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摘要: 华南大陆历经长期复杂的构造演化,其浅部复杂而多样的构造形态与深部壳幔结构及其动力学机制有着密切联系,但当前的深部探测资料有限,深部构造并不明确。为了研究华南的深部岩石圈结构状态,布设了多条宽频长周期大地电磁联合探测剖面。通过对景德镇-温州剖面的数据处理,获得了该剖面的岩石圈电性结构模型。分析表明:华夏地块与扬子地块东部的江南造山带以江绍断裂为界;华夏地块整体呈现高阻特征,可能具有深部岩石圈背景的上虞-政和-大浦断裂将其分为华夏褶皱带与东南沿海岩浆岩带;扬子地块东部的江南造山带整体电阻率较低,结构更破碎,受到深部改造明显,岩石圈底界约为110 km;剖面发现3处低阻带通道,可能与软流圈上涌相关;江绍断裂呈喇叭状向深部张开,华夏地块与扬子地块的裂解拼合可能与断裂深部的高导体活动有关。华夏地块与扬子地块的接触状态呈现为双向汇聚,华夏地块在上地幔挤入扬子地块,深部接触边界可能越过江绍断裂带。Abstract: The South China block has experienced a long and complicated tectonic evolution history which formed the present tectonic features. The surface tectonic structure is complex and diverse which has an inevitable contact with the deep structure. However, the detection of deep structure is limited and current deep state remain undefined. To investigate the deep lithospheric structure of the South China region, we have completed a series of joint detection profiles of broad band magnetotelluric(MT)and long period MT under the auspices of SinoProbe-02 project. The profile introduced is Jingdezhen-Wenzhou profile located in the northeast part of the South China region with a length of about 400 km. Based on the data analyses, the 2D inversions were conducted and the lithospheric electrical structure model was finally obtained. The inversion model reveals that:The profile mainly consists of the Cathaysia block and Jiangnan orogen which borders the East Yangtze block while the Jiangshao fault is the boundary fault of the two block. The Cathaysia block is generally resistive which is consistent with the strong magmatic activity and the stable Precambrian settings. It consists of two sub-tectonic unit, Cathaysia folded belt and the southeast coast magmatic belt. The Shangyu-Zhenghe-Dapu fault serving as the boundary fault may be a lithospheric fault. The structure of Jiangnan orogen seems more fractured and conductive which indicate that the Jiangnan orogen has experienced deep reconstruction. The lithosphere asthenosphere boundary(LAB)is detected in the northwest part of Jiangnan orogen with a depth of about 110 km. There are also three upwelling channel observed in the different location of the profile which are C1-C3 channel, C2-C3 channel and the relatively conductive zone between R4 and R5. These structures shows the reconstruction process from the deep. The trumpet shaped Jiangshao fault which is the coupling zone of Yangtze block and Cathaysia block opens to the deep and its characteristics reveals the deep agent of the former cracking-closure process. The coupling characteristcs turn to be a convergence structure and the Cathaysia block wedged into the Yangtze block in the upper mantle with the deep boundary went across the Jiangshao fault.
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Key words:
- Magnetotelluric /
- Electrical structure /
- Cathaysia block /
- Yangtze block /
- Jiangshao fault
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[1] 蔡军涛,陈小斌. 2010.大地电磁资料精细处理和二维反演解释技术研究(二)--反演数据极化模式选择.地球物理学报, 53(11):2703-2714.
[2] Cai Juntao and Chen Xiaobin. 2010. Refined techniques for data processing and two-dimensional inversion in magnetotelluric Ⅱ:Which data polarization mode should be used in 2D inversion. Chinese Journal of Geophysics, 53(11):2703-2714.
[3] 邓国辉,罗春林,楼法生等. 2002.德兴-黄山断裂带及其邻区的地质研究进展.资源调查与环境, 23(4):250-256.
