The property referred to herein as the Eagle Mountain claims consists of 248 placer claims, containing 31 blocks of 8 claims each. It measures approximately 8 km N-S by 4 km E-W, and covers 4,960 acres.
The claims are located 10km SSE of Death Valley Junction in Inyo County, California, within 15km of the Nevada border. They cover most of the Eagle Mountain Salina found within the Alkali Flats area. All are on BLM land within the Mojave Desert and are located some 200km SE of Albemarle’s Silver Peak Lithium Mine at Clayton Valley, Nevada, the only lithium producing mine in North America.
Figure 1: Looking South from the north end of the Eagle Mountain Salina. Eagle Mountain (centre right), 10 km south of the photographer, is localized along a WNW-trending cross fault which truncates the regionally extensive N-S basin.
The western and central parts of the salina were periodically held and explored for their contained borate minerals between 1880 and 1930.
The United States Geological Survey (USGS) reported sampling and drilling in closed basins throughout portions of Nevada, primarily in and around the Clayton Valley region, and adjacent California. USGS open File Report 80-1234, 1980 especially targets 23 playas in the Mojave Desert of southeast California including the Alkali Flats area, which contains the claims. Their work at Alkali Flats consisted of taking bore-hole samples from a 102.1m deep hole located near the western margin of the claims area. Of the 68 bore-hole samples taken, 45 returned lithium values between 300 and 999 ppm, and 22 samples between 100 and 299 ppm. In addition, three brine samples were collected from this hole returning 0.07, 0.12 and 0.12 ppm lithium and 1,500, 1,000 and 1,100 ppm chlorine at 41.4, 71.6 and 102.1 meters depth, respectfully. No borate or potassium results were disclosed. The bore-hole rock sample results were the strongest anomalous values obtained by this USGS study of the 23 playas. This is attributed to the drill hole being positioned outside of the priority basin, in an area were surficial water mixing diluted the results.
Of the major sources of lithium - brine, pegmatites and lithium clays - the brine deposits are dominant and are expected to maintain their dominance primarily due to the competitive cost of production; therefore our emphasis is on brine deposits.
Figure 2: Schematic Deposit Model for Lithium Brines (after Bradley et al, USGS open – file report 2013 – 1006)
The selection of the Eagle Mountain property was based on an assessment of the various known salars in the region primarily using the work by the USGC (D. Bradley, et al, 2013, A Preliminary Deposit Model for Lithium Brine and Munk et al, 2011, Final Technical Report: Lithium Brine Resources, A Predictive Exploration Model) as a conceptual model. This model is based on features believed to be favorable for localization of economic lithium deposits at Clayton Valley , which hosts the only North American producer (Albemarle’s Silver Peak Mine), and the large Chilean deposits from the Salar de Atacama in Chile. For reference their schematic presentation is included herein (Figure 2). Their observation (C. Bradley et al, 2013, page 1) is noted that “All producing lithium brine deposits share a number of first-order characteristics: (1) arid climate; (2) closed basin containing a playa or salar; (3) tectonically driven subsidence; (4) associated igneous or geothermal activity; (5) suitable lithium source-rocks; (6) one or more adequate aquifers; and (7) sufficient time to concentrate the brine”. All these characteristics except (6) clearly apply to the Eagle Mountain property.
A satellite image for the claims and surrounding area is presented below (Figure 3A, 3B) together with a synoptic interpretation of the structural setting. The salina lies within a north-south trending basin essentially closed to the south. This basin interacts at the western fringe with the Amargosa River Drainage which is recognized by the USGS as regionally enriched in lithium ( 18 springs and wells in the Amargosa Desert averaged 105 micrograms per liter lithium as compared to 2 micrograms per liter for the mean of 100 major municipal water supplies in the United States). The central and eastern positions of the basin are bounded by a major north-south range-front fault to the east. This trap basin is further defined by the west-northwest Eagle Mountain Fault to the west that separates the main trap basin from what is interpreted to be a zone of shallow mixing and erosion of the borates and evaporates on the saline’s western fringe. It is within this zone that the USGS, for ease of access, located their drill hole. The area which remains closed and a suitable trap for brines constitutes the vast majority of the property area.
Field relationships suggest that the salina was completely closed for an extended period of time, followed by a recent breach along the western fringe localizing the mixing zone, an area of dilution and scouring of the surface evaporates.
PROPOSED WORK PROGRAM
In order to systematically evaluate the potential of the property the initial work would entail geochemical sampling and geological mapping of the property. Samples would be collected on a 250 by 250 meter grid spacing over the playa in order to confirm lithium enrichment and to identify any zoning that may be present. An airborne gravity, Ztem and magnetic surveys would be contracted to provide information on the basin geometry and the location of potential conductive brine reservoirs.
Further work would be dependent on favorable results and is expected to entail ground seismic work and drilling.
Figure 3A Google Earth Image of the Eagle Mountain and Death Valley Junction Areas
Figure 3B Synoptic Interpretation (Preliminary) Showing the Location and Setting of The Eagle Mountain Claims. The Black Outline is the generalized location of the Claim Units.