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gneisses are mapped as a series of folds, which are oriented roughly east-west and <br />have been broken and displaced by faults believed to range in age from Precambrian to <br />Tertiary. The two regional fault orientations that have been mapped within the property <br />are approximately east-west and north-south (Figure 3). <br />A notable geologic feature near the site is the Golden fault, which runs approximately <br />north-south and forms the eastern margin of the north-northwest trending hogback <br />immediately east of the quarry property. A mapped reverse fault trending roughly north- <br />south is located within the quarry property and constitutes the boundary between the <br />metamorphosed Precambrian bedrock (to the west) and the Pennsylvanian sedimentary <br />rocks (to the east) (Smith, 1964; Scott, 1972). The quarry property straddles this <br />boundary, with the majority of the processing plant and the entire asphalt plant located <br />east of the fault (Figure 3). The bedrock material east of the fault is dominantly <br />composed of upturned sandstones and shales of the Fountain Formation (Scott, 1972). <br />West of this fault, the material is typically mapped as migmatitic, quartzo-felspathic <br />gneiss with intrusions of granitic pegmatite veins (Scott, 1972). <br />Within the main pit of the quarry are three approximately east-west trending faults that <br />have been exposed as the quarry progresses, two of which are shown on the map. The <br />' fault located in Jackson Gulch has been informally named the Jackson Gulch fault is not <br />shown on the map due to the difficulty to map the surficial trace. The area has been <br />' extensively modified and fresh exposures have been covered up by backfill material <br />before measurements could be made. The unnamed fault that is exposed in the east <br />' and west walls of the main pit and ranges between 20 to 50 feet wide. Exposures of <br />this fault were visible in the northwest corner of the main pit during this field <br />investigation, with an average dip of 76° measured (Photo 3). This fault was also <br />mapped by Gable, as striking 260-270° and dipping 80-85° to the south, and will <br />' continue to be exposed as the pit deepens (Figure 3). <br />In the expansion area, Gable (1968) mapped the third fault that also trends roughly <br />east-west (Figure 3) and may form a structural block that results in distinguishable <br />