[4] Deng Guohui, Luo Chunlin, Lou Fasheng et al. 2002. Recent developments in studying geology of Dexing-Huangshan fault zone and its adjacent areas. Resources Survey and Environment, 23(4):250-256.
[5] 邓国辉,刘春根,冯晔. 2005.赣东北-皖南元古代造山带构造格架及演化.地球学报, 26(1):9-16.
[6] Deng Guohui, Liu Chungen and Feng Ye. 2005. Tectonic features and evolution of the Proterozoic orogenic belt between northeastern Jiangxi and southern Anhui. Acta Geosicientia Sinica, 26(1):9-16.
[7] 邓前辉,刘国栋,刘金汉等. 1990.湖北襄樊-福建罗源的大地电磁测量与地壳上地幔电性特征研究.地震地质, 12(2):149-158.
[8] Deng Qianhui, Liu Guodong, Liu Jinhan et al. 1990. The observation of magnetotelluric and electrical characteristics of the crust-upper mantle along Hubei Xiangfan-Fujian Luoyuan profile. Seismology and Geology, 12(2):149-158.
[9] 董树文,李廷栋,陈宣华等. 2012.我国深部探测技术与实验研究进展综述.地球物理学报, 55(12):3884-3901.
[10] Dong Shuwen, Li Tingdong, Chen Xuanhua et al. 2012. Progress of deep exploration in mainland China:A review. Chinese Journal of Geophysics, 55(12):3884-3901.
[11] 韩江涛,刘国兴,韩凯. 2012.粤北地区乳源-潮州MT剖面深部电性结构及地学意义.吉林大学学报(地球科学版), 42(4):1186-1191.
[12] Han Jiangtao, Liu Guoxing and Han Kai. 2012. Electrical structure and geological significance of Ruyuan-Chaozhou magnetotelluric profile in northern Guangdong. Journal of Jilin University(Earth Science Edition), 42(4):1186-1191.
[13] 韩凯,刘国兴,韩江涛等. 2012.乐昌-霞葛MT剖面深部电性结构研究.地球物理学进展, 27(3):997-1007.
[14] Han Kai, Liu Guoxing, Han Jiangtao et al. 2012. The deep electrical structure of the Lechang-Xiage profile with MT method. Progress in Geophysics, 27(3):997-1007.
[15] 华仁民,李晓峰,陆建军等. 2000.德兴大型铜金矿集区构造环境和成矿流体研究进展.地球科学进展, 15(5):525-533.
[16] Hua Renmin, Li Xiaofeng, Lu Jianjun et al. 2000. Study on the tectonic setting and ore-forming fluids of Dexing large ore-concentrating area, Northeast Jiangxi Province. Advance in Earth Sciences, 15(5):525-533.
[17] 蒋洪堪,战双庆,王宏勋. 1992.四川大足-福建泉州深部地电特征.地球物理学报, 35(2):214-222.
[18] Jiang Hongkan, Zhan Shuangqing and Wang Hongxun. 1992. The deep geoelectrical characteristics in Dazu, Sichuan-Quanzhou, Fujian. Chinese Journal of Geophysics, 35(2):214-222.
[19] 金胜,张乐天,魏文博等. 2010.中国大陆深探测的大地电磁测深研究.地质学报, 84(6):808-817.
[20] Jin Sheng, Zhang Letian, Wei Wenbo et al. 2010. Magnetotelluric method for deep detection of Chinese continent. Acta Geologica Sinica, 84(6):808-817.
[21] 孔祥儒,刘士杰,张建军等. 1991.福建东部地区大地电磁测深研究.地球物理学报, 34(6):724-735.
[22] Kong Xiangru, Liu Shijie, Zhang Jiangjun et al. 1991. Magnetotelluric sounding studies in eastern area of Fujian Province. Chinese Journal of Geophysics, 34(6):724-735.
[23] 刘国兴,韩凯,韩江涛. 2012.华南东南沿海地区岩石圈电性结构.吉林大学学报(地球科学版), 42(2):536-544.
