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<br />2 coals. This unit is 250 to 300 feet thick and contains the coal beds <br />that are of interest herein. These No. 2~coals are called the Pinnacle <br />and Blacksmith and lie about midway within the Kit unit. The Pinnacle coal <br />varies from 6 to 7 feet thick with a 3 foot rider about 25 feet above <br />and a 3.5 foot lower from 20 to 40 feet below. All three of these seams <br />have been mined at the Grassy Creek Mine. The Blacksmith coal seam lies <br />from 100 to 150 feet below the lower Pinnacle rider. Some mining activity <br />will take place in the Blacksmith seam. Previous mining histories indicate <br />that No, 2 coals and the intervals between them thin and thicken with no <br />predictable pAttern. It is conjectured, therefore, that these coals are <br />"back barrier" and will occur as highly lenticular pods. Kit rocks are <br />beds of shale, coal, sandy shale, and thin sandstones which are tight, lensy <br />and discontinuous. <br />Ki3 rocks outcrop on the west side of the mine area and consist of <br />• No. 3 coals in a sequence of thick, massive sandstones interbedded with <br />thin, soft sandstones and shales. The massive sandstones are light-gray <br />to white, 10 to 40 feet thick and form conspicuous ledges. This sandstone- <br />coal sequence is separated from the Trout Creek sandstone by about 250 feet <br />of sandy shale. Map Units Kil, Kit, and Ki3 are shown on the Geology Map <br />and on the stratigraphic column shown on the following page. The Trout <br />Creek sandstone (Kit) is the most reliable marker bed in the area; it is <br />the top unit of the Iles Formation and is a fine-grained, massive, cliff <br />forming, white sandstone approximately 100 feet in thickness. resting con- <br />formably on the Trout Creek sandstone, to the west outside of the mine area, <br />is the shaley sandy base of the Williams Fork Formation (Kw). This unit <br />is of no interest here but is shown on the map for the sake of completeness. <br />Quaternary alluvia (Qal) related to Grassy Creek drainage has been <br />mapped and is shown on the Geology Map. In the mine area it is for the <br />most part a colluvial mix of slope wash-sluff with alluvial material. It <br />is therefore poorly sorted shale/sand fines with larger sandstone particles. <br />It is restricted to Grassy Creek bottoms and side slopes. Some landslide <br />!~ <br />II.D-3 <br />