Laserfiche WebLink
1 <br />and chart. Yellowish-orange sandy ironstone concretions." <br />The lower part of the Laramie Formation is described as <br />"almost entirely yellowish-gray ironstained and white 'salt and <br />' pepper' friable sandstone composed of quartz, biotite mica and <br />' kaolinized feldspar. Sandstone 110 feet thick at base is <br />considered Fox Hills Sandstone by one authority. Gray sandstone <br />' contains gray shale chips. Contains thin ironstone layers and <br />shale layers near base. Sub-bituminous coal beds as thick as 8 <br />' feet lie in the lower 200 feet above basal sandstone. Abandoned <br />' coal mines are areas of potential subsidence, as in the valley <br />south of Alameda Parkway. Gray or white claystone in beds more <br />' than 10 feet thick is used for manufacture of brick and tile. <br />Contains fossil leaves, wood and other plant remains." <br />The Laramie Formation varies in thickness and consists of <br />1 several coal and clay or claystone layers occurring between the <br />sandstone layers. Small amounts of these sandstone layers can be <br />' mined with the clay, so the smaller strata of sand will sometimes be <br />blended into the clay. The larger strata of sand are generally used <br />' as spoil. <br />The Fox Hills Sandstone (Upper Cretaceous Age) lies below the <br />1 Laramie Formation and presently furnishes the majority of the sand <br />' needs for the operator's brick plants. The Arapahoe Formation <br />(also Upper Cretaceous Age) occurs above the Laramie Formation. <br />' No clays, shales or claystones from this latter formation are <br />being used by the operator. <br />' Clays that burn buff and red are mined from the Laramie <br />' Formation. Generally, the buffs are obtained from the Lower <br />i~ a <br />