基于重磁场特征的松辽盆地基底岩性研究  

Distribution of Basement Lithology in the Songliao Basin Derived from Gravity and Magnetic Anomalies

作　　者：吴真玮 曾昭发[1] 李静[1] 赵雪宇[1] 许天福[2] 

机构地区：[1]吉林大学地球探测科学与技术学院,吉林长春130026 [2]吉林大学环境与资源学院,吉林长春130026

出　　处：《地质与勘探》2015年第5期939-945,共7页Geology and Exploration

基　　金：国家863项目(2012AA052801);博士点基金项目(20130061110060)联合资助

摘　　要：盆地的基底埋藏深度、岩性和断裂分布与地热资源的形成、分布和开发利用密切相关。本文基于重磁方法的特点和松辽盆地的重磁场异常,利用最佳向上延拓的方法进行场源分离,提取了基底重磁异常信息;依据不同岩石物理属性(密度和磁性)和重磁异常对应分析的结果,对松辽盆地的基底岩性分布进行了划分,其结果对盆地地热资源远景评价和开发利用有重要参考价值。The basement burial depth,lithology and fault distribution of a basin are closely related to geothermal resources. Based on the characteristics of gravity and magnetic anomalies,using the preferential upward continuation method,this work has separated the fields and sources of gravity and magnetism,and extracted the gravity and magnetic anomalies of the basement in the Songliao basin. Combining physical properties of rocks,correlation between gravity and magnetic anomalies as well as geological data,this work has further inferred the lithological distribution of the basement in the Songliao basin. Metamorphic and igneous rocks dominate the basin basement,which were formed in the Caledonian,Hercynian,Indosinian,and Yanshanian periods. The rocks of former two ages are relatively older,while those of the latter are younger. The Indosinian and Yanshanian igneous rocks are distributed in the central and eastern basin,Hercynian rocks in the middle and west,and few Caledonian granites in the west. Their patterns are controlled by faults in the basement. Strikes of these rock bodies tend to be parallel to the basin boundaries and faults within the basin. Magma activities along faults of the basement likely determined the distribution of the lithology. These data will provide evidence for prospect assessment and development of geothermal resources in the basin.

关 键 词：地热 重磁异常 松辽盆地 对应分析 基底岩性 火山岩 

分 类 号：P631[天文地球—地质矿产勘探]