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indicative of the quality as well as the thickness of the coal <br />• seam, A good quality coal (i.e., low ash content and higher BTU <br />value) is indicated when the natural gamma and gamma gamma density <br />curves are low and the resistivity curve is high. Relative <br />position changes of these curves through the coal seam indicate <br />changes in the quality of the seam. For example, a higher natural ~ <br />gamma curve indicates an increase in the ash content of the coal <br />and thus a lower BTU value. Also, a lower resistivity curve indicates <br />greater conductivity due to the presence of impurities in the seam, <br />thus lowering the BTU value. A higher or an erratic density curve <br />again indicates the presence of higher ash zones or partings in the <br />seam which lowers the BTU value cf the coal. <br />In analyzing the electric logs and core analysis data to <br />determine the mineable coal thickness for the isopach map, it is <br />evident that the quality of the lower portion of the seam in Pit 2 <br />is much poorer than that of the upper portion. This trend is true <br />for every hole which was cored in the vicinity of the nose of the <br />• anticline (Table 7 is a summary of the as received data). This <br />poorer quality in the lower portion of the seam, as exhibited by <br />the cores, is also evident on the electric logs of the core holes. <br />The sample electric log of core hole number LM1C-SC (Exhibit C-8) <br />shows that the upper ten feet of the coal averages about 10,200 <br />BTU while the lower five feet is only 8,600 BTU. The resistivity <br />curve correspondingly indicates relatively high resistivity through <br />the upper ten feet of the coal, while in the lower five feet there <br />is a pronounced drop in the resistivity. The natural gamma curve <br />for the upper ten feet shows very low natural radioactivity, while <br />the bottom five feet shows a corresponding increase in ash content <br />and thus lower BTU value. Therefore, as can be seen from the log, <br />although there is fifteen feet of "seam" present, only ten feet is <br />economically recoverable due to quality considerations. <br />All other electric logs for which there were not cores for <br />• analyses are similarly interpreted utilizing the decrease in <br />resistivity and increase in natural gamma to arrive at the drilled <br />-z9- <br />