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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 Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China nanjing Institute of geology and {2. resources Nanjing China Tianjin Institute of geology and mineral {2. Tianjin China The 2.d Regional Geological Investigation Party Xinjiang Bureau of Geology and Mineral Resources Changji 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.

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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 geology and mineral resources, Yichang 443003, china 3. Hainan Bureau of geology and mineral resources, Haikou 5702.6, china State Key Laboratory for mineral Deposits Research and Department of Earth Sciences Nanjing University Nanjing China Yichang Institute of geology and mineral {2. Yichang China Hainan Bureau of geology and mineral {2. Haikou 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―2.12., 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―0.7142. 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.

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Petrogenesis and significance of early Yanshanian syenite-granite complex in eastern Nanling Range

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Science china Earth Sciences 2005年第7期48卷 912-924页

作者： CHEN Peirong1, ZHOU Xinmin1, ZHANG Wenlan1, LI Huimin2. FAN Chunfang1, SUN Tao1, CHEN Weifeng1 & ZHANG Min1 1. State Key Laboratory of mineral Deposits Research, Department of Earth Sciences, nanjing University, nanjing 2.0093, china 2. Tianjin Institute of geology and mineral resources, china Geological Survey, Tianjin 300170, china State Key Laboratory of mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China Tianjin Institute of geology and mineral {2. China Geological Survey Tianjin 300170 China

In the eastern Nanling Range there exists the early Yanshanian syenite-granite assemblage. A representative example is the Pitou-Tabei complex composed of the Tabei syenite pluton and the Pitou syenogranite pluton in southern Jiangxi Province. U-Pb zircon dating yields ages of 188.6±2.2.Ma for the Tabei pluton and 186.3±1.1 Ma for the Pitou pluton. The Tabei syenite is characterized by relatively low SiO2.content (62.40% - 68.75%), high alkalis (K2.+Na2. = 10.56%-11.96%), low percent K2./Na2. ratios (0.56-0.93), metaluminous fea- ture (A/CNK = 0.80-1.00), enrichment in LILE (Rb, Ba, K) and HFSE (Th, U, Nb, Ta, Zr, and so on), weakly negative to positive Eu anomalies (δ Eu = 0.63-1.82., relatively low (87Sr/86Sr)i (0.70412.0.70543), and relatively high ε Nd(t) (3.14-3.52.. The Pitou syenogranite is charac- terized by high silicon content (SiO2.= 71.06%-76.2.%), relatively low alkalis (K2.+Na2. = 8.10%-9.80%), high percent K2./Na2. ratios (1.2.-1.94), metaluminous feature (A/CNK = 0.94-1.07), enrichment in Rb, Th (U), K, depletion in Ba, Nb, Ta, Sr, P , Zr, Ti, high ΣREE (av- eraging 451.03 μg/g), strong negative Eu anomalies (δ Eu = 0.2.-0.33), relatively high (87Sr/86Sr)i (0.70805-0.70912., and relatively low ε Nd( t ) (?5.35-?6.2.). The Tabei syenite and Pitou syenogranite both have the characteristics of A-type granites. The former is considered to be from the asthenosphere mantle, and the latter was the product of the crust-mantle mixture. They both were probably formed in a rifting setting.

关键词： syenite-granite assemblage single zircon U-Pb age rifting environment Nanling Range.

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The geological feature, geochemistry and origin of Jinya gold deposit in Fengshan, Guangxi

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Chinese Science Bulletin 1999年第S2期44卷 168-169页

作者： ZHOU Jiyuan~1, CUI Bingfang~1 and LU Yan~2.1. nanjing Institute of geology and {2. resources, nanjing 2.0016, china 2. Chengdu Institute of Technology, Chengdu 610059, china nanjing Institute of geology and {2. resources Nanjing 210016 China Chengdu Institute of Technology Chengdu 610059 China

1 Geological feature of deposit The Jinya gold deposit is a fine disseminated gold mine. It occurs in sandstone and mudstone ofMiddle-Triassic Baifeng Formation, which is located at the margin of Late Paleozoic carbonate platform. Itwas controlled by the fracture zone, cleavage zone and fissure zone. The gold deposit has 15 orebodies,which are displayed as beds, lens and veins. The dominating minerals with gold are pyrite and arsenopyrite. The gold mainly occurs as submicroscopic intergranular gold. Low-to-moderate temperature (130-305℃) wall-rock alterations are mainly silicification, pyritization and arsenopyrite, also includes realgarization, carbonation (calcite, dolomite), sericitization and argillation (kaolinite, pyrophyllite). It wasformed after undergoing the sedimentary diagenetic period, hydrothermal mineralization epoch (2.3 Ma)and supergene mineralization.

