中朝与扬子地块结合带东部的卫星重力异常特征研究  

Characteristics of satellite gravity anomalies in the eastern boundary belt between Sino-Korean and Yangtze blocks

作　　者：金峰男[1,2] 杜劲松[2] 陈超[2] 

机构地区：[1]朝鲜沙里院地质大学地球物理系,北黄海郡沙里院市 [2]中国地质大学(武汉)地球物理与空间信息学院,武汉430074

出　　处：《地球物理学进展》2010年第4期1219-1232,共14页Progress in Geophysics

摘　　要：中朝板块与扬子板块碰撞结合带过黄海向东延伸方式一直是国内外学者关注的问题.本文采用最新的地球重力场模型(GGM03C)计算了中国东部海域及朝鲜半岛的360阶卫星布格重力异常,通过异常分离、水平梯度及其垂直导数等位场资料处理和边界识别技术的应用,获得与研究区地块边界及断裂相关的各种信息.结合地质资料,对中国东部海域及朝鲜半岛进行地质构造单元划分与断裂系统分析,探讨了中朝与扬子地块结合带在海区位置与东部延伸模式.对京畿地块的深部结构及地质构造的认识是探讨中朝-扬子地块结合带在朝鲜半岛所在位置的关键.分析认为,五莲-青岛-荣城断裂和嘉山响水断裂构成中朝-扬子地块结合带的海区段,南黄海南部断裂带与绍兴勿南沙断裂带构成中朝-华南地块结合带;在京畿地块中部可能存在近南北向的断裂带,与临津江构造带、沃川构造带和上述两个结合带共同构成中朝、扬子与华南地块结合带;南黄海属于扬子地块,而北黄海与朝鲜半岛大部分仍属于中朝地块,其南界位于济州岛南缘断裂带附近,济州岛南缘断裂带南部海域为华南地块.The Dabie-Sulu Orogenic belt formed as the result of the collision of Sino-Korean and Yangtze Plates in eastern China during late Permian and Triassic. The east extension of this Orogenic belt in the Yellow Sea and the Korean Peninsula has been a focal issue at home and abroad in the past decade. Utilizing the up-to-data model（GGM03C） of the earth gravitational field, the satellite gravity anomaly is calculated on the 2~ 360 order for the region（32°-42°, 120°- 130°E） in the Yellow sea and its adjacent area. Using the digital elevation model, we implemented a Bouguer correction to get rid of the affection by sea water and the terrain undulation, and then get various information on the boundary of different geological units and fault systems by trend analysis to separate the gravity anomalies, the horizontal gradient, the vertical direction derivation of horizontal gradient and the vertical derivation of the local gravity anomalies. Based on the geological results, we divide the research region into various geological units and analyze its fault system, and at last, explore the location and extension type of the boundary belt between Sino-Korean Yangtze blocks. The computed results show that the satellitegravity anomalies contain more details than ship-borne gravity anomalies, and we consider that the Wulian-Qingdao- Rongcheng fault and Jiashan-Xiangshui fault constitute the boundary between Sino-Korean and Yangtze blocks in the Yellow sea, the south fault of the South Yellow Sea and Shaoxing-Wunansha constitute the boundary between Yangtze block and South China block. The deep structure of the Kyonggi massif is a key to understand the boundary belt position and extension between Sino-Korean and Yangtze blocks. Besides, there may be a nearly north-south fault zone in the iniddle of the Kyonggi massif, which combines the Imjingang belt and Okcheon bek to constitute the boundary between Sino-Korean and Yangtze blocks in the Korean-peninsula. Therefore, the North Yellow Sea and most part of the Korean pen

关 键 词：中朝地块 扬子地块 结合带 朝鲜半岛 黄海 卫星重力 

分 类 号：P312[天文地球—固体地球物理学]