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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 {3. resources, Nanjing 2.0016, China 3. tianjin institute of geology and mineral resources, tianjin 3.0170, China 4. The 2.d Regional Geological Investigation Party, Xinjiang Bureau of {2. and {3. resources, Changji 83.100, China 1. Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 2. Nanjing institute of geology and {2. {3. Nanjing 210016 China 3. tianjin institute of geology 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 3.0.7±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(3.1 Ma) values of 6.2.0}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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The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, China

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Science China Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3.& WANG Lei2.1. institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2. Faculty of Earth Sciences and {2. {2., China University of Geosciences, Beijing 100083. China {3., tianjin 3.0170, China 1. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth Sciences and mineral resources China University of Geosciences Beijing 100083 China 3. tianjin institute of geology and mineral resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

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Analytical Model for the Palaeoenvironmental Evolution of the Nihewan Beds

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 77-86页

作者： Yue Jun Wen Qizhong tianjin institute of {2. and {3. resources institute of Geochemistry, Academia Sinica tianjin institute of {2. and {3. resources China

In this paper, the evolutional characteristics of palaeoclimate and oxidation-reduction conditions as well asacidity-alkalinity environment are discussed by means of the step-regression, cluster, optimal partitioning andcorrelation analyses of CaCO_3. C / P_2._5, Fe^(2.) / Fe^(3.), pH and Eh values, taking the Xiaodukou section in theNihewan basin as an example. The CaCO_3. C / P_2._5 and pH were calculated respectively using the optimalpartitioning method. Thus five cold zones and six warm zones as well as five reduction and six oxidation zoneswere distinguished. Then the inductive method was used to produce four numerical groups: 8.10, 8.3.8.4,8.6-8.7 and 8.9-8,97. The above-mentioned results are respectively based on CaCO_3.content, C/P_2._5 andpH values. From Fig. 3. Tables 1 and 2.it can be seen that the Nihewan Beds were formed mainly under a re-duction and slightly alkaline environment of cold climate, with pH values of 8.3.8.4. Fig. 3.shows that bed 3.is approximately near the boundary between the Brunhes and Matuyama polarity epochs, 0.73.Ma in age; bed2. is roughly near the Jaramillo event (base), 0.97 Ma in age; bed 18 coincides roughly with themagnetostratigraphic boundary of 2.00 Ma (?). Bed 13.may be the Pleistocene-Pliocene boundary, 2.48 Ma inage. Thus geochemical zones Ⅰ, Ⅱ, Ⅲ and Ⅳ include respectively cold zones 1; 2.and 3. 4; and 5.

关键词： Analytical Model for the Palaeoenvironmental Evolution of the Nihewan Beds

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Gymnosperms on the eve of the terminal Permian mass extinction in North China and their survival strategies

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Chinese Science Bulletin 1998年第11期43卷 889-897页

作者： WANG Ziqiang+1 and ZHANG Zhiping+2. 1. tianjin institute of {2. and {3. resources, Chinese Academy of Geological Sciences, tianjin 3.0170, China 2. tianjin Centre of Physical and Chemical Techniques, tianjin 3.0050, China tianjin institute of {2. and {3. resources Chinese Academy of Geological Sciences Tianjin China tianjin Centre of Phyhical and Chemical Techniques Tianjin China

Main characteristics of the Permian redbed gymnosperms in North China have been summarized: dominant peltasperms and conifers, numerous enigmatics such as Gigantonoclea and Psygmophyllum, and abundant precursors of Mesozoic gymnosperms. Furthermore, stresses affecting these plants survival are suggested to be paleoatmospheric CO-2.concentration, water stress, wind and fire activities, and fungal infection. Consequently, a preliminary analysis accounts for the ecological strategies of these gymnosperms to the P-Tr event.

关键词： North China Permian gymnosperms mass extinction.

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Terminal Precambrian Palaeogeographic Framework of China

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 115-125页

作者： Qiao Xiufu, Ma Lifang Geological institute, CAGS, Beijing, and Zhang Huimin tianjin institute of {3. and mineral resources, CAGS, tianjin Jia Zhongpeng Geological institute CAGS Beijing China

The original locations and relationships of four plates within the mainland of China from 800 to 600 Ma during the terminal Precambrian were reconstructed based on the palaeomagnetic and geological data. The Tarim, Yangtze and Cathaysian plates were once linked (in 800-700 Ma) and located in the same low-latitude zone of the northern hemisphere. But later, in 700-600 Ma, the Tarim plate was separated from the Yangtze-Cathaysian plate. The Sino-Korean plate was always far away from the Yangtze plate, both being separated by oceanic crust, and lay in the high-latitude zone of the northern *** above-mentioned palaeogeographic framework directly led to complete differences in respect to distribution of low-latitude glaciation, sedimentary facies, palaeoclimate, palaeobiogeography and stratigraphic sections between the North and South China domains during the terminal Precambrian.

关键词： Terminal Precambrian Palaeogeographic Framework of China

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FOSSIL HAGLIDAE(ORTHOPTERA)IN CHINA

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Science China Chemistry 1982年第10期29卷 1118-1132页

作者：洪友崇 tianjin institute of {2. and {3. resources Ministry of Geology

The present paper discusses Haglidae (Orthoptera) and its stratigraphic and geographicdistributions in China. Basing on our fossil specimens and the known fossil records of insectsthe author tries to discuss the taxonomy of the family Haglidae, including its subfamilies andgenera. Four new genera and seven new species are established.

关键词： Cu FOSSIL HAGLIDAE ORTHOPTERA)IN CHINA length

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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. {2. {2. of {3. and mineral resources, China Geological Survey, tianjin 3.0170, China State Key Laboratory of mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China tianjin institute of {2. and {3. resources 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.-0.3.), relatively high (87Sr/86Sr)i (0.70805-0.70912., and relatively low ε Nd( t ) (?5.3.-?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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DISCOVERY OF NEW FOSSIL SPIDERS IN AMBER OF FUSHUN COALFIELD

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Science in China,Ser.B 1982年第4期25卷 431-437页

作者：洪友崇 tianjin institute of {2. and {3. resources Ministry of geology

A new genus, Sinodictyna （Archanda）, has been obtained from amber on the main coalbeds of the Gucheggzi Formation (E2.1), Fush?n Coalfield In Liaoning Province. It suggeststhat Sinodictyna belongs to a regional form in China and that it differs from European Balticamber Eolathys in the chelate teeth, pedipal, walking legs and its appendages. New genusdiscovered first in China fills in tlie gaps in the field of paleontology of China.

关键词： length

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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 {2. and mineral resources, Yichang 443.03. China 3. Hainan Bureau of {2. 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―2.12., 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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SHALE-FACIES MICROFLORA FROM THE CHANGZHOUGOU FORMATION (CHANGCHENG SYSTEM) IN PANGJIABU REGION, HEBEI, CHINA

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微体古生物学报 1991年第2期 191-193页

作者： Yah Yu-zhong (tianjin institute of {2. and {3. resources, Chinese Academy, of Geological, Sciences, tianjin 3.0170)

Abundant and diverse microflora were discovered in the black shales of the Changzhougou Formation of the Changcheng System in the Pangjiabu Region of Hebei, located in the western part of the Yanshan Mountains. The microflora assemblage consists of 3.groups, 2. genera, and 75 species, including 2.new genera, 7 new species and 3.affinities. Systematic comparison of the obtained microfossils with the shale-facies

关键词： body SHALE-FACIES MICROFLORA FROM THE CHANGZHOUGOU FORMATION IN PANGJIABU REGION HEBEI CHINA length CHANGCHENG SYSTEM

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