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Science China Earth Sciences 2005年第8期48卷 1089-1105页

作者： FAN Qicheng1.2. ZHANG Hongfu1. SUI Jianli1. ZHAI Mingguo1. SUN Qian2.& LI Ni2.1. institute of {1. and Geophysics, Chinese Academy of Sciences, Beijing 1.002., China {2., China seismological bureau, Beijing 1.002., China 1. institute of {1. and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of geology China Seismological Bureau 100029 Beijing China

On the basis of mineral assemblage, mineralogy, petrology, and major, trace ele-mental and isotopic geochemistry of the underplated granulite- and eclogite-facies accumulate, peridotite and pyroxenite xenoliths entrained in Hannuoba Cenozoic basalts, this work con-strained the petrological constituents for the crust-mantle transitional zone, which is supported by the results of high-temperature and pressure velocity experiments on rocks and geophysics deep survey. Present lower part of lower crust is mainly composed of granulite-facies mafic accumu-lates (dominantly plagioclase websterite) and crust-mantle transitional zone dominantly com-posed of eclogite-facies pyroxenites with or without garnet and spinel lherzolites; Archaean ter-rain granulite is only nominally early lower crust. Magma underplating in the crust-mantle boundary led to the crustal vertical accretion and the formation of the crust-mantle transitional zone, which is a significant mechanism for the chemical adjustment of the crust-mantle boundary since the Phanerozoic.

关键词： magma underplating, xenolith petrology, geochemistry, cust-mantle boundary constituent, Hannuoba.

Si-and alkali-rich melt inclusions in minerals of mantle peridotites from eastern China:Implication for lithospheric evolution

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Science China Earth Sciences 2006年第1期49卷 43-49页

作者： FAN Qicheng1. SUI Jianli2. XU Ping2. LI Ni1. SUN Qian1.& WANG Tuanhua1.1. institute of {1., China {2. bureau, Beijing 1.002., China 2. institute of geology and Geophysics, Chinese Academy of Sciences, Beijing 1.002., China 1. institute of {1. China Seismological Bureau Beijing 100029 China 2. institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Minerals of spinel- and garnet-facies mantle xenoliths entrained in Cenozoicbasalts from eastern China (North China, Northeastern China and Southeastern China coastal area)contains lots of melt inclusions. Studies on these melt inclusions show that the glass inclusionsare rich in SiO_2.(60%—68%) and alkalis (K_2.+Na_2. = 5%—1.%, especially for K_2.) as well asvolatiles such as H_2. and CO_2.(2.—7%), which belong to dacites and andesites of the high-K calcicalkali series rocks with few shoshonites. High Al and Ca diopside in melt inclusion is the productof melt crystallization at high temperature and pressure, rather than the product ofdevitrification. Results show that these K-rich (in general K_2. > 3%) intermediate-acidic silicatemelt inclusions have characteristics of continent without a genetical link to host basalts and theirphenocrystic minerals. Thus, these trapped melt inclusions represent melts of Mesozoic lithosphericmantle-crust interaction and imply that the continental lithospheric mantle beneath eastern Chinahad undergone fragmentation and recreation processes during the Mesozoic and Cenozoic periods. Thisresult undoubtly provides important implication for the evolution of sub-continental lithospherebeneath eastern China. We propose that these Si- and alkalis-rich melts should be responsible forthe mantle chemical heterogeneity underneath eastern China.

关键词： Si- and alkali-rich melt inclusion, mantle peridotite, lithospheric evolution, eastern China.

The history of crustal uplift and metamorphic evolution of Panzhihua-Xichang micro-palaeoland, SW China:Constraints on Sm-Nd, ^(40)Ar/^(39)Ar and FT ages of granulites

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Science China Earth Sciences 2004年第8期47卷 689-703页

作者： XU Shijin1. LIU Wenzhong1. WANG Rucheng1. YU Hangbo1. LI Daming2. WAN Jinglin2.& FANG Zhong1.1. Department of Earth Sciences and State Key Laboratory for Mineral Deposits Research, Nanjing University, Nanjing 2.0093, China 2. institute of geology, China {1. {2., Beijing 1.002., China 1. Department of Earth Sciences and State Key Laboratory for Mineral Deposits Research Nanjing University 210093 Nanjing China 2. institute of geology China Seismological Bureau 100029 Beijing China

Panzhihua-Xichang (Panxi) micro-palaeoland is the oldest terrane on the western margin of the Yangtze Block. Some intermediate-basic granulites are considered to be the crys-talline basement of lower crust in the terrane. Granulite-facies metamorphism of the granulites was developed in the period from 1.86 Ma to 1.2. Ma. The origin of granulites was related to the collision orogenic process occurring when the micro-palaeolands merged to form the Rodinia Supercontinent. Amphibolite-facies retrogressive metamorphism of granulites took place in the period from 877 Ma to 82. Ma. This period was consistent with the breakup time of the Rodinia Supercontinent. 40Ar/39Ar ages and fission track (FT) ages of granulites in the Panxi mi-cro-palaeoland show that the vertical movement history of crustal rocks was a slow uplift process of the rigid terrane in the time from Neoproterozoic to Mesozoic. The subduction of India Plate towards Euroasia Plate resulted in the rapid uplift of the Qinghai-Tibetan Block in Cenozoic. Meanwhile, the Qinghai-Tibetan Block moved towards east. Consequently the Panxi terrane was uplifted rapidly. As a result of the collision orogeny between the Qinghai-Tibetan Block and the Panxi terrane, the granulite-facies crystalline basement in this region was exhumed and exposed to the surface.

