中国南海北部潮汕坳陷NHC-1测线及邻区重磁场特征与地壳结构  

The Characteristic of Gravity-Magnetic Fields and Crust Structure of NHC-1 Survey Line and Its Adjacent Area at Chaoshan Depression in North of the South China Sea

作　　者：孟令顺[1] 杜晓娟[1] 刘万崧[1] 孙建国[1] 张凤旭[1] 王雪秋[1] 梁铁成[1] 张志荣[2] 

机构地区：[1]吉林大学地球探测科学与技术学院,长春130026 [2]广州海洋地质调查局,广州510000

出　　处：《吉林大学学报（地球科学版）》2006年第5期851-855,868,共6页Journal of Jilin University：Earth Science Edition

基　　金：国家"863"项目(2003AA611010-01/2)

摘　　要：利用中国南海北部潮汕坳陷内首次获得的一条长250km的重磁剖面数据,研究了潮汕坳陷地壳结构,定性分析了火山岩的分布及其属性。采用欧拉反褶积方法估算了重力场源的位置及其深度,划分出陆坡北缘及东沙两个断裂带。根据断裂带切割深度,认定这两个断裂带均为超壳断裂,且都有岩浆上涌。应用Parker-Oldenburg法反演计算了莫霍面深度。用滑动对数能谱分析和人机交互正反演方法计算出磁性基底深度。结果表明:潮汕坳陷莫霍面从西北方向测线起始点的25km向东南方向抬升到终点的14km,而磁性基底埋深从西北测线起始点的3.6km向东南方向逐渐加深到测线终点的8.9km。About 250 km gravity--magnetic profile data were obtained in Chaoshan depression in the Northern part of southern China sea for the first time. The crust structure of Chaoshan depression was studied, the distributions and attributes of the volcanic rock was analyzed qualitative. Based on Euler deconvolution, the position and depth of the source of gravity fields was estimated, the northern margin faults of continental slope and Dongsha faults was divided. According to dissecting depth of the zone of faults, the two zones of faults with upwelling of magma were transcrust （crust-upper mantle zone of faults）. The depth of Moho-surface was calculated by Parker--Oldenburg inversion. Using moving average of logarithmic energy and men-computer mutual system, the depth of magnetic basement was inversed. The results shown that the depth of Moho-surface in Chaoshan depression was uplifted gradually from northwest to southeast direction, the beginning poing was about 25km deep, and the end point was 14 km deep. The depth of magnetic basement was deepen gradually from the start station 3.6 km of the measuring line in northwest direction to the end station 8.9 km of the measuring line in the southeast direction.

关 键 词：中国南海 潮汕坳陷 重磁异常 地壳构造 

分 类 号：P631.1[天文地球—地质矿产勘探] P631.2[天文地球—地质学]