258 structure and material, but also deduce the geodynamic events occurred in the geological time. The middle and lower reaches of Yangtze River metal

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1 May : Acta Geoscientica Sinica Vol.32 No.3: www. 地球学报.com 摘 SinoProbe-03 年度进展综述 1), 1), 2), 3), 4), SinoProbe-03-CJ 1), ; 2), ; 3), ; 4), 要 :,,,,, 2010 SinoProbe km, km MT,,,,, Moho,,,,,, (adakite) (shoshonite) 关键词 : ; ; ; ; ; ; 中图分类号 : P542.1; P61 文献标志码 : A doi: /cagsb Probing on Deep Structure of Middle and Lower Reaches of the Yangtze Metallogenic Belt and Typical Ore Concentration Area: A Review of Annual Progress of SinoProbe-03 LÜ Qing-tian 1), SHI Da-nian 1), TANG Jing-tian 2), WU Ming-an 3), CHANG Yin-fo 4), SinoProbe-03-CJ Team 1) MLR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing ; 2) School of Geosciences and Info-physics, Central South University, Changsha, Hunan ; 3) Geological Survey of Anhui Province, Hefei, Anhui ; 4) Department of land and Resources of Anhui Provinces, Hefei, Anhui Abstract: The present crustal structure and composition are "products" of complex geodynamic processes through geological time, which maintains the relics and fabrics formed during the major geological movement. The image of the products based on modern geophysical technology can help not only comprehend the current state of the ( : SinoProbe-03) ( : ) 2010 : ; : : :,, 1964, lqt@cags.ac.cn SinoProbe-03-CJ :,,,,,,,,,,,,,,,

2 258 structure and material, but also deduce the geodynamic events occurred in the geological time. The middle and lower reaches of Yangtze River metallogenic belt is an important iron, copper and polymetallic base in China, whose deep dynamic processes have constituted the debate focus among researchers. In 2010, a broadband seismic detection about 300km long has been performed in this belt by SinoProbe-03 project, and five seismic reflection, MT and geochemical profiles totally 250km long have been completed over Lujiang-Zongyang ore concentration area. A couple of significant discoveries were made on the basis of preliminary processing and analysis, such as the existence of low-velocity bodies in the upper mantle of the metallogenic belt, short-distance variations of upper mantle anisotropy, local Moho uplift, blur interface between lithosphere and asthenosphere, double-layer crustal structure with thicker upper crust than lower crust. The reflection pattern of crust indicates that it has experienced early compression and later extensional deformation. These discoveries support the dynamic model of asthenosphere uplift, lithospheric thinning, melting of enriched mantle and lower crust thickening and delamination. With these discovers, the extensive development of Cretaceous adakite, shoshonite in metallogenic belt and the causes for the formation of the giant Yangtze River metallogenic belt can also be explained. Key words: Broadband Seismics; Reflection Seismics; Magnetotelluric; Tomography; Anisotropy; Receiver function; Crustal structure Cu Fe Au S, 7 200, ( 1), (Pan et al., 1999),,, (SinoProbe-03), km, 5 MT (, 2011),, ,, 2010,,,,,,,, 1 区域构造地质背景 ( ) - (UHP) -, -, (, 1991),,, : ( )- ( 图 1 长江中下游成矿带主要矿集区矿床分布及地震剖面位置示意图 ( 据 Pan et al., 1999; 周涛发, 2008 改绘 ) Fig. 1 Sketch map showing the distribution of major ore Concentration areas, deposits and the location of seismic profiles over the middle and lower reaches of the Yangtze River (after Pan et al., 1999; ZHOU Tao-fa, 2008) MT The blue triangles denote the locations of broadband station, Blue lines indicate the locations of seismic reflection, MT and borehole geochemical profiles over Luzong ore Concentration area

