下辽河裂谷型断陷盆地基底的重力解释方法  

GRAVITATIONAL METHOD FOR DETERMINING THE BASEMENT OF LIAOHE RIFTED BASIN, CHINA

作　　者：张建中[1] 戴云[1] 钟本善[1] 

机构地区：[1]成都理工学院

出　　处：《物探化探计算技术》1999年第3期252-256,共5页Computing Techniques For Geophysical and Geochemical Exploration

摘　　要：在利用１∶５０ ０００ 高精度重力资料研究下辽河盆地南部地区的基底构造时，针对该裂谷型断陷盆地基底呈断距较大的破碎断块状格局和盆地下存在上地幔及下地壳隆起的地质构造特点，在分析了布格重力异常成因的基础上， 应用地震测深获得的地壳速度结构和１∶１ ０００ ０００ 的重力资料，成功地划分出深部地质因素产生的背景异常，并合理地进行了异常分离，从而获得了盆地基底和主要密度界面引起的区域异常。然后采用先二维再三维的重力模拟解释思路，确定了盆地基底的深度。The basement of the Liaohe rifted basin consists of small faulted blocks with large throws. Under the basin there is an upfold of upper mantle and lower crust. Using high precision gravity data to research the basement of the basin, the factors producing Bouguer anomaly are analyzed based on the geological and structural features in the study area. The twe dimensional crust velocity structure from seismic sounding and 1∶1 000 000 gravity data are used successfully to get the background anomaly due to deep geological factors. Then the regional anomaly produced by the basement and Neogene subface is obtained with the rational separation of Bouguer anomaly. Moreover, the scheme of gravity modeling from two dimension to three dimension is used, and so the depth of the basin basement in the study area gained effectively.

关 键 词：裂谷型 断陷盆地 基底 异常分离 重力模拟 

分 类 号：P542.3[天文地球—构造地质学] P631.14[天文地球—地质学]