用地震反射剖面研究汤阴地堑上地壳结构与断裂特征  

Study on the Upper Crustal Structure of Tangyin Graben by Seismic Reflection Profiles

作　　者：花鑫升[1] 酆少英[1] 姬计法[1] 石金虎[1] 赵成彬[1] 秦晶晶[1] 李吉昌[1] Hua Xinsheng;Feng Shaoying;Ji Jifa;Shi Jinhu;Zhao Chengbin;Qin Jingjing;Li Jichang(Geophysical Exploration Center,China Earthquake Administration,Zhengzhou 450002,China)

机构地区：[1]中国地震局地球物理勘探中心,郑州450002

出　　处：《震灾防御技术》2020年第4期811-820,共10页Technology for Earthquake Disaster Prevention

基　　金：国家自然基金(41674140)。

摘　　要：汤阴地堑位于太行山脉与华北平原的过渡带,是太行山前重要的地质构造单元。为研究汤阴地堑上地壳结构和断裂特征,利用安阳市与新乡市活断层探测获得的深、浅地震反射剖面,结合研究区已有地震、地质资料,对汤阴地堑浅部结构、汤东断裂特征进行分析研究。结果表明,汤阴地堑北部与南部地壳结构差异明显。地堑北部是由汤东断裂控制的半地堑,地堑内反射震相丰富、反射波层组关系清晰,多组新生代、古生代沉积层强反射不整合地覆盖在自西向东倾伏的结晶基底反射Tg上,且随着深度增加,地层倾角增大,显示出明显的多期掀斜运动特征。地堑南部表现为由汤东、汤西断裂共同控制的断陷型地堑,地堑内新近系底界面反射波TN自西向东倾伏,其下为一些横向呈水平或东倾、延续性较短的反射震相。地堑南部与北部不同的反射震相特征表明,测线控制区域内的汤阴地堑沉积环境与运动特征可能有所差异。汤东断裂为走向NE,倾向NW的铲型正断层,汤西断裂为走向NE、倾向SE的正断层,北部中深层地震反射剖面上未发现该断层的存在。Tangyin graben,located in the transitional zone of the Taihang mountains and the North China plain,is a key geological structure unit of Taihang piedmont.In order to find out the upper crustal structures,the fault structure characteristics of Tangyin graben,we applied the deep and shallow seismic reflection profiles of active fault exploration in Anyang City and Xingxiang City.Based on the deep and shallow seismic reflection profiles and the geological and seismic data available in the study area,the shallow structure of Tangyin graben and the structural characteristics of Tangdong fault are analyzed and studied.The results show that the shallow crustal structures in the north and south of Tangyin graben are obviously different.the northern part of the graben is a semi-graben controlled by Tangdong faul.the graben internal reflection seismic phase is rich,and reflection layer group relations is clear.several group of strong reflection waves from Cenozoic to Paleozoic sediments uncomfortably cover the crystalline basement reflection Tg dipping from west to east,and the dip angle of stratum increases with the increase of depth.the graben shows obvious multi-period tilted movement characteristics.The southern part of the graben is a faulted graben controlled by the Tangdong and Tangxi faults,the reflected wave T_(N) at the Neogene bottom interface dips from west to east,and there are some reflection phases with horizontal or Eastern dips and short reflection phase below TN.On the whole,The different characteristics of reflected seismic facies in the south and north of the graben indicate that the sedimentary environment and movement characteristics of the Tangyin graben may be different in the area controlled by the survey line.The Tangdong fault is a shovel-type normal fault striking NE and trending NW.The Tangxi fault is a normal fault striking NE and trending NW,and no fault is found in the mid-deep seismic reflection section of the Northern Tangyin graben.

关 键 词：汤阴地堑 汤东断裂 地震反射剖面 浅层地震勘探 

分 类 号：P542[天文地球—构造地质学] P315.2[天文地球—地质学]