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<br />The stream valleys overlying the existing New Elk Mine workings do not <br />appear to be fault-controlled. No extensive faults were encountered in <br />the mine workings under the 14iddle Fork of the Purgatoire River, Pete <br />Canyon, or Apache Canyon. <br />Other than that encountered in conjunction with a significant water flow <br />in the Second Right entries, no faulting has been encountered in the <br />Golden Eagle workings. <br />Rock units in the Raton Basin range in age from Precambrian to <br />Qua rternary. The stratigraphy of the study area consists of the Trinidad <br />Sandstone, the Vermejo Formation, the Raton Formation, and the Poison <br />Canyon Formation. <br />The Trinidad Sandstone is the oldest and deepest of the sedimentary <br />formations listed above. The Cretaceous aged Trinidad Formation is a <br />massive intertongued sandstone which is an important marker strata in the <br />Raton Basin. The sandstone is fine to very fine-grained, light gray to <br />buff in color, and is slightly arkosic. The Trinidad Sandstone reaches <br />thicknesses of 250 feet in the general area and is a prominent cliff <br />former. This sandstone is separated from the coal seams by up to 900 <br />feet of interbedded shales, siltstones, and sandstones. <br />The Cretaceous Vermejo Formation conformably overlies the Cretaceous <br />Trinidad formation. Typically, the Vermejo Formation consists of three <br />lithologies; slightly arkosic sandstone, carbonaceous shale, and coal. <br />The Vermejo rapidly thickens west of the town of Cokedale to over <br />300 feet. <br />The Cretaceous to Paleocene aged Raton Formation is exposed at the <br />surface in the study area. It rests unconformably above the Vermejo <br />Formation and has a total thickness of 1,200 to 1,600 ft. The base of <br />the Raton Formation consists of a buff to gray pebble conglomerate a few <br />inches to several feet in thickness. Most of the Raton Formation is <br />composed of very fine to medium grained sandstones including arkose, <br />orthoquartzite and graywacke which are interbedded with gray to dark gray <br />siltstone and shale. The upper 100 to 200 feet of the formation tends to <br />contain coarse grained, arkosic sandstones and light colored shales. <br />The coal seam which is being mined at the Golden Eagle Mine is the <br />Maxwell seam; the New Elk Mine is located in the Allen seam. Both the <br />Allen and Maxwell seams are located in the middle of the Raton Formation <br />of Cretaceous age. The Allen seam lies stratigraphically beneath the <br />Maxwell coal seam. The seams are separated by a thin interburden strata <br />which varies in thickness from a few feet in the New Elk Mine to a few <br />tens of feet in the Golden Eagle Mine. <br />The Paleocene Poison Canyon formation unconformably overlies the Raton <br />Formation and has a thickness of approximately 600 feet in the study <br />area. It occurs as small isolated outcrops, probably no thicker than <br />200 feet near the study area. This formation consists of massive, very <br />coarse arkosic sandstone, pebble conglomerates, and thick shales. <br />-12- <br />