3 : Ma) -, - ( ), (Li, 1998),,, -,, - ;, Lapierre (1997) - -,,,,,,,,, NE,, ; Zhou and (, 1991), Li(2000) Ma,,,, 1000 km - -, -,, -, ; Li -, (2007) (roll-back), (, 1991;, 2008),,,, (, 2001) (, 1986),,,, -,,, (, 2004),, ( - ) Ma,, ( ) (, 1997) (, 2001, 2003; Xu et al., 2002),,, (, 2004),,, -,,, (, 2007) 2 数据采集与处理 2.1 (, 2011),,,,, 300 km : ( ) (TLF) (CHF) ( ) (MSF) ( 2) MT , 46, Guralp 3ESPCD, 5 km, 250 km , 3, 60, 600 GB, 253

4 260 图 2 长江中下游成矿带宽频地震剖面位置及周边地质构造图 Fig. 2 The tectonic map of the middle and lower reaches of the Yangtze River with the locations of broadband stations TLF- ; CHF- ; MSF- ; JNF- ; NCB- ; YZB- TLF-Tanlu fault; CHF-Chuhe fault; MSF-Maoshan fault; JNF-Jiangnan fault; NCB-North China Block; YZB-Yangtze Block, 300 km (410 km ), P (Jiang et al., 2010; Shi et al., 2010;, 2011) :,, 410 km (Shi et al., 2010;, 2011) : SKS SKKS,,, (Shi et al., 2010;, 2011) :, (Jiang et al., 2010) 2.2 5, - 3 (Lz-1 Lz-2 Lz-3), ; - 2 (Lz-4 Lz-5), ( 3) - ; -,, km SN428XL, (m), 720, 80 m, 20 m, 90;, : m, 16 m, 4 6 kg, 6 kg ; m, 18 m 8 10 kg,

5 : 261 图 3 庐枞矿集区周边地质及反射地震 MT 剖面位置示意图 Fig. 3 Geological map of the Lujiang-Zongyang ore concentration area with the locations of seismic reflection and MT profiles Lz-1 Lz-5, 7, 8 Lz-1 and Lz-5 denote the number of the seismic reflection profiles; The yellow round dots and red numbers correspond with abscissa in the Fig.7; the red crosses and black numbers correspond with abscissa in the Fig kg; 20DX-10, 12, 12 s, 2 ms LZ-2, 1S2R ( ), 40 m, 10 m, CGG OMEGA Promax, :, : (1),, ; (2),, ; (3), ; (4), ; (5),, :

6 262 ; T-X,, ;, ; (6), ; (7),,,, ; (8) DMO, DMO, ; (9),,, MT 5, 523, V5-2000( MTC-50, Hz), 1 V8, 500 m, 24 6 图 4 庐枞矿集区反射地震处理流程图 Fig. 4 The seismic data processing flow chart of Lujiang-Zongyang ore concentration area,,, 6, (, 2011) (DZ/T ), MT, 354, 71.6%, 119, 23.8% MT,,,,,,,, 5 MT,, 5 (, 2011), 3579,,,, As Sb Hg W Mo Cu Pb Zn Ag Au 10 3 初步结果及其动力学与找矿勘查的意义 3.1 (Jiang et al., 2010) :,, (7 80 km±)p, (CHF) (JNF),, km ( ),,,, 150 km ; km,,, km, ( 5), (Shi et al., 2010;, 2011) : Moho, 3 5 km; (7 80 km±),,

7 : 263 Fig. 5 图 5 长江中下游成矿带远震层析成像初步结果 Preliminary results of teleseismic tomography crossing over the middle and lower reaches of Yangtze River A- ; B- ; C- ; D- P A-Distribution of teleseismic events used in tomography, red triangle represents the center of stations; B-Location of broadband stations and teleseismic profiles; C-Horizontal slices of the tomography with different depth; D-Vertical cross sections of P-wave velocity images ; 410 km,,, ( ) (Shi et al., 2010) ( 6), E SE ( ) NE, ; W NW, NW NNW,, ; (Helffrich et al., 1994),, :, (, 2001, 2003; Wang et al., 2006) (Kula Izanagi ) (Li et al, 2007),,,, 3.2 5,