关键词： geological feature Jinya gold deposit Fengshan.

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Discovery of sponge body fossils from the late Meishucunian (Cambrian) at Jinsha, Guizhou, south china

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Progress in Natural Science:Materials International 2005年第8期15卷 708-712页

作者： YANG Xinglian 1,2., ZHAO Yuanlong2. WANG Yue2.and WANG Pingli2.1. nanjing Institute of geology and Palaeontology, Chinese Academy of Sciences, nanjing 2.0008, china 2. Institute of Resource and Environment, Guizhou University, Guiyang 550003, china) nanjing Institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China Institute of Resource and Environment Guizhou University Guiyang 550003 China

Here we report discovery of a sponge body fossil Triticispongia sp. from the base of lower Cambrian Niutitang Formation at Jinsha, Guizhou. Stratigraphically, the fossil horizon is located below Ni-Mo ore layer with the Niutitang Biota above, and is equivalent to the late Meishucunian. The species is global in shape with skeletons composed of stauractins and monaxons. Triticispongia sp. reported here may be the earliest sponge body fossils of Cambrian, which provides new information for understanding early evolution and radiation of sponge animals.

关键词： sponges Cambrian Niutitang Formation Guizhou china.

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Pollen records of Holocene vegetation and climate changes in the Longzhong Basin of the Chinese Loess Plateau

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Progress in Natural Science:Materials International 2007年第12期17卷 1445-1456页

作者： Tang Lingyu1 and An Chengbang2.1. nanjing Institute of geology and Paleontology, Chinese Academy of Sciences, nanjing 2.0008, china 2. Key Laboratory of Western china’s Environment Systems, MOE, Lanzhou University, Lanzhou 730000, china) nanjing Institute of geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China Key Laboratory of Western china's Environment Systems Lanzhou University Lanzhou 730000 China

Pollen records with an average time resolution of 2.-2.0 years from Holocene loess sections at Dingxi, Qin'an, and other localities of Gansu Province reveal a detailed history of vegetation and climate changes in the western Loess Plateau. For most time of the Holocene, the landscape was dominated by grasslands or forest steppes. However, during the middle Holocene (7.5-5.8 ka BP), relatively dense forests developed, and the endemic vegetation flourished, suggesting a much warmer and more humid climate condition than the present. Superimposed upon this general pattern are several dry intervals marked by the episodic expansion of grasslands or forest steppe. Xeric vegetation expanded after 3.8 ka BP, indicating a trend towards dry conditions.

关键词： pollen records glasslands coniferous forests Holocene Loess Plateau.

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Whole fossil plants of Ephedra and their implications on the morphology,ecology and evolution of Ephedraceae (Gnetales)

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Chinese Science Bulletin 2010年第15期55卷 1511-1519页

作者： WANG Xin 1,2.& ZHENG ShaoLin 3 1 nanjing Institute of geology and Palaeontology,Chinese Academy of Sciences,nanjing 2.0008,china 2.Fairy Lake Botanical Garden,Shenzhen 518004,china 3 Shenyang Institute of geology and mineral resources,Shenyang 110034,china nanjing Institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China Fairy Lake Botanical Garden Shenzhen China Shenyang Institute of geology and mineral {2. Shenyang China

Although there are many reports of fossil Ephedraceae,whole plant fossil record remains *** to a lack of trust on partially preserved fossil materials,scholars working on molecular clock proposed a recent origin of Ephedra and cast doubt on the earlier origin time of *** better the understanding on this interesting group,here we report whole plants of Ephedra hongtaoi ***.(Ephedraceae,Gnetales) from the Yixian Formation (Early Cretaceous) in western Liaoning,*** whole plants of Ephedra demonstrate clearly the characters of Ephedra,including shrubby growth habit,decussate branching pattern,and terminal ovuliferous unit with micropylar *** whole-plant preservation of the fossils provides more convincing fossil evidence of Early Cretaceous Ephedra,helps to resolve the controversy over the origin time of Ephedra,and sheds light on the whole plant morphology,growth habit,ecology and evolution of Ephedraceae.

