测井曲线在杭东勘查区煤炭普查煤岩层对比中的应用

杭东普查区煤层产状平缓，构造简单，但由于含煤地层为陆相沉积，煤层层数多、厚度、间距变化大，沉积岩相变化快、大范围内缺乏稳定的对比标志层，因此煤岩层对比是本区勘查需要重点解决的难题。通过对比杭东普查区与邻区200余孔的测井资料，分析煤岩层在各种测井曲线的异常特征与异常组合规律，确定了对煤岩层对比有重大意义的标志层，如延长组与上覆延安组的典型视电阻率异常分界；延安组在高视电阻率曲线上的“树杆”状凸起特征；安定组视电阻率曲线近直线的低值形态；4-1煤在视电阻率曲线上呈现出的“斜坡”状或“刀”状高异常，以及在自然伽玛曲线上的“凹坑”特征；侏罗系中统直罗组的高伽马异常，等等。这些典型特征保证了该区煤岩层对比可靠性，为提交优质地质勘查报告发挥了重要作用。

Application of Logging Traces on Coal Seams and Strata Correlation in Hangdong Exploration Area Coal Prospecting

Coal seams in the Hangdong prospecting area have gentle occurrences and simple structures, but because of coal-bearing strata are continental deposits, multilayered coal seams, large thickness and interval changes, quick sedimentary facies variation, lack of stable correlation marker beds over a vast area, thus the coal seams and strata correlation is a hard nut need to be solved in the pros- pecting area. Through the contrast of Hangdong prospecting area and neighboring areas 200 more logging data, analyzed coal seams and strata anomalous features and combination pattern on various logging traces, determined marker beds have great significance in coal seams and strata correlation. They have typical apparent resistivity anomaly interface between Yanchang Formation and overlying Yanan Formation; ＂trunk typed＂ dome up characteristics of Yanan Formation on high apparent resistivity traces; Anding Formation near straight line low value configuration on apparent resistivity traces; coal seam No.4-1 presented ＂slope＂ or ＂knife＂ shapes on ap- parent resistivity traces, and ＂pot holes＂ on gamma-ray traces; as well as middle Jurassic Zhiluo Formation high gamma anomalies etc. All of these typical features ensured reliability of coal seams and strata correlation in the area and played an important role in high qual- ity geological exploration report submission.