vectors to blind mineralization. Discovery will require both intensive systematic drilling and the placement of subtle geologic data gained into the right context for narrowing down large covered areas into those areas most likely to conceal world-class ore bodies.
ExplorationMiranda is seeking a joint venture partner for its DAME and ETTU properties in Kobeh Valley. Suggested exploration would include gas (mercury and O2/CO2) surveys, gravity and electrical geophysical surveys, possible emerging ''deep penetrating geochem'' surveys previous to drilling. Initial wider spaced grid drilling into basement to first look for geochemical dispersion patterns and subtle alteration might indicate the presence of a larger system footprint that could surround possible ore bodies.
Miranda thinks that large gold deposits exposed and oxidizing at the bedrock/gravel interface under valleys and pediments will have broader clastic gold dispersion patterns due to paleo erosion on the basement and notable distinguishable effects on surrounding ground water. These patterns may vector into ore-bodies.
Large buried gold deposits tend to be surrounded by much larger gold anomalies as clastic dispersion trains and also can significantly affect surrounding ground waters. Recognizing these broader footprints could be used to vector to ore-bodies.
Similar Geochemical Dispersion patterns and geophysical signatures tend to occur around world-class gold deposits. These features could be used on a district and project scale.
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