关键词： granulite,isotope geochronology,crustal uplift movement,Panzhihua-Xichang region,western margin of Yangtze Block.

Mantle-derived rare-gas releasing features at the Tianchi volcanic area, Changbaishan Mountains

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Chinese Science Bulletin 1997年第9期42卷 768-771页

作者： SHANGGUAN Zhiguan and SUN Mingliang1. institute of {1., State {2. bureau, Beijing 1.002., China 2. Lanzhou institute of {1., Chinese Academy of Sciences, Lanzhou 730000, China institute of {1. State Seismological Bureau Beijing China Lanzhou institute of {1. Chinese Academy of Sciences Lanzhou China

TIANCHI volcano,Changbaishan Mountains isthe largest modern active volcano in East *** times strong volcanic erupting activ-ities occurred in the Cenozoic *** vol-canic activities have revived again in the *** investi... 详细信息

关键词： Tianchi volcanic area Changbaishan Mountains mantle-derived rare gas 3He/ 4He 40 Ar/36 Ar 4He/2. Ne 4He/40Ar isotope ratios.

Crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science China Earth Sciences 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1. BAI Zhiming1. WANG Chunyong2. TENG Jiwen1. Lü Qingtian3, LI Jiliang1. SUN Shanxue1.& WANG Xinzheng1.1. {1. of {1. and Geophysics, Chinese Academy of Sciences, Beijing 1.002., China 2. {1. of Geophysics, Chinese seismological bureau, Beijing 1.0081. China 3. {1. of Deposition Resource, Chinese Academy of Geological Sciences, Beijing 1.0037, China 1. institute of {1. and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. {1. of Geophysics Chinese Seismological Bureau 100081 Beijing China 3. institute of Deposition Resource Chinese Academy of Geological Sciences 100037 Beijing China

The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the Yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 40 km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.

关键词： Gondwana blocks,Yangtze blocks,wide-angle profile,crustal structure,tectonic setting

Identification of Hercynian shoshonitic intrusive rocks in central Hainan Island and its geotectonic implications

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Science Bulletin 2006年第20期51卷 2507-2519页

作者： XIE Caifu1. 2. ZHU Jinchu1. DING Shijiang3, ZHANG Yeming2. FU Tai’an2.& LI Zhihong2.1. State Key Laboratory for Mineral Deposits Research and Department of Earth Sciences, Nanjing University, Nanjing 2.0093, China 2. Yichang institute of {1. and Mineral Resources, Yichang 443003, China 3. Hainan {2. of {1. and Mineral Resources, Haikou 5702.6, China Department of Otolaryngology University Hospital VU P.O. Box 7057 1007 MB Amsterdam The Netherlands State Key Laboratory for Mineral Deposits Research and Department of Earth Sciences Nanjing University Nanjing 210093 China

An identification has been made of some shoshonitic intrusive rocks in central Hainan Island recently. These rocks are K-rich (K2.=2.9%―5.1., K2./Na2.=0.95―2.1.0}, distinctly enriched in LILE and LREE, strongly depleted in Nb, Ta, and moder- ately depleted in Sr and Ti, with (87Sr/86Sr)i = 0.70859―0.71.2. and ε Nd(t) = (?2.77―?7.49). They were derived from an EMⅡ-type mantle source. The enrichment process is related to metasomatism of depleted mantle caused by a great amount of fluid-melt released from oceanic crust and terri- genous sediments at great depth (eclogite facies) during the subduction of the South China plate under the Indochina-South China Sea plate in the Carbon- iferous–Early Permian. A SHRIMP U-Pb zircon dating yields a crystallization age of 2.2.7 Ma for the sho- shonitic intrusions, which is coeval with the strongly peraluminous granites found in central Hainan Island. These two kinds of rocks generally possess syn-intrusion ductile deformation structures. Thus they are considered to have been generated during the early stage (syn-thrust phase) of a post-collisional event. The primary magma of shoshonitic rocks was produced at a depth > 80 km by decompression- dehydration melting of previously enriched litho- spheric mantle wedge, phlogopite-bearing garnet peridotite, which was in turn caused by the break-off of a descendent slab and upwelling of a hot as- thenosphere. The rising of melts was accompaniedby crustal contamination and crystallization fractiona- tion (AFC). Combining with other related data, it is proposed that the southwards subduction and amal- gamation of the South China plate with the Indo- China-South China Sea plate took place at ca. 2.7- 2.8 Ma, which was a part of the convergence proc- ess of the Pangea supercontinent. The suture zone was probably located along the line of Song Ma-Beibu Gulf-north margin of the Yunkai Moun- tains-Wuyi Mountains.

