黄海中央断裂带的地球物理证据及其与边缘海演化的关系  

GEOPHYSICAL EVIDENCES FOR THE CENTER FAULTS IN YELLOW SEA ANDTHEIR RELATIONSHIP WITH EVOLUTION OF MARGINAL SEAS

作　　者：郝天珧[1] Suh Mancheol 阎晓蔚[1] 江为为[1] 宋海斌[1] 胥颐[1] 刘振峰[1] 

机构地区：[1]中国科学院地质与地球物理研究所,北京100101 [2]韩国公州大学地质资源系

出　　处：《地球物理学报》2003年第2期179-184,T004,T005,共8页Chinese Journal of Geophysics

基　　金：国家自然科学基金资助项目 (40 0 740 2 1 );国家基础研究 973资助项目 (G2 0 0 0 0 4 67- 0 1 );韩国KOSEF项目 (996 - 0 4 00- 005-2).

摘　　要：根据黄海及周边地区的布格重力资料 ,通过解析延拓、目标场提取、任意水平方向导数计算、离散小波变换等处理 ,得到各种有关断裂的信息 .经过与地震层析成像结果和地质资料的综合分析 ,认为黄海中央断裂带是一组“X”型交叉断裂而不仅仅是一条NW向延伸的断裂 ,并提出了有关的地球物理证据 .经分析认为 :黄海中央断裂带的存在是造成黄海东西两侧在地球物理场面貌、断裂分布特点与规模上有较大差异的原因之一 .由于该断裂带的存在 ,致使郯庐断裂带的右旋活动所产生的应力对黄海东西两侧的影响不一致 ,因而产生了黄海西部重力异常等值线凌乱、密集、断裂密布但规模相对东部较小的现象 .认为黄海中央断裂带受扬子块体向中朝块体嵌入过程的影响 ,形成一组近SN向为锐角的“X”断裂带 ,但该断裂带具有明显多期活动的迹象 ,不仅与特提斯体制下块体碰撞、俯冲作用有关 ,也与后期太平洋板块向欧亚板块的聚敛、俯冲作用有关 .In light with Bouguer gravity data, various information on faults were obtained after the processing (upward, arbitrary horizontal direction derivative, wavelet transform etc.). It is shown that the Center Faults in Yellow Sea are 2 faults instead of one fault in NW direction. The geophysical evidences are shown after comprehensive analysis on gravity, tomography result and geological information. We believe that existence of the Center Faults in Yellow Sea is of reasons for the differences on geophysical field , distribution and size of faults. Stress from dextrorotation activity of Tanlu Fault brings different effect to the west and east parts of Yellow Sea because of the existing of the Center Faults in Yellow Sea. Isolines of gravity in the west part of Yellow Sea are dense but the size of gravity anomaly is less than in the east part of Yellow Sea. The sharp angle in SN direction of “X”—sharp faults in one group were formed during the inset process from Yangtze block to Sino-korean Bolck. The center fautls in Yellow Sea show the active evidences in different time. They are related not only with block collision in Tethyan System but also with subduction afterward from Pacific Plate to Euro-Asia Plate.

关 键 词：黄海 中央断裂带 “X”型交叉断裂 地球物理场特征 多期活动 

分 类 号：P313[天文地球—固体地球物理学]