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In the expansion area, Gable (1968) mapped a third fault that also trends roughly east- <br />west (Figure 3). This fault was initially exposed during the 2006 investigation, and was <br />noted by a distinct pegmatite vein that is surrounded by decomposed weak biotite rich <br />gneiss. The fault was exposed in a temporary wall along the western margin of the <br />expansion area, although accurate strike and dip measurements were not obtained due <br />to the high fracture density of the exposed material (Figure 3; Photo 4). <br />The granitic gneiss found in the quarry is generally hard and relatively competent. The <br />gneiss varies in color from grayish orange to dark gray, with occasional banding visible <br />along the foliation of the rock. The term foliation refers to the realignment of minerals <br />into a parallel orientation as a result of the intense heat and/or pressure of <br />metamorphism. The rock mass tends to be weakest along the foliation planes, which <br />ultimately results in a discontinuity set parallel to the orientation of the foliation. The <br />foliation orientation is the most prominent discontinuity set identified in the quarry and is <br />readily visible in the east and west walls. The rock foliations undulate in a synclinal and <br />anticlinal fashion, with noticeable variation in dip angles across each wall. <br />-4-