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Ref. Page No.M2009-006 00062 <br /> GEOLOGY. [ref. 6.4.4, item (f).] Meadow Hollow Quarry sits near the top of the <br /> approximate 350-foot-thick "Lyons Formation" of stone. Lyons Formation stone <br /> produces is a high-quality flagstone and building stone. Lyons Formation stone is also <br /> used to produce aggregate or gravel composed of crushed and sieved Lyons sandstone. <br /> Most of the Lyons Formation was deposited in a wide-spread desert dune field about <br /> 290 million years ago (Early Permian Period), in which the prominent layers that produce <br /> the flagstone and flat-sided blocks are parallel to the "fossilized" dune faces. A dune <br /> typically has a gentle windward slope or face (sloping 50 to 150) leading up to a ridge or <br /> crest, then a steeper (301 to 351) down-wind slope (the slip face). These ancient dune <br /> faces form what is called "cross bedding," which is at various angles to the overall <br /> Layering of the Lyons Formation. The rock, in most cases, fractures or splits parallel to <br /> the cross bedding, producing the desired flat-sided flagstone or blocks. <br /> The rock is composed mostly of well-sorted quartz grains cemented by silica, which <br /> make the rock extremely hard. The term"well sorted" means all the grains are about the <br /> same size. The surfaces of the grains are frosted due to multiple collisions with adjacent <br /> grains during transport by wind. In contrast, quartz grains deposited by water process, <br /> such as in rivers and streams, are polished. Most of the rock in Meadow Hollow Quarry <br /> is light yellowish-tan or blond color, but is locally reddish or orange due to oxidation of <br /> trace amounts of iron. In a few places, branching black fem-like patterns (known as <br /> dendrites) cover rock faces. These features are composed of pyrolusite (Manganese <br /> Oxide) and are inorganic. <br /> At Meadow Hollow Quarry, the Lyons Formation "dips" (i.e. is tilted) about 15 degrees <br /> east, such that the sloping hillside above the quarry represents the approximate upper <br /> surface of the Lyons Formation. The Lyons Formation lies stratigraphically above a thick <br /> (over 1300 feet)sequence of largely reddish sandstone, shale, and minor limestone(Owl <br /> Canyon, Ingleside, and Fountain Formations deposited during the Permian and <br /> Pennsylvanian Periods). These sediments below the Lyons Formation were shed in <br /> meandering streams along the flank of a long-eroded mountain range. The 500-foot <br /> thick Lykins Formation underlies the valley(Meadow Hollow) immediately to the east of <br /> the quarry. The easily eroded Lykins consists mostly of reddish shale, sandstone, and <br /> minor algal limestone deposited in slow-moving rivers and lakes. <br /> Images D-3 through D-7 below show a summary and detail of the subsurface stratum of <br /> the Affected Land and its geologic environs. <br />