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• thick. The sandstone is interbedded with brown siltstone and mudstone <br />having occasional plant casts. No definite contact is observable in <br />field, contact placed where coarse clastics predominate over fine <br />grained sediments. Carbonaceous shales are absent above this horizon, <br />and sandstones are generally coarse to very coarse grained in contrast <br />to Raton Formation sandstones. Massive channel sandstone have been <br />mapped as individual units where feasible. <br />Raton Formation Undifferentiated (TKrv). This mapping unit cronsists of <br />interbedded sandstone, siltstone, mudstone, silty shale, carbonaceous <br />shale, and coal. Dominate channel fill sandstone lithology is buff, <br />fine to medium grained, moderately wall to well sorted, subangular to <br />subround, feldspathic to arkosic with feldspars altered to clay; <br />occurring in lenticular, massive resistant beds up to 30 feet thick; <br />internal structures include trough cross-stratification and soft <br />sediment slump features. Laterally extensive along direction of <br />sediment transport but abruptly discontinuous normal to channel axis. <br />• Mapped as individual units where possible. Other sandstone lithologies <br />not differentiated during mapping are very fine to fine grained, <br />subangular, feldspathic and cac~ctonly interbedded with siltstone and <br />shale. Siltstones are gray to brown, argillaceous, moderately hard and <br />show rapid lateral and vertical discontinuity. Mudstones are cc~mm~ly <br />brorm to gray, poorly fissile, have an irregular blocky fracture, and <br />variable silt content. Shales are grey to black, locally carbonaceous <br />in thin beds, and often silty and compact. One thin dull, dirty coal <br />bed is present in map area. Individual lithologies not differentiable <br />due to scale and degree of lateral and vertical heterogenity. <br />Lithologies were described at thirteen (13) station locations <br />throughout the RDA, see Table 6, Lithologic Descriptions for the RDA. The <br />stations are shown on Map 6, Surface and Bedrock Geology (Refuse Area). <br /> <br />2.04-13 <br />