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CRYSTAL PIT EXHIBIT B • SITE DESCRIPTION GEOGRAPHY AND GEOLOGY The geology of the site and surrounding area is interesting. The site is located on the north side of Pikes Peak and a short distance to the south of the Ute Pass valley. The Pikes Peak region is primarily composed of a batholithic intrusion of granite with an age of about 1.2 billion years. The Pikes Peak granite is one of the youngest granites in Colorado and exhibits unique characteristics. It is pink to reddish in color, primarily because of an abundance of feldspar. It is often very coarse grained. It is poorly fused and readily weathers into a gravel. Where the rock is harder it weathers into rather smooth surfaced, rounded mounds which sometimes exhibit extensive exfoliation. In some locations on Pikes Peak and in the • Rampart and Tarryall ranges to the north, the landscape presents a character somewhat reminiscent of Yosemite National Park in California. This landscape character does not occur on or near this site. Soils which develop from this granite tend to be highly erodable, have a low water holding capacity, are well drained, and yet can produce lush vegetation growth where conditions are appropriate. The soils and decomposed granite have been used extensively in the production of roadbase and other products. Unfortunately, once exposed, the decomposed granite tends to erode readily and is often difficult to revegetate without the use of topsoil. To the north of the site is the Ute Pass valley. This valley was formed in a weakness produced by a huge fault system which extends from the head of the valley eastward to Colorado Springs where it joins the Rampart Range Fault. Pikes Peak exhibits extensive and very large fault systems around its base. Some of these faults produced . displacements measured in miles. A few of the fault systems, .pa especially to the south of the peak, are complex systems where large .~ i