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of the seven horizons are illustrated below by Figure 2, Stratigraphic <br />Column. The total thickness of the Vermejo sequence is approximately <br />700 feet. Thee Vermejo Formation outcrops in Chandler Creek, along <br />the Fawn Hollow Bluff and Colorado State Highway 115. <br />Raton Formation <br />Unconformat~ly overlying the Vermejo Formation are the sediments of <br />the Raton Formation. This unit consists of two members, a basal <br />sandstone and overlying sequence of interbedded mud and <br />sandstones. The basal sandstone is massive, cross-stratified and white <br />to light gray in color with betonitic cementation and extensive rounded <br />to sub angular conglomerate inclusions. The Brook Canon <br />coal seam exists in the lower depths of the formation. The total <br />thickness is approximately 450 feet. <br />The Raton F~~rmation outcrops in the General Area including most of <br />Section 14, eastern portion of Section 15 and west portion of Section <br />13 (west of Chandler Creek). <br />Poison Canv~on Formation <br />Patches of Poison Canyon Formation overlay the Raton Formation in <br />Section 14 and along the Fawn Hollow Bluffs. This formation consists <br />of 200 feet or more of alternating beds of mudstone and sandstone <br />with a basal conglomeratic sandstone. This formation is barren of coal <br />and has been mapped as part of the Raton Formation. Depositionally <br />and physically similar to the Raton, it is difficult to distinguish between <br />.the two formations. <br />Boulder Alluvium <br />Covering most of the topographic ridges and flats are a series of <br />Pleistocene (boulder alluvial deposits. The USGS identified three <br />stratigraphic; horizons of boulder alluviums: the Verdos, the Rocky <br />Flats and the Slocum. The alluviums are not differentiated in mapping. <br />The boulders obscure most of the bedrock outcrops with sheet deposits <br />ranging from 0 to over 40 feet in thickness. The lithology of-the <br />boulders and cobbles are gneiss, schist and sandstone derived from <br />the eroded formations in the Wet Mountains to the West. The boulders <br />and cobbles are bound up in a clay rich soil matrix. <br />C. <br />2.04-10 Revised 5/01/07 <br />