川中北部须家河组烃源岩测井解释及评价

Log Interpretation and Evaluation of Hydrocarbon Source Rocks of Xujiahe Formation in the North of Central Sichuan Basin

冯林杰 蒋裕强 曹脊翔 杨长城 宋林珂

FENGLinjie JIANGYuqiang CAOJixiang YANGChangcheng SONGLinke

西南石油大学地球科学与技术学院, 四川 成都 610500 中国石油非常规油气重点实验室储层评价研究室, 四川 成都 610500 中国石油西南油气田公司致密油气勘探开发项目部, 四川 成都 610056 中国石油西南油气田公司开发管理部, 四川 成都 610056

School of Geoscience and Technology, Southwest Petroleum University, Chengdu, Sichuan 610500, China Reservoir Evaluation Laboratory, CNPC Key Laboratory of Unconventional Oil & Gas, Chengdu, Sichuan 610500, China Project Department of Tight Oil and Gas Exploration and Development, Southwest Oil & Gas Field Company, PetroChina, Chengdu, Sichuan 610056, China Management Department of Gas Field Development, Southwest Oil & Gas Field Company, PetroChina, Chengdu, Sichuan 610056, China

基于烃源岩地球化学实验成果和常规测井资料，通过拟合地球化学参数敏感测井值，建立了可靠性较高的总有机碳含量以及生烃潜量测井解释模型，同时结合研究区实际，制订了相应的烃源岩分级评价标准，并对其平面展布进行了初步刻画，结果表明： 1）川中北部须家河组烃源岩在测井曲线上具有高自然伽马，高声波时差，较高电阻率以及低补偿密度响应特征； 2）声波时差和电阻率曲线对烃源岩总有机碳含量、生烃潜量的响应较为敏感，基于二者与实测地球化学参数间的多元回归，可以得到较为可靠的烃源岩总有机碳含量以及生烃潜量解释模型； 3）研究区须家河组烃源岩总有机碳含量多在0.75%~1.50%，生烃潜量多在0.60~1.00 mg/g，以差烃源岩为主； 4）纵向上，须五段是本区须家河组烃源岩发育的主力层段，其次为须二段；平面上，须五段烃源岩厚度具有自西向东减薄的趋势，而须二段烃源岩厚度呈北西至南东向减薄。

Based on the geochemical experiment results and logging data of source rocks, by fitting the sensitive logging values of geochemical parameters, a reliable logging interpretation model of total organic carbon content and hydrocarbon generation potential is established. At the same time, combined with the actual situation of the study area, the corresponding hydrocarbon source rock classification evaluation standards are formulated, and their plane distribution is preliminarily characterized. The results show that: 1) the source rocks of the Xujiahe Formation in the northern of central Sichuan Basin have high natural gamma, high acoustic transit time, high resistivity, and low compensation density response characteristics on logging curves; 2) the response of acoustic transit time and resistivity curves to the total organic carbon content and hydrocarbon generation potential of source rocks is relatively sensitive. Based on multiple regression between the two and measured geochemical parameters, a more reliable interpretation model for the total organic carbon content and hydrocarbon generation potential of source rocks can be obtained; 3) the total organic carbon content of the source rocks of the Xujiahe Formation in the study area is mostly 0.75% to 1.50%, and the hydrocarbon generation potential is mostly 0.60 mg/g to 1.00 mg/g, mainly composed of poor hydrocarbon source rocksl; 4) vertically, the Xu5 Member is the main source rock development zone of the Xujiahe Formation, followed by the Xu2 Member; Horizontally, the thickness of the source rock in the Xu 5 Member has a trend of thinning from west to east, while the thickness of the source rock in the Xu 2 Member has a trend of thinning from northwest to southeast.

10.11885/j.issn.1674-5086.2021.09.22.01