关键词： SHRIMP U-Pb dating Hercynian shoshonitic intrusive rocks post-collisional event enriched mantle Hainan Island.

Aoyitake plagiogranite in western Tarim Block, NW China: Age, geochemistry, petrogenesis and its tectonic implications

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Science China Earth Sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2. YU Haifeng3, YE Haimin2. ZHAO Yu2.& ZHANG Dongsheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2. Nanjing institute of {2. and Mineral Resources, Nanjing 2.0016, China 3. Tianjin institute of {2. and Mineral Resources, Tianjin 300170, China 4. The 2.d Regional Geological Investigation Party, Xinjiang bureau of {2. and Mineral Resources, Changji 831100, China 1. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 2. Nanjing {1. of {1. and Mineral Resources Nanjing 210016 China 3. Tianjin institute of {1. and Mineral Resources Tianjin 300170 China 4. The 2.d Regional Geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji 831100 China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW China. The plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2.and crystallized at 330.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. The granites are sodic with Na/K ratios (molar) between 4 and 87. Total REE (50-2.0 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3-0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2.M model ages of 470 to 580 Ma and positive εNd(331.Ma) values of 6.2. to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.

Experimental study of ore gabbro liquid immiscibility

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Science China Earth Sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1.2. XIA Bin1. ZHOU Yongsheng3 & JIN Zhenmin4 1. Guangzhou {1. of Geochemistry, Chinese Academy of Sciences, Guangzhou 51.640, China 2. Wuhan University, Wuhan 430072. China 3. {1. of {2., China seismological bureau, Beijing 1.002., China 4. Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China 1. Guangzhou institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Wuhan University 430072 Wuhan China 3. institute of {1. China Seismological Bureau 100029 Beijing China 4. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, China. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900— 1.0}0℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

Metallogenic geochemistry of Sb-mineralization in southern margin of North China platform

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Chinese Science Bulletin 1999年第S2期44卷 17-18页

作者： YANG Xiaoyong~1. YANG Xueming~1. ZHANG Jianjun~2. CAO Gaoshe~2.and ZHANG Zhengwei~2.1. Department of Earth and Space Sciences, University of Science and Technlogy of China, Hefei 2.002., China 2. institute of geology, Henan {1. of {2. and Mineral Resources, Zhengzhou 450053, China Department of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China institute of {1. Henan Bureau of Geology and Mineral Resources Zhengzhou 450053 China

1.Geological setting THE Sb mineralization zone in the south margin of North China platform is located in the transitional edgeof North China plate and Yangtze plate, belonging to Qinling fold system, whose tectonic line is inNWW-SEE direction regionally. Because of the huge compression caused by the collision of the twoplates, the rocks undergone strong deformation and metamorphism have very complicated structures. Theregional deep fault-Shuanghuaishu fault-controls Sb-mineralization zone belt, and all the Sb-oredeposits or mineralized spots appear alone at the very southern margin of the fault. The lithostragraphirunits in the mineralized zone are relatively simple, mainly composed of Jiebei Group （Pt2./sub>J2./sup>） of QinglingFormation （with middle-high metamorphsim） and the upper Triassic system （with little metamorphism）.

关键词： Sb-mineralization metallognic geochemistry North China plateform.

Fluid inclusion evidence for the involvement of organic matter in mineralization of Hg, Sb and Au deposits

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Chinese Science Bulletin 1999年第S2期44卷 197-199页

作者： SHI Jixi~1.and WANG Huayun~2.1. Open Laborator of Ore Deposit Geochemistry, {1. of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. China 2. {1. of Guizhou Provincial {2. of geology and Mineral Resoarces, Guiyang 550001. China Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China institute of Guizhou Provincial Bureau of Geology and Mineral Resources Guiyang 550001 China

1.Research significance and study area GEOCHEMISTRY of organic matter in metallic ore deposits and the role of organic matter in metallogenesisare the hot subjects of research in the field of ore deposits and also a weak link in this field. Widespreadin the areas of Tongren, Danzhai, etc. in eastern Guizhou (simplified as southeastern Guizhou or Qiandongnan below) are large-sized Hg (dominant), Sb, and Au deposits, while in the areas of Qinglong,Xingren, Zhenfeng, Anlong, etc. In southwestern Guizhou (simplified as southwestern Guizhou orQianxinan below) are a number of large-sized and extremely large-sized microfine disseminated gold deposits and Sb and Hg deposits. Studies have shown that their ore-forming temperatures are estimated al1.0℃ for Hg deposits, about 1.0℃ for Sb deposits and2.0℃ for most Au deposits, respectively, allof them belonging to the typical low-temperature deposits. Not a few researchers have found bitumens

关键词： organic matter fluid inclusion epithermal Hg-Sb-Au deposit.