关键词：化石植物生态学麻黄形态学进化材料保存早白垩世生长习性

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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 Seismological Bureau, Beijing 10002., china Department of Earth Sciences and State Key Laboratory for mineral Deposits Research Nanjing University Nanjing China Institute of geology China Seismological Bureau 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 1186 Ma to 112. 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.

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Refinement of the crystal structure for a new mineral──antimonselite

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Chinese Science Bulletin 1998年第5期43卷 413-416页

作者： MIN Maozhong 1, ZHAI Jianping 1, WANG Xiangyun 1,SHEN Baopei 2. WEN Guangdou 2.and FAN Tao 2.. Department of Earth Sciences, nanjing University, nanjing 2.0093,{2. 2. Uranium geology Bureau of Central-South{2., Changsha 410000,{2. Department of Earth Sciences Nanjing University Nanjing China Uranium geology Bureau of Central-South china Changsha China

The crystal structure of a new mineral of the stibnite group, Sb-2.e-3, has been determined. The cell constants, obtained by least-squares calculation from direct θ -value’s measurements on the diffractometer are: a =1.158 8(5), b =1.174 4(4), c =0.395 5(2. nm; orthorhombic; V =0.538 2. nm+3; Z =4. The space group is Pbnm. X-ray single crystal data, using Mo K α radiation, were measured on a RIGAKU RASA-5RP automated diffractometer and refined to a final R index of 0.048 1. Sb-2.e-3 is isostructural with Sb-2.-3 and Bi-2.-3. Each Sb(1) atom is six-coordinated by 3 Se(1), 1 Se(2. and 2.Se(3) atoms at distances 0.2.6 0-0.32. 6 nm. Each Sb(2. atom is seven-coordinated by 2.Se(1), 2.Se(2. and 3 Se(3) atoms at distances of 0.2.8 1- 0.346 7 nm. The crystal structure consists of chains parallel to c or needle axis. The strongest bonds (shortest separations) are within the chains. Many important physical properties of antimonselite (optical, ferroelectric, etc.) are related to its crystal structure.

关键词： new mineral antimonselite crystal structure.

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Schmeissneria:An angiosperm from the Early Jurassic

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Journal of Systematics and Evolution 2010年第5期48卷 326-335页

作者： 1,2.in WANG 1(nanjing Institute of geology and Palaeontology,Chinese Academy of Sciences,nanjing 2.0008,china) 2.Fairylake Botanical Garden,Shenzhen 518004,china) (nanjing Institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China) (Fairylake Botanical Garden Shenzhen 518004 China)

The origin of angiosperms has been a focus of intensive research for a long *** so-called pre-Cretaceous angiosperms,including Schmeissneria,are usually clouded with *** expel the cloud around the enigmatic Schmeissneria,the syntype and new materials of Schmeissneria collected previously in Germany and recently in china are *** materials include female inflorescences and *** latter are old materials but were under-studied *** microscopy and scanning electron microscope observations indicate that the fruits in these infructescences have in situ seeds enclosed,and that the ovaries are closed be fore *** the plants meet two strict criteria for angiosperms:angiospermy plus *** Schmeissneria in angiosperms will extend the record of angiosperms up to the Early Jurassic,more compatible with many molecular dating conclusions on the age of angiosperms,and demanding a reassessment of the current doctrines on the origin of *** the phylogenetic relationship of Schmeissneria to other angiosperms apparently is still an open question,this study adds to research concerning the origin of angiosperms.

关键词： angiosperm earliest evolution flower fossil Germany Jurassic origin.

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