JOINT INVERSION OF GRAVITY, MAGNETIC, SEISMIC DATA OF THE CFT LINE ACROSS THE SOUTHWEST SUB-BASIN AND ADJACENT AREAS AND ITS APPLICATION
-
摘要:
对跨南海西南次海盆及两侧陆缘的1条长达1 093 km，包括海底地震仪(OBS)、长排列多道地震和测深、重力、磁力调查在内的综合地球物理探测剖面(CFT)，进行了重磁震联合反演。基于重磁震联合反演结果，在分段解译的基础上，证实本区多处发育前新生界残余沉积层并发生多期次岩浆活动，南海海域地壳结构颇为复杂，具有陆壳、减薄型陆壳、陆洋过渡壳和洋壳等地壳类型，壳下高速层分布较广。根据以上分析，重磁震数据联合反演是研究海区构造特征和深部地壳结构的重要技术手段。
Abstract:Joint inversion of the 1093 km of integrated geophysical detecting section (CFT) is made across the southwestern sub-basin of the South China Sea and the two sides of the continental margin. The data involved in the inversion includes the ocean bottom seismograph (OBS) data, the long-arranged multi-channel seismic profiles, and the gravity and magnetic profiles. Based on the results of joint inversion and segmented interpretation, many pre-Cenozoic residual sedimentary deposits and multiple periods of magmatic activities are observed. The crustal structure of the South China Sea is quite complex, which includes continental crust, thinned continental crust, continental-oceanic transitional crust and ocean crust. The high-speed layer under the crust is widely distributed. The observations prove that the joint inversion of gravity, magnetism, and seismic data is an effective tool to study the structural characteristics of the sea and deep crustal structures.
-
-
表 1 CFT测线地壳速度结构分层方案
Table 1. Layered scheme of crustal velocity model of the CFT line
陆缘陆壳减薄区 西南次海盆区 速度/(km/s) 层位 速度/(km/s) 层位 1.6～3.5 上部沉积层（N+Q） 3.5～5.5 下部沉积层（E，局部有M） 1.6～3.5 大洋层1 5.5～6.5 上地壳 3.5～6.5 大洋层2 6.5～7.0 下地壳 6.5～7.0 大洋层3 7.0～7.6 壳下高速层 7.0～7.6 壳下高速层 >7.6 上地幔 >7.6 上地幔 
下载: 导出CSV
-
[1] 林珍. 南沙中部海域北康-曾母盆地重磁异常特征及解释[J]. 物探与化探,2003,27(4):263-268.
[2] 林珍,张莉,钟广见, 等. 重磁震联合反演在南海东北部地球物理解释中的应用[J]. 物探与化探,2013,37(6):968-975.
[3] 冯旭亮,张功成,王万银,等. 基于重磁震资料的南海新生代盆地分布综合研究[J]. 地球物理学报,2018,61(10):4242-4254. doi: 10.6038/cjg2018L0567
[4] 龚再升, 李思田, 谢泰俊, 等. 南海北部大陆边缘盆地分析与油气聚集[M]. 北京: 科学出版社, 1997.
[5] 李家彪,丁巍伟,吴自银,等. 南海西南海盆的渐进式扩张[J]. 科学通报,2012,57(20):1896-1905.
[6] 张莉,雷振宇,许红, 等. 南海北部深水区双峰盆地地震层序特征及勘探前景[J]. 海洋地质与第四纪地质,2020,40(1):1-11.
[7] 王先庆,陈升,许兰芳,等. 南海西南次海盆柱状沉积物酸类化合物的地球化学特征[J]. 海洋地质前沿,2020,36(7):17-24.
[8] 张洁. 南海西南次海盆扩张期后岩浆活动及其残留扩张中心的纵横波速度结构[D].杭州: 浙江大学, 2016.
[9] 邱燕,汪俊,阎贫,等. 南海海域地壳结构特征及其构造意义[J]. 南海地质研究,2016(1):1-39.
[10] 邱燕, 王立飞, 黄文凯, 等. 中国海域中新生代沉积盆地[M]. 北京: 中国地质出版社, 2016.
[11] FYHN M B, LARS O B, LARS H N, et al. Geological development of the Central and South Vietnamese margin: implications for the establishment of the South China sea, indochinese escape tectonics and Cenozoic volcanism[J]. Tectonophysics,2009,478(3):184-214. doi: 10.1016/j.tecto.2009.08.002
[12] FRANGKE D, SAVVA D, PUBELLIER M, et al. The final rifting evolution in the South China Sea[J]. Marine and Petroleum Geology,2014,58:704-720. doi: 10.1016/j.marpetgeo.2013.11.020
[13] 郝天珧,黄松,徐亚,等. 南海东北部及邻区深部结构的综合地球物理研究[J]. 地球物理学报,2008,51(6):1785-1796.
