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<br />• This portion of the formation, if encountered, was mostly in the bottom of <br />the "Hole" (Area H on Fig. 1). Projections based upon drill cores showed that most <br />of it could be removed before the "Hole" became too deep and narrow to mine. <br />Saguache Sandstone (Cs) <br />This formation is of Cambrian age and is quite common in western Colorado <br />near Glenwood Springs and on the north side of the San Juan Mountains near <br />Ouray. This formation is about 55 feet thick at this quarry, but elsewhere in <br />Colorado it can exceed 100 feet in thickness. It is a highly variable sandstone. The <br />Saguache is a fine-grained, deep red sandstone in the top 20 to 25 feet or so. This <br />blends into a red-green-white, coarse-grained sandstone which then blends into a <br />fine-grained, buff colored sandstone. The bottom 15 to 20 feet, or sometimes more, <br />is a friable white sandstone composed of well-rounded grains. These grains were <br />rounded by wave action as this portion of the sandstone was formed on a beach <br />that existed in this area at the beginning of the Cambrian. <br />• <br />This formation establishes the fundamental mining depth limit in Area H*. <br />That is, when this formation was encountered, mining was stopped. This formation <br />is exposed southwest of the south peak (Fig. 3) where it has a steep dip that in <br />some places can reach 70 or 80 degrees. It is also exposed near the bottom of the <br />valley just north of the active portion of the quarry (north of the north peak) and <br />within the upper portion of the pit below the middle peak just west of the landslide <br />scarp. The sandstone also occurs underneath the southwest portion of the "Hole". <br />The formation is folded and exhibits a gradual leveling of the dip to the east. <br />Pikes Peak Granite (Ypp) <br />West of the west fault and underlying the Saguache Sandstone is the Pikes <br />Peak Granite. The boundary between the Saguache Sandstone and the granite is <br />very sharp and is often no more than a few millimeters thick. Yet that sharp <br />boundary represents a vast unconformity that spans about 500 million years. Either <br />0 all rock deposited during that time was eroded away or it was never deposited. <br />TRANSIT MIX AGGREGATES 10 <br />PIKEVIEW QUARRY SLOPE <br />CTLIT PROJECT NO. CS17341-125 <br />S:ICS17000-174991CS17341.0 0 011 2 512. ReportslCS17341-125-R1-Final.doc