Preliminary analyses of the characteristics of Moho undulation and crustal thinning in East China Sea

Abstract

Abstract: Numerous sedimentary thickness data provided by seismic profiles were collected and drawn into the sedmimentary isopach in the East China Sea. The residual gravity anomalies were obtained by subtracting the gravity effect generated by the sediments from the complete Bouguer gravity anomalies. Depths to the Moho of the East China Sea were inversed from the residual gravity anomalies with constraint of the seismic penetration depths to the Moho. Our results show that depths to the Moho change between 25 km and 28 km gently and crustal thicknesses change between 14 km and 26 km on the East China Sea Shelf, depths to the Moho change between 16 km and 26 km and crustal thicknesses change between 12 km and 22 km within the Okinawa Trough. Crusts at the east of the East China Sea Shelf Basin and the south of Okinawa Trough are thinned evidently, and their crustal stretching factors are up to 2.6 and 3, respectively. Preliminary analyses suggest that the crust of Okinawa Trough is mainly transition type and there is no obvious evidence to prove the existence of oceanic crust.

Key words: sedimentary thickness, depth to the Moho, crustal thinning, East China Sea

CLC Number:

ZHOU Zhi-yuan, GAO Jin-yao, WU Zhao-cai, SHEN Zhong-yan, ZHANG Tao, SUN Yun-fan. Preliminary analyses of the characteristics of Moho undulation and crustal thinning in East China Sea[J]. Journal of Marine Sciences, 2013, 31(1): 16-25.