[24] Liu Guoxing, Han Kai and Han Jiangtao. 2012. Lithosphere electrical structure in southeast coastal region, South China. Journal of Jinlin University(Earth Science Edition), 42(2):536-544.
[25] 刘营,徐义贤,张胜业等. 2013.华南地区岩石圈电性特征及其地球动力学意义.地球物理学报, 56(12):4234-4244.
[26] Liu Ying, Xu Yixian, Zhang Shengye et al. 2013. Lithospheric electrical characteristics in South China and its geodynamic implication. Chinese Journal of Geophysics, 56(12):4234-4244.
[27] 毛景文,张建东,郭春丽. 2010.斑岩铜矿-浅成低温热液银铅锌-远接触带热液金矿矿床模型:一个新的矿床模型--以德兴地区为例.地球科学与环境学报, 32(1):1-14.
[28] Mao Jingwen, Zhang Jiandong and Guo Chunli. 2010. Porphyry Cu, epithermal Ag-Pb-Zn, distal hydrothermal Au deposits:A new model of mineral deposit:Taking the Dexing area as an example. Journal of Earth Sciences and Environment, 32(1):1-14.
[29] 芮宗瑶,张立生,陈振宇等. 2004.斑岩铜矿的源岩或源区探讨.岩石学报, 20(2):229-238.
[30] Rui Zongyao, Zhang Lisheng, Chen Zhenyu et al. 2004. Approach on source rock or source region of porphyry copper deposits. Acta Petrologica Sinica, 20(2):229-238.
[31] 单春玲. 2010.华南地区桂东-厦门MT剖面电性结构研究(硕士学位论文).长春:吉林大学. 1-61.
[32] Shan Chunling. 2010. Study of Electric Structure of Guidong-Xiamen Profile in South China with MT Method(Master's Thesis). Changchun:Jilin University. 1-61.
[33] 石应骏,王礼棠,杨明高. 1989.福建地区深部电性分布的某些特征.成都理工大学学报(自然科学版), 16(1):117-123.
[34] Shi Yingjun, Wang Litang and Yang Minggao. 1989. Distribution of subsurface electrical properties in Fujian Province. Journal of Chengdu University of Technology(Science & Technology Edition), 16(1):117-123.
[35] 舒良树,周新民. 2002.中国东南部晚中生代构造作用.地质论评, 48(3):249-260.
[36] Shu Liangshu and Zhou Xinmin. 2002. Late Mesozoic tectonism of Southeast China. Geological Review, 48(3):249-260.
[37] 舒良树. 2012.华南构造演化的基本特征.地质通报, 31(7):1035-1053.
[38] Shu Liangshu. 2012. An analysis of principal features of tectonic evolution in South China block. Geological Bulletin of China, 31(7):1035-1053.
[39] 孙洁,晋光文,江钊等. 2001.用大地电磁测深法研究华南地区岩浆活动及深部结构.地震地质, 23(2):328-329.
[40] Sun Jie, Jin Guangwen, Jiang Zhao et al. 2001. Magmatic activity and the deep structure of South China inferred from magnetotelluric sounding data. Seismology and Geology, 23(2):328-329.
[41] 熊绍柏,刘宏兵. 2000.浙皖地区地壳-上地幔结构和华南与扬子块体边界.地球物理学进展, 15(4):3-17.
[42] Xiong Shaobai and Liu Hongbing. 2000. Crust-mantle structure of Zhejiang-Anhui region and the boundary between Yangzi block and Huanan block. Progress in Geophysics, 15(4):3-17.
[43] 熊小松,高锐,李秋生等. 2009.深地震探测揭示的华南地区莫霍面深度.地球学报, 30(6):774-786.
[44] Xiong Xiaosong, Gao Rui, Li Qiusheng et al. 2009. The Moho depth of South China revealed by seismic probing. Acta Geoscientica Sinica, 30(6):774-786.
[45] 徐鸣洁,舒良树. 2001.中国东南部晚中生代岩浆作用的深部条件制约.高校地质学报, 7(1):21-33.
