自生磁铁矿与烃的富集及运移之间相互关系的研究  

A STUDY OF THE RELATIONSHIP BETWEEN THE MAGNETISM OF AUTHIGENIC MAGNETIC MINERALS AND HYDROCARBON MIGRATION

作　　者：刘庆生[1] 张昌达[1] 曲赞[1] 蔡振京[2] 

机构地区：[1]中国地质大学物探系 [2]地质矿产部航空遥感中心

出　　处：《地球科学（中国地质大学学报）》1991年第5期565-571,共7页Earth Science-Journal of China University of Geosciences

基　　金：地质矿产部七.五期间部控局管项目"第二代航空物探寻找油气田的方法技术应用研究"的部分内容。

摘　　要：笔者通过测定位于鄂尔多斯盆地西部和东部两个合气构造上的 k井”与 旧井”钻孔岩心的磁性参数、酸解烃、岩心中磁性矿物的形貌及成分,并与不合油气的“岳参1井”钻孔岩心测试结果进行了对比,认为会气构造中生气岩及盖层岩石主要呈亚铁磁性与顺磁性或反磁性状态,岩石磁性参数值与烃富集程度及运移密切相关.“BI井”6号样品中发现的典型球状磁性矿物是在烃聚集的地球化学环境中形成的自生磁铁矿.球粒表面显示的定向排列微观结构是生物降解作用形成的细菌磁铁矿所致.而不会油气的“岳参1井” 岩心中分离出的片状磁性矿物为钻头脱落的工业铁.The producing gas rock and cover strata indicate special magnetic characteristics, and they consist of the ferrimagnetism, paramagnetism and antimagnetism on the basis of measuring compositions and shape of magnetic mineral within cores of two gas-bearing structures and their acidated hydrocarbon content and magnetic parameters from A well-1 and B well-1 in Ordos Basin and comparing with the results of Yueshen well-l of no oil and gas. They are obviously different from magnetic characteristics of no oil and gas structural rocks, and magnetic parameter values (e.g. susceptibility K, saturation magnetization Js, saturation isothermal remanence J ) are closely felated to the degrees of hydrocarbon enrichment and its migration. The spherical magnetic mineral grains within sample 6 from B well-1 are authigenic magnetite which formed under geochemical conditions of hydrocarbon migration. The microtexture of oriented alignment at the spherical magnetite surface is an indicator of bacterical magnetite due to biodegra-tion, but sheet-like magnetic minerals in cores of Yueshen well-1 are industrie irons of well cutting. These results are the basis of formed geomagnetic-geochemical model of hydrocarbon migration in oil and gas field. It is of important significance in the mechanism study of search for oil directly with magnetic method.

关 键 词：自生磁铁矿 烃 富集 含油气构造 

分 类 号：P618.130.1[天文地球—矿床学]