摘要
大城勘查区含煤地层煤层层数多,厚度、间距变化大,煤层分叉现象较普遍,煤岩层对比是需要解决的重点问题之一。通过对比大城勘查区120余孔自然伽马测井资料,对其特殊层段辅以测井曲线响应特征、层间距变化规律以及标志层岩性与物性对应关系等进行了分析。结果表明,本区基岩顶部、煤系底部自然伽马异常分界明显;6煤组具有"塔松"异常形态特征反映;5煤层"剑指"形态与8煤组"凹状"形态特征显著等。根据自然伽马曲线的典型特征对本区的煤岩层位进行了对比,确定了煤系基底、基岩界面的基本形态,厘清了5煤、6煤8煤9煤等层位的关系。特别是在局部层位发育不全、煤层归位较困难时,通过形态特征跟踪,较为准确的识别了层位及其分叉合并关系。
Coal-bearing strata in the Dacheng exploration area have characteristics of muhiple coal seams, variable coal thickness and interval, bifurcation of coal seam is common, so that coal seams and rocks correlation is one of major issues in the area. Through correlation of gamma-ray logging data from 120 more boreholes in the area, carried out analyses of special sector logging trace response char- acteristics, interval variation pattern, and marker lithologic and physical properties correspondence etc. The result has shown that on bedrock top and coal measures bottom, the gamma-ray demarcation abnormal traces are apparent; coal group No.6 has ＂deodar＂, coal No.5 ＂sword fingers＂ and coal group No.8 ＂concave＂ abnormal pattern reflections. Based on gamma-ray traces typical characteristics carried out correlation of coal and rock horizons in the area. Thus determined basic configuration of coal measures basement, bedrock interface; clarified horizon relationship between coal Nos.5, 6, 8 and 9. Especially when local horizon is incompletely developed, coal seam difficult to attribution can through configuration characteristic tracing, more accurately identified their horizon and bifurcation, merging relations.
出处
《中国煤炭地质》
2016年第6期78-82,共5页
Coal Geology of China
关键词
自然伽马异常
地层划分
物性标志
煤层对比
gamma-ray anomaly
stratigraphic subdivision
physical property index
coal seams correlation