[14] 李细兵,吴振利,李家彪. 南海西南次海盆洋中脊分段特征[J]. 海洋地质与第四纪地质,2013,33(3):101-107.
[15] NISSEN S S,HAYES D E,YAO B,et al. Gravity, heat flow, and seismic constraints on the processes of crustal extension: Northern margin of the South China Sea[J]. Journal of Geophysical Research,1995,100(B11):22447-22483. doi: 10.1029/95JB01868
[16] KUDRASS H W,WIEDICKE M,CEPEK P, et al. Mesozoic and Cainozoic rocks dredged from the South China Sea (Reed Bank area) and Sulu Sea and their significance for plate-tectonic reconstructions Geophysical Research[J]. Marine Geology,1986,3:19-30. doi: 10.1016/0264-8172(86)90053-X
[17] SCHLUTER H U,HINZ K,BLOCK M,et al. Tectono-stratigraphic terranes and detachment faulting of the South China Sea and Sulu sea[J]. Marine Geology,1996,130(1):39-78. doi: 10.1016/0025-3227(95)00137-9
[18] 丁航航,丁巍伟,方银霞. 南海西南次海盆基底形态特征及控制因素[J]. 地学前缘,2019,26(3):223-232.
[19] 丁巍伟,陈汉林,杨树锋,等. 南海西南次海盆与东部次海盆地质与地球物理分析[J]. 高校地质学报,2002,8(3):268-279. doi: 10.3969/j.issn.1006-7493.2002.03.004
[20] 林间,李家彪,徐义刚,等. 南海大洋钻探及海洋地质与地球物理前沿研究新突破[J]. 海洋学报,2019,41(10):125-140.
[21] 丘学林,赵明辉,敖威,等. 南海西南次海盆与南沙地块的OBS探测和地壳结构[J]. 地球物理学报,2011,54(12):3117-3128. doi: 10.3969/j.issn.0001-5733.2011.12.012
[22] PICHOT T, DESCLUSE M, CHAMOT R N, et al. Deep crustal structure of the conjugate margins of the SW South China Sea from wide-angle refraction seismic data. Marine and Petroleum Geology[J]. 2014, 58: 627-643.
[23] 吴招才,高金耀,李家彪,等. 南海北部磁异常特征及对前新生代构造的指示[J]. 地球物理学报,2011,54(12):3292-3302. doi: 10.3969/j.issn.0001-5733.2011.12.027
[24] 汪俊, 高红芳, 陈泓君, 等. 基于速度-深度线性模型的时深转换方法及其在南海海盆深水区的应用[J]. 热带海洋学报, 2013, 32(2): 112-117.
[25] 汪俊,邱燕,阎贫,等. 跨南海西南次海盆OBS、多道地震与重力联合调查[J]. 热带海洋学报,2019,38(4):81-90.
[26] 阎贫,刘海龄. 南海北部陆缘地壳结构探测结果分析[J]. 热带海洋学报,2002,21(2):1-12. doi: 10.3969/j.issn.1009-5470.2002.02.001
[27] WANG Y L,WANG J,YAN P,et al. An anomalous seamount on the southwestern mid-ridge of the South China Sea[J]. Acta Geologica Sinica,2017,91(6):2340-2341. doi: 10.1111/1755-6724.13479
[28] 于俊辉,阎贫,郑红波,等. 南海西南次海盆反射莫霍面成像及其地质意义[J]. 海洋地质与第四纪地质,2017,37(2):75-81.
[29] 朱奕先. 基于南海重磁震剖面的地质-地球物理研究[D]. 吉林: 吉林大学, 2019.
[30] 吕川川,郝天珧,丘学林,等. 南海西南次海盆北缘海底地震仪测线深部地壳结构研究[J]. 地球物理学报,2011,54(12):3129-3138. doi: 10.3969/j.issn.0001-5733.2011.12.013
[31] 赵长煜,宋海斌,李家彪,等. 南海西南次海盆NH973-1测线地震解释[J]. 地球物理学报,2011,54(12):3258-3268. doi: 10.3969/j.issn.0001-5733.2011.12.024
[32] YU J H,YAN P,WANG Y L,et al. Seismic evidence for tectonically dominated seafloor spreading in the Southwest Sub-basin of the South China Sea[J]. Geochemistry, Geophysics, Geosystems,2018,19(9):3459-3477. doi: 10.1029/2018GC007819
[33] DING W, SUN Z,DADD K,et al. Structures within the oceanic crust of the central South China Sea basin and their implications for oceanic accretionary processes[J]. Earth and Planetary Science Letters,2018,488:115-125.
-
图(9)
表(1)
计量
- 文章访问数: 1131
- PDF下载数: 122
- 施引文献: 0