8 264 Lz-2 Lz-4 ( 7), 30 km, Moho 35 km, 30 km NE-SW (Lz-4 ), Moho,, km, km (6 s TWT),,, (Lu et al., 2010),,,,,,,, ( 7a)CDP ),,,, Moho,, (, ), Lz-3 Lz-4, 9 12 km,, (Basin and Range) (Allmendinger et al., 1983),,, 30 km ;, km ;, ;,,, 图 6 长江中下游地震各向异性计算初步结果 (a, 红线 : E SE 方向地震各向异性快波偏振方向和快慢波时差 ; 黄线 : W NW 方向地震各向异性快波偏振方向和快慢波时差 ) 和长江中下游地震接收函数成像初步结果 (b) Fig. 6 Preliminary results of seismic anisotropy crossing over the middle and lower reaches of Yangtze River(a, Red lines: fast wave directions and time delay between fast and slow waves using events coming from E and SE direction; Yellow lines: fast wave direction and time delay between fast and slow waves using events coming from W and NW direction) and preliminary results of Stacked receiver function image crossing over the middle and lower reaches of Yangtze River(b) 2, ( - ),, ( ),, (, 2001, 2003; Wang et al., 2006),, 50 km, ( ),

9 : 265 图 7 庐枞矿集区 Lz-2 Lz-4 反射地震偏移剖面线条图 Fig. 7 Line drawings of migrated section of Lz-2 and Lz-4 profiles over Lujiang-Zongyang ore concentration area (Kay et al, 1993) 3.3 MT MT Geo_GMES, (, 1997), MT ;,, (, 2011) Lz-2 Lz-4 (Katsube et al., 1994): Ω.m,,,,, ( Ω.m) 8, ( ),,, 300 Ω.m, (thrusting),, 5 6 km;, 1.0 km, 800 Ω.m 800 m,, MT, -,, Lz-4, ;

10 266,, ( 9), Lz-1 Cu Zn Pb Ag, As Hg, 3.5 km,, Lz km Cu Zn Pb,,, ; Lz-2 Cu, Ag, Lz-4 ( 3 9) Cu Pb Zn Ag Hg,, Cu Pb Zn Ag ; Ag Cu Pb Zn, Pb Zn Ag,, 4 讨论与结论, SinoProbe km, km, 5 MT 500, : 1) Fig. 8 图 8 庐枞矿集区 Lz-2 Lz-4 大地电磁测深二维反演结果 2D magnetotelluric sounding inversion results of Lz-2 and Lz-4 profiles over Lujiang-Zongyang ore concentration area Fig. 9 图 9 反射地震钻孔地球化学测量剖面, 显示沿剖面成矿元素的变化 The seismic drill-hole geochemical profiles showing ore-elements variations along the profiles

