摘要
综合地球物理探测与研究是地学断面的重要内容和基本依据,本断面的综合地球物理研究表明:这里的地壳可分为上、中、下三层,在某些部位中层地壳可进一步分为两层,其上层在断面东南端的辽河断陷东侧及燕山台褶带的义县、朝阳地区呈现为低速层;地壳厚度在断面东南端薄,为31—35km,而在西北端厚,达38—40km;辽河裂谷东侧存在壳内高导层,整个断面上地幔高导层发育,在辽河断陷及朝阳、义县地区反映为上地幔隆起区,在西拉木伦河一带出现落差达50km左右的台阶;确认析木断裂、郯—庐断裂北段、朝阳—北票断裂、赤峰—开原断裂和西拉木伦河等断裂为壳幔深断裂;发现海城地区、朝阳—北票地区及西拉木伦河地区为地壳与上地幔结构异常区,这里也正是地震较活跃的地区。
Synthetic geophysics exploration and research are the most important content and basis of geoscience transection study. The transection in the case of the paper shows by synthetic geophysics research that the crust is divided into three layers, i. e. , upper, middle and lower one, and the middle layer of some sections is further divided into two one. Crustal thick of southeast section of the transection is 31—35km, and 38—40km at northwest part of the one. There exists a high—conductivhy layer in the east side of Liao River depression area. Upper mantle uplifts appear in Liao River depression area, Chaoyang and Yixian region. Simu fault, North Tanlu fauh, Chifeng—Kaiyuan fault and Xar Moron River fault are confirmed as deep fault to cut off M—discontinuity.
出处
《防灾减灾学报》
1993年第2期1-12,共12页
Journal of Disaster Prevention And Reduction
关键词
地学断面
地壳与上地幔
高导层
低速层
Geoscience transection
Crust and upper mantle
high—conductivity layer
low—velocity layer