The Spring Peak project is a well preserved, low-sulfidation epithermal gold system containing widespread anomalous to high-grade gold in surface rock chips, and up to 1.93 g Au/t in historic, shallow drilling. Arsenic, antimony and mercury are also anomalous in rocks and soils, in an area of strong hydrothermal alteration occurring along a predominant west-northwest structural trend, with subsidiary north-northeast and east-northeast trends. The coincidence of anomalous geochemical trends and structural measurements on faults, fractures and veins underpin several high-grade bonanza vein targets, none of which have ever been drilled.
Multiple colloform banded veins ranging up to approximately 3 feet (1 meter) in width at surface are present, with grades as high as 35 g Au/t. Banded veins are hosted in Cretaceous granite and Jurassic metasediments with gold values occurring along west-northwest, east-northeast, and north-northeast striking structural zones up to 1.5 miles (2.4 km) long. The system is well preserved as evidenced by paleosurface features including a sinter terrace, geyserite, and a hydrothermal eruption breccia apron. Numerous bonanza vein targets are present, and these have not been drill tested, as prior operators from the early 1980s to early 1990s drilled mostly shallow, vertical holes, apparently exploring for bulk tonnage mineralization.
Location and Claims
The Spring Peak project comprises 37 unpatented lode claims in the Bodie Hills about two miles (3 km) southeast of the Aurora District in Mineral County, Nevada. Kinetic Gold controls a 100% interest in the claims, subject to an underlying lease agreement and royalty.
The project is in the west-central part of the Walker Lane, along a northeast trend of epithermal gold deposits including Bodie, Aurora and Borealis. Historic production from these deposits was nearly 4 million ounces of gold and 28 million ounces of silver, and current (M, I & I) resources of 2,313,600 ounces of gold are reported at Borealis (Gryphon Gold website).
At Spring Peak, an erosional window through Miocene and Pliocene volcanic units exposes Cretaceous porphyritic granite and Jurassic metasedimentary country rocks in the south-central Bodie Hills. At least eleven major eruptive centers were active in this area between 15 Ma and 5.5 Ma, and seven major, and many smaller hydrothermal systems are associated with this volcanism. The largest known precious metals systems were formed at Bodie, Aurora, and Borealis during this period. In the Spring Peak area, Miocene and Pliocene andesite and dacite are the dominant volcanic units. In the northeast and eastern part of the property, Pliocene basalt flows and a rhyolite flow dome complex overlies the other volcanic units and are the youngest volcanic units in the area.
West-northwest and east-northeast fault zones are the dominant structures on the property. These intersect one another near the center of the property where north-northeast faults are also present. All three of these fault sets, and their intersections, are associated with alteration, banded veins, and mineralization. Some structures are occupied by rhyolitic to dacitic dikes that strike north to north-northeasterly and roughly east-west. West-northwest and east-northeast faults are associated with andesite dikes, hydrothermal eruption breccias and sinter.
Much of the exposed alteration is silicification. Limonite derived from disseminated sulfides usually accompanies silicification, which may grade upward into opalization which is usually quite intense, converting much of the rock to opal or chalcedony. In the north central part of the property the opalization becomes less dense and acid leached up section. Argillized rocks are poorly exposed at surface but are commonly reported in historic drilling.
Vein float is common in several west-northwest, east-northeast, and northeast zones but few veins are exposed in outcrop. The veins are colloform banded chalcedony and very fine-grained sugary quartz, with observed widths at surface up to 3 feet (1 meter). Some bands have a greenish stain, probably from included clay. Bladed quartz after calcite texture, indicative of boiling is common. Goethite locally occurs in the veins and some iron sulfide, stibnite and stibiconite are present at surface.
An induced polarization and resistivity survey was completed on the property by previous workers and consisted of 250 foot dipole spacing along eleven parallel, northeast lines, spaced approximately 500 feet apart. Each IP line is approximately 4500 feet long. A strong untested west-northwest trending chargeability response occurs under cover at the center of the property and is parallel to, but north of, the main west-northwest zone of exposed mineralization. A resistivity anomaly is also present and partially coincides with the chargeability anomaly. These features may represent a zone of increased sulfide, and potentially increased gold values at moderate depth.
Rock chip values range up to 35.7 g Au/t in vein material and widespread gold values of 0.2 to 3.5 g Au/t have been sampled. Silver values are generally low, but range up to 95.6 ppm in localized veinlets. Arsenic ranges up to 1200 ppm in vein material, and antimony as high as 2760 ppm has been sampled from stibnite-bearing vein material. Mercury reaches levels up to 2880 ppm and is generally highest in a small area of opaline leached rock in the north central part of the property, probably as a result of condensation from steam heating in this area. Base metals are generally low but some veinlets in silicified granite carry up to 150 ppm molybdenum.
Maps and Figures
SP Geology Legendclick on image to enlarge
SP Geologyclick on image to enlarge
Arsenic in Soils with Au in Rock Chipsclick on image to enlarge
SP Cross Section A-Aclick on image to enlarge
SP Cross Section B-Bclick on image to enlarge
SP Cross Section C-Cclick on image to enlarge