11 : 267,,,, Moho ; 2) 30 km, Moho 3 5 km ;,,,, ( - ), ( ),,,,,, 50 km, ( ), ; 3) 3D 800 m,, 致谢 : 感谢中石化西南石油局云南物探公司在极其艰苦的条件下, 完成了庐枞矿集区高质量的反射地震数据感谢专项负责人董树文研究员李廷栋院士, 项目专家委员会陈毓川滕吉文院士, 黄宗理肖庆辉柴育成邓军王瑞江王椿庸研究员等对项目的一贯支持和鼓励感谢财政部国土资源部和国家自然科学基金委对项目的资助参考文献 :,, [M]. : : , MT [J]., 32(3): ,,,,,,, [J]., 81(11): [J]., 12(2): ,, SinoProbe SinoProbe- 03 [J]., 32(S1): ,,, [J]. (D ), 34(9): ,,,, [J]., 18(2): ,,,,,, MASH [J].,.,,,,,, [M]. : : ,,, : adakite [J]., 30(4): ,,,, [J]. (D ), 33(4): ,,, [J].,.,,,,,, [J]., 17: ,, [J]., 24(8): References: ALLMENDINGER R W, SHARP J W, TISH D V, SERPA L, BROWN L, KAUFMN S, OLIVER J, SMITH R B Cenozoic and Mesozoic structure of the eastern Basin and Range province, Utah, from COCORP seismic-reflection data[j]. Geology, 11: CHANG Yin-fo, LIU Xiang-pei, WU Yan-chang The Copper-iron belt of the middle-lower reaches of the Changjiang River[M]. Beijing: Geological Publishing House: 1-379(in Chinese). DAI Shi-kun, XU Shi-zhe Rapid inversion of magnetotelluric data for 2-D and 3-D continuous media[j]. Oil Geophysical Prospecting, 32(3): (in Chinese with English abstract). DONG Shu-wen, ZHANG Yue-qiao, YANG Zhen-yu, JI Qiang, WANG Tao, HU Jian-min, CHEN Xuan-hua Jurassic Tectonic Revolution in China and New Interpretation of the Yanshan Movement[J]. Acta Geologica Sinica, 81(11): (in Chinese with English abstract). DONG Shu-wen Tectonic Analysis on Genesis of Metallogenetic Belt of Middle-lower Yangtze River[J]. Acta Geoscientica Sinica,12(2):43-56(in Chinese with English abstract). HELFFRICH G, SILVER P, GIVEN H Shear-wave splitting variation over short spatial scales on continents[j]. Geophys. J. Int., 119: JIANG G, ZHANG G, LU Q, SHI D Teleseismic tomography