References

[1] XU Wei-ling, LE Jun-ying. Tectonic movement and evolution of the East China Sea[J]. Marine Geology & Quaternary Geology,1988,8(1):9-21.
许薇龄,乐俊英.东海的构造运动及演化[J].海洋地质与第四纪地质,1988,8(1):9-21.
[2] XU De-qiong, LI Quan-xing, JIANG Jia-zhen. The Mohorovicic discontinuity in the East China Sea and its geologic significance[J]. Marine Science Bulletin,1983,2(5):34-41.
徐德琼,李全兴,蒋家祯.东海莫霍面及其地质意义[J].海洋通报,1983,2(5):34-41.
[3] JIANG Wei-wei, LIU Shao-hua, HAO Tian-yao, et al. Using gravity data to compute crustal thickness of East China Sea and Okinawa Trough[J]. Progress in Geophysics,2002,17(1):35-41.
江为为,刘少华,郝天珧,等.应用重力资料估算东海冲绳海槽地壳厚度[J].地球物理学进展,2002,17(1):35-41.
[4] HAO Tian-yao, XU Ya, XU Yi, et al. Some new understandings on deep structure in Yellow Sea and East China Sea[J]. Chinese J. Geophys,2006,49(2):459-468.
郝天珧,徐亚,胥颐,等.对黄海—东海研究区深部结构的一些新认识[J].地球物理学报,2006,49(2):459-468.
[5] HAN Bo, ZHANG Xun-hua, PEI Jian-xin, et al. Characteristics of crust-mantle in East China Sea and adjacent regions[J]. Progress in Geophysics,2007,22(2):376-382.
韩波,张训华,裴建新,等.东海及其邻域壳-幔结构与展布特征[J].地球物理学进展,2007,22(2):376-382.
[6] GAO Jin-yao, WANG Jun, YANG Chun-guo, et al. Discussion on back-arc rifting tectonics and its geodynamic regime of the Okinawa Trough[J]. Progress in Geophysics,2008,23(4):1 001-1 012.
高金耀,汪俊,杨春国,等.冲绳海槽弧后张裂构造及其动力机制讨论[J].地球物理学进展,2008,23(4):1 001-1 012.
[7] LIN J Y, SIBUTE J C, HSU S K. Distribution of the East China Sea continental shelf basins and depths of magnetic sources[J]. Earth Planets and Space,2005,57(11):1 063-1 072.
[8] GAO Jin-yao. China offshore oceanography-marine geophysics[M]. Beijing: Ocean Press,2013.
高金耀.中国近海海洋-海洋地球物理[M]. 北京:海洋出版社,2013.
[9] Guo Jun-hua. Seismic sequences and the tectonic restoration of the southern Okinawa Trough[D]. Qingdao: Institute of Oceanology,Chinese Academy of Sciences, 2004.
郭军华.冲绳海槽南部地震层序与构造复原[D].青岛:中国科学院研究生院(海洋研究所),2004.
[10] PARK J O, TOKUYAMA H, SHINOHARA M, et al. Seismic record of tectonic evolution and backarc rifting in the southern Ryukyu island arc system[J]. Tectonophysics,1998,294(1-2):21-42.
[11] KONG F C, LAWVER L A, LEE T Y. Evolution of the southern Taiwan-Sinzi Folded Zone and opening of the southern Okinawa trough[J]. Journal of Asian Earth Sciences,2000,18(3):325-341.
[12] LIU Guang-ding. Geophysical field features of China sea and adjacent regions[M]. Beijing: Geological Publishing House,1992.
刘光鼎.中国海区及邻域地质地球物理系列图集[M]. 北京:地质出版社,1992.
[13] ZAI Guang-ming. Petroleum geology of China, Vol.16 Oil &gearing areas on the continental shelf and its neighbouring regions[M]. Beijing: Petroleum Industry Press,1990:445.
翟光明.中国石油地质志卷十六-沿海大陆架及邻海域油气区(上)[M]. 北京:石油工业出版社,1990:445.
[14] ZENG Jiu-ling, WANG Chang-qing, XI Ming-hong. The division of areal structural units and the characteristics of geologic structure of East China Sea[C]. Shanghai: The 5th Petroleum Geological Conference of East China Sea,2004.
曾久岭,王常青,席敏红.东海区域地质构造单元划分及地质结构特征[C].上海:第五次东海石油地质研讨会,2004.
[15] LI Ting-dong, MO Jie. Tectonic framwork of the west Circum-Pacific tectonic tract and the geological evoution of the East China Sea[J]. Marine Geology &Quaternary Geology,2002,22(4):1-6.
李廷栋,莫杰.中国滨太平洋构造域构造格架和东海地质演化[J].海洋地质与第四纪地质,2002,22(4):1-6.
[16] FENG Xiao-jie, CAI Dong-sheng, WANG Chun-xiu, et al. The meso-cenozoic tectonic evolution in East China Sea Shelf Basin[J]. China Offshore Oil and Gas(Geology),2003,17(1):33-37.
冯晓杰,蔡东升,王春修,等.东海陆架盆地中新生代构造演化特征[J].中国海上油气(地质),2003,17(1):33-37.
[17] LIU Jin-shui, LIAO Zong-ting, JIA Jian-yi, et al. The geological structure and tectonic evolution of the East China Sea Shelf Basin[J]. Shanghai Geology,2003(3):1-6.
刘金水,廖宗廷,贾健谊,等.东海陆架盆地地质结构及构造演化[J].上海地质,2003(3):1-6.
[18] Zheng Qiu-gen, ZHOU Zu-yi, CAI Li-guo, et al. Meso-Cenozoic tectonic setting and evolution of East China Sea shelf basin[J]. Oil & Gas Geology,2005,26(2):197-201.
郑求根,周祖翼,蔡立国,等.东海陆架盆地中新生代构造背景及演化[J].石油与天然气地质,2005,26(2):197-201.
[19] MURAUCHI S, DEN N, ASANO S, et al. Crustal Structure of the Philippine Sea[J]. J. Geophys Res,1968,73(10):3 143-3 171.
[20] HIRATA N, KINOSHITA H, KATAO H, et al. Report on DELP 1988 Cruise in the southern Okinawa Trough, Part III : Crustal structure of the southern Okinawa Trough[J]. Bull ERI Univ Tokyo,1991,66(1):37-70.
[21] LUAN Xi-wu,GAO De-zhang,YU Pu-zhi, et al. The crust velocity structure of a profile in the area of East China Sea and its vicinity[J]. Progress in Geophysics,2001,16(2):28-34.
栾锡武,高德章,喻普之,等.中国东海及邻近海域一条剖面的地壳速度结构研究[J].地球物理学进展,2001,16(2):28-34.
