测井评价烃源岩的方法及其应用效果

烃源岩评价是地质综合评价的基础，因其需要依据大量分析化验资料，而常常受到经费和样品来源的困扰。文中提出一种在陆相地层依据测井资料评价烃源岩的方法：利用重叠法把刻度合适的孔隙度曲线（如声波时差曲线）叠加在电阻率曲线上，在饱含水但缺乏有机质的岩石中，两条曲线彼此平行并重合；在含油气储集岩或富含有机质的非储集岩中，两条曲线之间存在差异，可根据两条曲线的差异及曲线的变化情况判识和评价烃源岩。应用效果证明，此方法简单易行，能够较准确地评价每口井的烃源岩总厚度、各层烃源岩的深度分布，可以定性评价烃源岩等级，大致确定生油门限深度，还可以对烃源岩的区域分布规律作出评价。图4表4参1（张志伟摘）

A method of source rock evaluation by well-logging and its application result

Source rock evaluation is the bassis of geologically comprehensive evaluation. It is always bothered by lack of funds and rock samples.This paper suggests a evaluation method of source rocks in a continental basin by well-logging records. Suitably calibrated porosity curve (such as acoustic interval transit time log curve) is superimposed on a resistivity log curve. Two curves may be parallel and concide each other in case of rock formation which are water saturated but lack of organic matters. In case of oil/gas reservoir rocks or non-reservoir rock but containing abundant organic mattere, difference between two curves am be observed. Source rocks can be identified and evaluated by such differences of these two curves and their variations. Results of application show that this method is simple and feasible. It can evaluate the total thickness of source rocks and the vertical depth of their distribution rather correctly. It can be used to evaluate the total thickness of source rocks in each well and the depth of cach source bed, grade the are rocks, determine approximately the threshold depth of hydrocarbon generation, and evaluate the areal distribution of source rocks as well.