12 268 beneath the mid-lower Yangtze region in China[C]. Abstract T23B-2248, presented at 2010 Fall Meeting, AGU, San Francisco, Calif., Dec. KATSUBE T J, SALISBURY M Implications of laboratory electrical measurements on interpretation of EM-surveys and origin of the Sudbury structure[j]. Geophysical Research Letters, 21(10): KAY R W, KAY S M Delamination and Delamination magmatism[j]. Tectonophysics, 219: LAPIERRE H, JAHN B M, CHARVET J, YU Y W Mesozoic felsic arc magmatism and continental olivine tholeiite in Zhejiang Province and their relationship with the tectonic activity in southeastern China[J]. Tectonophysics, 274: LI Z X, LI X H Formation of the 1300-km-wide intracontinental orogen and postorogenic magmatic province in Mesozoic South China: a flat-slab subduction model[j]. Geology, 35(2): LI Z X Tectonic history of the major East Asia lithospheric blocks since the mid-proterozoic a synthesis. In Mantle Dynamic and Plate Interaction in East Asia[M]. Geodynamics 27, the Americian Geophysical Union: structure and three-dimension deep exploration for mineral resources: An introduction to SinoProbe-03 project[j]. Acta Geoscientica Sinica, 32(s1): 49-64(in Chinese with English abstract). LÜ Qing-tian, HOU Zeng-qian, YANG Zhu-sen, SHI Da-nian The underplating and dynamic evolution model of the mid-lower Yangtze region- constraints from geophysical data[j]. Science in China, Ser. D, 34(9): (in Chinese with English abstract). MAO Jian-ren, TAO Kui-yuan, YANG Zhu-liang, ZHU Yun-he, XUE Huai-min Mesozoic intracontinental magmatism geodynamics background Southeast China[J]. Volcanology & Mineral Resources, 18(2): (in Chinese with English abstract). PAN Y M, DONG P The Lower Changjiang (Yangzi / Yangtze River)metallogenic belt, east central China: intrusion- and wall rock-hosted Cu-Fe-Au, Mo, Zn, Pb, Ag deposits[j]. Ore Geology Reviews, 15: SHI D, LÜ Q, YAN J, XU W, ZHANG G, JIANG G, DONG S Crutal and upper mantle structure beneath the mid-lower Yangtze metallogenic belt revealed by passive-source seismic array[c]. Abstract T11F-07, presented at 2010 Fall Meeting, AGU, San Francisco, Calif., Dec. SHI Da-nian, LÜ Qing-tian, XU Wen-yi, YAN Jia-yong, ZHAO Jin-hua, Dong Shu-wen, CHANG Yin-fo Crustal structures beneath the mid-lower Yangtze Metallogenic belt and its adjacent regions in Eastern China- Evidences from P-wave receiver function imaging for a MASH metallizaion process[j]. Acta Geologica Sinica, in press(in Chinese with English abstract). TANG Yong-Cheng, WU Yan-Chang, CHU Guo-zheng, XING Feng-ming, WANG Yong-min, CAO Fen-yang, CHANG Yin-fo Geology of Copper-Gold polymetallic deposits in the along-changjiang Area of Anhui province[m]. Beijing: Geological Pulishing House(in Chinese). WANG Q, WYMAN D A, XU J F, ZHAO Z H, JIAN P, XIONG X L, BAO Z W, LI C F, BAI Z H Petrogenesis of cretaceous adakitic and shoshonitic igneous rocks in the Luzong area, Anhui Province (eastern China): Implications for geodynamics and Cu-Au mineralization[j]. Lithos, 89: WANG Qiang, ZHAO Zhen-hua, XIONG Xiao-lin, XU Ji-feng Melting of the underplated basaltic lower crust:evidence from the Shaxi adakitic sodic quartz diorite-porphyrites,anhui Province,China[J]. Geochinica, 30(4): (in Chinese LU Q, DONG S, WU M, SHI D, YAN J, CHANG Y Crustal with English abstract). structure of volcanic terrane in the extensional tectonics, WANG Qiang, ZHAO Zhen-hua, XU Ji-feng, XIONG Xiao-lin, Eastern China, as revealed by seismic reflection profiling (Invited)[R]. abstract T11F-06, presented at 2010 Fall Meeting, in Yanshan period and their constraints to the deep dynamic BAO Zhi-wei The causes of formation intrusive rocks AGU, San Francisco, Calif Dec. process in Tongling area, Anhui Province[J]. Science in China, LÜ Qing-tian, CHANG Yin-fo, SinoProbe-03 team Crustal Ser.D, 33(4): (in Chinese with English abstract). XIAO Xiao, TANG Jing-tian, ZHOU Cong, LÜ Qing-tian Magnetotelluric sounding and preliminary study of electrical structure in Lujiang-Zongyang ore concentrated Area[J]. Acta Geologica Sinica, in press(in Chinese with English abstract). XU J F, SHINJO R, DEFANT M J, WANG Q, RAPP R P Origin of Mesozoic adakitic intrusive rocks in the Ningzhen area of east China: Partial melting of delaminated lower continental crust[j]. Geology, 30: ZHANG Qi, WANG Yan, QIAN Qing, YANG Jin-hui, WANG Yuan-Long; ZHAO Tai-ping, GUO Guang-jun The characteristics and tectonic-metallogenic significances of the adakites in Yanshan period from eastern China[J]. Acta Petrologica Sinica, 17: (in Chinese with English abstract). ZHOU Tao-fa, FAN Yu, YUAN Feng Progress on petrogensis and metallogeny study of the mineralization belt of the Middle and Lower Reaches of the Yangtze River area[j]. Acta Petrologica Sinica, 24(8): (in Chinese with English abstract). ZHOU X M, LI W X Origin of late Mesozoic igneous rocks in Southeastern China: implication for lithosphere subduction and underplating of mafic magma[j]. Tectonophysics, 326:

14 17.,., Fig. 1 Bougeur gravity map of research region 2 Fig. 2 Magnetic map of research region

14 17.,., Fig. 1 Bougeur gravity map of research region 2 Fig. 2 Magnetic map of research region 1 7 1 Vol. 17 No. 1 2002 3 (13 23) PROGRESS IN GEOPHYSICS March 2002 (,,100101) [ ],, 39.,,. [ ] ; ; [] P738 [] A [ ]100422903 (2002) 0120013211 0,,.,,, NE [1 ],.., ( NE, EW,NE ),.,.,,. 1 20 20 km ( 10