[46] Xu Mingjie and Shu Liangshu. 2001. Deep geological conditions constraning the Late Mesozoic magmatism in SE China. Geological Journal of China Universities, 7(1):21-33.
[47] 徐先兵,汤帅,李源等. 2015.江南造山带东段新元古代至早中生代多期造山作用特征.中国地质, 42(1):33-50.
[48] Xu Xianbing, Tang Shuai, Li Yuan et al. 2015. Characteristics of Neoproterozoic-Early Mesozoic multiphase orogenic activities of eastern Jiangnan orogen. Geology in China, 42(1):33-50.
[49] 杨明桂,黄水保,楼法生等. 2009.中国东南陆区岩石圈结构与大规模成矿作用.中国地质, 36(3):528-543.
[50] Yang Minggui, Huang Shuibao, Lou Fasheng et al. 2009. Lithospheric structure and large-scale metallogenic process in Southeast China continental area. Geology in China, 36(3):528-543.
[51] 张国伟,张本仁,袁学诚等. 2001.秦岭造山带与大陆动力学.北京:科学出版社. 1-855.
[52] Zhang Guowei, Zhang Benren, Yuan Xuecheng et al. 2001. Qiling Orogenic Belt and Continental Dynamics. Beijing:Science Press. 1-885.
[53] 张国伟,郭安林,姚安平. 2006.关于中国大陆地质与大陆构造基础研究的思考.自然科学进展, 16(10):1210-1215.
[54] Zhang Guowei, Guo Anlin and Yao Anping. 2006. Thought on the geology and continental tectonics of China progress. Progress in Natural Science, 16(10):1210-1215.
[55] 张国伟,郭安林,董云鹏等. 2011.大陆地质与大陆构造和大陆动力学.地学前缘, 18(3):1-12.
[56] Zhang Guowei, Guo Anlin, Dong Yunpeng et al. 2011. Continental geology, tectonics and dynamics. Earth Science Frontiers, 18(3):1-12.
[57] 张国伟,郭安林,王岳军等. 2013.中国华南大陆构造与问题.中国科学:地球科学, 43(10):1553-1582.
[58] Zhang Guowei, Guo Anlin, Wang Yuejun et al. 2013. Tectonics of South China continent and its implications. Science China Earth Science, 56(11):1804-1828.
[59] Groom R W and Bailey R C. 1989. Decomposition of magnetotelluric impedance tensors in the presence of local three-dimensional galvanic distortion. Journal of Geophysical Research, 94(B2):1913-1925.
[60] Hansen P C. 1992. Analysis of discrete ill-posed problems by means of the L-curve. SIAM Review, 34(4):561-580.
[61] Hansen P C and O'Leary D P. 1993. The use of the L-curve in the regularization of discrete ill-posed problems. SIAM Journal on Scientific Computing, 14(6):1487-1503.
[62] Rodi W and Mackie R L. 2001. Nonlinear conjugate gradients algorithm for 2-D magnetotelluric inversion. Geophysics, 66(1):174-187.
[63] Wang X B, Zhang G, Fang H et al. 2014. Crust and upper mantle resistivity structure at middle section of Longmenshan, eastern Tibetan Plateau. Tectonophysics, 619-620:143-148.
[64] Zhang L T, Jin S, Wei W B et al. 2015. Lithospheric electrical structure of South China imaged by magnetotelluric data and its tectonic implications. Journal of Asian Earth Sciences, 98:178-187.
[65] Zhao G Z, Unsworth M J, Zhan Y et al. 2012. Crustal structure and rheology of the Longmenshan and Wenchuan Mw 7.9 earthquake epicentral area from magnetotelluric data. Geology, 40(12):1139-1142.
[66] Zhou X M and Li W X. 2000. Origin of Late Mesozoic igneous rocks in southeastern China:Implications for lithosphere subduction and underplating of mafic magmas. Tectonophysics, 326(3-4):269-287.
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