[22] GAO De-zhang, ZHAO Jin-hai, BO Yu-ling, et al. A profile study of gravitative-magnetic and seismic comprehensive survey in the East China Sea[J]. Chinese J. Geophys,2004,47(5):853-861.
高德章,赵金海,薄玉玲,等.东海重磁地震综合探测剖面研究[J].地球物理学报,2004,47(5):853-861.
[23] KLINGELHOEFER F, LEE C S, LIN J Y, et al. Structure of the southernmost Okinawa Trough from reflection and wide-angle seismic data[J]. Tectonophysics,2009,466(3-4):281-288.
[24] WANG T K, LIN S F, LIU C S, et al. Crustal structure of the southernmost Ryukyu subduction zone: OBS, MCS and gravity modelling[J]. Geophysical Journal International,2004,157(1):147-163.
[25] MCINTOSH K, NAKAMURA Y, WANG T K, et al. Crustal-scale seismic profiles across Taiwan and the western Philippine Sea[J]. Tectonophysics,2005,401(1-2):23-54.
[26] AI Y S, CHEN Q F, ZENG F, et al. The crust and upper mantle structure beneath southeastern China[J]. Earth and Planetary Science Letters,2007,260(3-4):549-563.
[27] PARKER R L. The rapid calculation of potential anomalies[J]. Geophysical Journal of the Royal Astronomical Society,1973,31(4):447-455.
[28] MCKENZIE D. Some remarks on the development of sedimentary basins[J]. Earth and Planetary Science Letters,1978,40(1):25-32.
[29] ZHANG Yun-fan, SUN Zhen, ZHOU Di, et al. The characteristics of cenozoic crustal thinning and its dynamic significance at northern continental margin of the South China Sea[J]. Science China,2007,37(12):1 609-1 616.
张云帆,孙珍,周蒂,等.南海北部陆缘新生代地壳减薄特征及其动力学意义[J].中国科学D辑,2007,37(12):1 609-1 616.
[30] ZHANG Hui-fang. Explaination for data of DSS profiles at Quan-Shan area in the coast of southeast China[J]. Earthquake Research in China,1988,4(2):96-105.
章惠芳.中国东南沿海地区泉汕爆破深地震测深资料的再解释[J].中国地震,1988,4(2):96-105.
[31] XIONG Shao-bai, LIU Hong. Crust Mantle Structure of Zhejiang Anhui Region and the Boundary between Yangzi Block and Huanan Block[J]. Progress in Geophysics,2000,15(4):3-17.
熊绍柏,刘宏兵.浙皖地区地壳—上地幔结构和华南与扬子块体边界[J].地球物理学进展,2000,15(4):3-17.
[32] YAO Bao-hua, ZHANG Zhen-quan, WANG Jia-lin, et al. Prospecting and research on fine crustal structure by using multi-geophysics survey methods in Shanghai region[J]. Chinese J. Geophys,2007,50(2):482-491.
姚保华,章振铨,王家林,等.上海地区地壳精细结构的综合地球物理探测研究[J].地球物理学报,2007,50(2):482-491.
[33] HAO Chong-tao YE Hong. The Cenozoic rate of crustal stretching of the East China Sea Shelf Basin[J]. Scientia Geologica Sinica,1999,34(1):29-39.
郝重涛,叶洪.东海陆架盆地新生代扩张率的估算[J].地质科学,1999,34(1):29-39.
[34] LIANG Rui-cai, WANG Shu-gong, WU Jin-Long. Preliminary study on geophysical field and the new crust in the middle of the Okinawa Trough[J]. Marine Geology &Quaternary Geology,2001,21(1):57-64.
梁瑞才,王述功,吴金龙.冲绳海槽中段地球物理场及对其新生洋壳的认识[J].海洋地质与第四纪地质,2001,21(1):57-64.
[35] LETOUZEY J, KIMURA M. The Okinawa Trough: Genesis of a back-arc basin developing along a continental margin[J]. Tectonophysics,1986,125(1-3):209-230.
[36] MASAAKI K. Back-arc rifting in the Okinawa Trough[J]. Marine and Petroleum Geology,1985,2(3):222-240.
[37] ZHOU Zu-yi, LIAO Zong-ting, JIN Xing-chun, et al. Okinawa Trough:The highest stage of continental tension rifting in backarc setting[J]. Marine Geology &Quaternary Geology,2001,21(1):51-55.
周祖翼,廖宗廷,金性春,等.冲绳海槽—弧后背景下大陆张裂的最高阶段[J].海洋地质与第四纪地质,2001,21(1):51-55.
[38] WU You-lin, LIN Ge, FAN Wei-ming, et al. Exploration on the formation and evolution back-arc basins-example of continental margins in East Asia[J]. Marine Geology &Quaternary Geology,1996,16(4):63-69.
吴有林,林舸,范蔚茗,等.弧后盆地的形成与演化探讨——以东亚陆缘区为例[J].海洋地质与第四纪地质,1996,16(4):63-69.
[39] JIN Xiang-long, YU Pu-zhi, LIN Mei-hua, et al. Preliminary study on the characteristics of crustal structure in the Okinawa Trough[J]. Oceanologia et Limnologia Sinica,1983,14(2):105-116.
金翔龙,喻普之,林美华,等.冲绳海槽地壳结构性质的初步探讨[J].海洋与湖沼,1983,14(2):105-116.
[40] JIN Xiang-long, ZHUANG Jie-zao, TANG Bao-jue, et al. The structural features of Okinawa Trough by seismic reflection[J]. Oceanologia et Limnologia Sinica,1985,16(6):481-489.
金翔龙,庄杰枣,唐宝珏,等.冲绳海槽反射地震的结构特征[J].海洋与湖沼,1985,16(6):481-489.
[41] HAO Tian-yao, LIU Jian-hua, Guo Feng, et al. Research on crustal structure and lithosphere property in the Okinawa area[J]. Chinese J. Geophys,2004,47(3):462-468.
郝天珧,刘建华,郭锋,等.冲绳海槽地区地壳结构与岩石层性质研究[J].地球物理学报,2004,47(3):462-468.
[42] GAO Jin-yao, ZHANG Tao, FANG Yin-xia, et al. Faulting,magmatism and crustal oceanization of the Okinawa Trough[J]. Acta Oceanologica Sinica,2008,30(5):62-70.
高金耀,张涛,方银霞,等.冲绳海槽断裂、岩浆构造活动和洋壳化进程[J].海洋学报(中文版),2008,30(5):62-70.