摘要
本文重点综述了70年代末以来,国外开展的利用与油气相关的成岩作用磁性矿物与微磁异常对应关系进行磁法直接找油方法的进展。结合笔者“七五”期间完成的相同领域的科学研究,评述了方法的应用效果。结果认为,由深部油气藏中的烃向上微渗漏在近地表岩层中形成的还原作用产生的成岩作用磁性矿物的地质-地球化学模型可以成立。成岩作用磁性矿物在地面上方可能产生高频、低幅度(一般小于20nT)的微磁异常。含油气区沉积盖层中分布的成岩磁铁矿具有典型球粒状的特有矿物形貌标志,它们携带了较为稳定的化学剩磁(CRM)。浅层土壤的磁性与烃含量之间呈明显的相关特征。结合沉积盖层及浅层土壤的磁性、矿物及地球化学成分建立含油、气区地磁-地化相关模型,可能是利用磁法直接找油的一种全新的油气预测新方法。
This paper summarizes the main advance of direct magnetic location of oil and gas abroad since the late 1970' s using the relationship between diagenetic magnetic minerals and microseepage within oil and gas , and reviews the results of application of this method along with the author' s results obtained in the same study during 1986-1990. Results show that the geological-geochemical model of diagenetic magnetic minerals originated from hydrocarbon seeping upwards under reduced condition in near-surface rocks can be set up. Diagenetic magnetic minerals can generate micromagnet-ic anomalies of high-frequency and low magnitude (less than 20nT) above the ground. Diagenetic magnetites within sedimentary cover strata over oil or gas field are present primarily as spherical crystal aggregates that usually carry stable chemical remanent magnetization (CRM). Magnetism and hydrocarbon content of shallow soil show interrelated characteristics. The geomagnetic-geochemical model of oil and gas field based on magnetism of sedimentary cover strata and shallow soil along with mineral and geochemical composition may be a new method for oil and gas prediction.
出处
《地质科技情报》
CAS
CSCD
北大核心
1991年第4期89-95,共7页
Geological Science and Technology Information
