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Page 6 of 18 <br />Vegetation is typical of the Front Range, varying locally between heavy forest and <br />mountain meadows. The north facing slopes are densely wooded with Lodgepole Pine, <br />Engleman Spruce and Douglas fir. The low-lying areas are forested with Quaking Aspen, <br />Western Willow and Red Alder. South facing slopes are lightly wooded with Ponderosa <br />Pine, Lodgepole Pine, Rocky Mountain Juniper and Quaking Aspen (Turnburke, 2007). <br />The mine portals and auxiliary buildings are located on the south side of a moderately <br />steep valley formed by Coon Track Creek. This drainage separates Caribou Hill to the <br />west and Boulder County Hill to the east. Local relief as measured from the hilltops to <br />the valley floor is approximately 1500 feet. <br />3GEOLOGY <br />3.1 Regional Setting <br />This portion of Colorado is underlain by basement rocks comprising the North American <br />Craton, which has been intruded by Late Cretaceous igneous units. Deeply rooted <br />structural zones within the Precambrian rocks are linked to the development of the much <br />younger Colorado Mineral Belt. This belt consists of a northeast-southwest regional <br />trend of mineralization and ore deposits that is approximately 250 miles long and 80 <br />miles wide. <br />The Caribou, or Grand Island, mining district is located near the northeastern exposed <br />limit of the Colorado Mineral Belt. At a smaller scale, the area is part of the Front Range <br />mineral belt on the northern margin of the Idaho Springs-Ralston shear zone of the <br />Colorado lineament. This Precambrian fracture zone localized alkaline and calc-alkaline <br />igneous activity and associated mineral deposits during the Laramide orogeny. Deposits <br />in the district have been described by the U.S. Geological Survey as “polymetallic veins <br />with abundant carbonates or that occur in wallrock altered to contain carbonates.” <br />Confidential mapping of numerous veins, faults and fractures on the Cross Mine property <br />is available for inspection by DRMS at the mine site. <br />3.2 Geologic Units <br />The Cross-Caribou Consolidated claims area is underlain by the Precambrian age Idaho <br />Springs Gneiss, Boulder Creek Granodiorite, and Swandyke Hornblende Gneiss, and <br />the Tertiary age Caribou Monzonite. Precious metal veins are located hosted exclusively <br />within the Idaho Springs Gneiss and the Caribou Monzonite. Descriptions of the geologic <br />units and formations presented here are adapted from Moore et al., 1957 and Holland <br />1994.