烃源岩测井响应特征及定性识别方法——以川东南地区茅一段为例  

Well-logging response characteristics and qualitative identification of source rocks:An example from Maokou 1 Member,southeastern Sichuan Basin

作　　者：程丽 严伟 王昆 CHENG Li;YAN Wei;WANG Kun(Sinopec Exploration Company,Chengdu,Sichuan 610095,China)

机构地区：[1]中国石油化工股份有限公司勘探分公司

出　　处：《天然气勘探与开发》2023年第4期148-153,共6页Natural Gas Exploration and Development

基　　金：中石化科技部项目“四川盆地二叠系海相页岩气富集高产主控因素及目标评价”(编号:P22135)。

摘　　要：利用测井资料快速准确识别烃源岩,是分析评价烃源岩的首要任务。针对川东南地区中二叠统茅口组一段烃源岩地层非均质性强、岩性识别困难的问题,在岩心资料刻度测井资料的基础上,明确了研究区各类烃源岩的测井响应特征,并进一步采用敏感测井曲线的叠合法、交会图法和比值法对烃源岩进行定性识别评价。应用结果表明:①优质烃源岩的测井响应特征主要表现为高声波、高中子、低密度、低电阻率的“二高二低”特征;②敏感测井曲线叠合法和交会图法简单易行,可识别出优质烃源岩,但对于泥质含量较高的烃源岩识别效果较差,利用声波时差与电阻率比值法可以更加快速有效地识别泥质含量相对较高的烃源岩;③通过对研究区3口的测井资料进行处理及岩心对比分析,比值法定性识别各类烃源岩的精度达到92%。Quickly and accurately identifying source rocks through well-logging data is the main thing in source-rock evaluation.The source rocks of Middle Permian Maokou 1 Member in southeastern Sichuan Basin feature strong heterogeneity and difficulty in lith-ological identification.So,for the Maokou 1 source rocks,the logging response characteristics were clarified by using core data cali-brated with logging data.In addition,three methods such as sensitive log superposition,crossplot and ratio were employed for quali-tative source-rock identification and evaluation.Results show that(i)the logging response of quality source rocks is characterized by two-high in acoustic wave and neutron as well two-low in density and resistivity;(ii)among these three methods,superposition and crossplot are simple and easy to do in this identification,but achieving a poor effect in the other source rocks rich in shale content.However,another method of acoustic time to resistivity ratio is a rapid and effective option;and(iii)after logging-data processing and core correlation conducted for 3 wells in the study area,the qualitative source-rock identification accuracy reaches 92%by using the ratio method.

关 键 词：烃源岩 中二叠世 定性识别 叠合法 比值法 四川盆地 

分 类 号：P618.13[天文地球—矿床学] P631.81[天文地球—地质学]