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Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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Science china Earth Sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2, LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3.& WANG Xuance4 1. State Key Laboratory of Continental Dynamics, Department of geology, Northwest University, Xi`an 710069, china 2. State Key Laboratory of Geological Processes and mineral {3., china University of Geosciences, Wuhan 43.074, china 3. shenyang institute of geology and mineral resources, shenyang 110032. china 4. Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an China State Key Laboratory of Geological Processes and mineral resources China University of Geosciences Wuhan China shenyang institute of geology and {3. resources Shenyang China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2 = 52.82-59.3. wt%, Al_2O_3.14.15-16.3.wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03.1.88 μg/g) and Y(12-20 μg/g) and high Sr (620-13.3.μg/g) and Sr/Y(3.-88), withhigh La_N/Yb_N ratio (10-25). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(143.Nd/^(144)Nd(13.Ma) = 0.5118-0.5119, ε_(Nd) (13.Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (13. Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North china craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 120 to 13. Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2 for samples with SiO_2 > 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North china Craton, delamination.

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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 210008,china 2 Fairy Lake Botanical Garden,Shenzhen 518004,china 3.shenyang institute of geology and mineral resources,shenyang 11003.,china Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China Fairy Lake Botanical Garden Shenzhen 518004 China shenyang institute of geology and {3. resources Shenyang 110034 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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A New Fauna——Qinghezhen Fauna——from the Northern Margin of the North china Platform

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Acta Geologica Sinica(English Edition) 1990年第4期64卷 443-459,468-470页

作者： Liu Xiaoliang Wang Dongfang shenyang institute of geology and {3. resources, Chinese Academy of Geological Sciences Yue Zhao shenyang institute of geology and {3. resources Chinese Academy of Geological Sciences

In the Inner Mongolia axis and Jiaoliao anteclise along the northern margin of the North china *** has been found that the strata formerly considered as Archaean and Proterozoic are in fact an ophiolite suitesimilar to the Early Palaeozoic Ondor Sum Group in the Northern Geosyncline region of china. The stratahave been named in northern Liaoning as the Qinghezhen Group. The emphasis of this paper is on the discus-sion of the simall shelly fossils found in the siliceous rocks in the upper part of the Qinghezhen Group. Thisophiolite suite stretches in an E-W direction for about 1000 km along the northern margin of the North chinaPlatform. in which 15 fossil localities with stable stratigraphic horizons have been discovered. In this paper. 4types. 7 genera (including 5 new ones) and 10 species (including 8 new ones and 1 new subspecies) aredescribed, which are collectively referred to as the Qinghezhen Fauna. The characteristics of these fossils are:shell form simple. the maximum length not exceeding 4 mm. with obvious shell wall and wall ornaments. TheQinghezhen Fauna is comparable in shell structure of some genera and species with the Meishucun Fauna inSouth china, but differs from the latter in having only monotonous fossil groups developed in a distinctly va-ried ecological environment. The two faunas may belong to the same evolutionary stage of the Early Cambrianbut have developed parallelly in different regions. The existence of the Qinghezhen Fauna represents an impor-tant biological event in the Early Cambrian in the Northern Geosyncline region of china. The discovery of theQinghezhen Fauna will bring new knowledge and profound influence to a series of problems on basic geologyand mineral deposit prospecting such as the Cambrian faunas. biogeographical povincialism in china and thegeotectonic features of the northern margin of the North china Platform.

关键词： A New Fauna from the Northern Margin of the North china Platform

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Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2**) Zhang Hongfu~2 Liu Xiaoming~3.Li Zhitong~4 (1.School of Earth and Space Sciences,Peking University,Beijing 100871,china 2.institute of geology and Geophysics and Key Laboratory of {3. resources,Chinese Academy of Sciences,Beijing 100029,china 3.Key Laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,china 4.institute of geology and {3. resources of shenyang,shenyang {13.china) School of Earth and Space Sciences Peking University Beijing 100871 China institute of geology and Geophysics and Key Laboratory of mineral {3. Chinese Academy of Sciences Beijing 100029 China Key Laboratory of Continental Dynamics Northwestern University Xi'' an 710069 China institute of geology and mineral {3. of shenyang Shenyang 110032 China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 254 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

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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 {3. and mineral resources, Nanjing 210016, china 3. Tianjin institute of {3. and mineral resources, Tianjin 3.0170, china 4. The 2nd Regional Geological Investigation Party, Xinjiang Bureau of {3. and mineral resources, Changji 83.100, china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Nanjing institute of geology and mineral {3. Nanjing China Tianjin institute of geology and mineral {3. Tianjin China The 2nd 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 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 (50-220 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 T2DM model ages of 470 to 580 Ma and positive εNd(3.1 Ma) values of 6.23.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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Discovery of the Changtu Fauna in the Xia' ertai and Hulan Groups in Liaoning and Jilin and Its Significance

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Acta Geologica Sinica(English Edition) 1992年第4期66卷 427-438,445-447页

作者： Liu Xiaoliang Chen Congyun Yang Xuezeng Yang Sen Zhang Jiongfei Gao Yuhua shenyang institute of geology and {3. resources, Chinese Academy of Geological Sciences, shenyang, Liaoning Sun Sheping shenyang institute of geology and {3. resources Chinese Academy of Geological Sciences Shenyang Liaoning

The Ordovician Changtu Fauna is recently discovered in the Xia' ertai and Hulan Groups in northernLiaoning-central Jilin. The fauna, containing 10 genera and 14 species (including 3.new genera, 9 new speciesand an unidentified species), is closely related in evolution with the Early Cambrian Qinghezhen Fauna. Thediscovery of this fauna is significant to the study on the age of the strata, Ordovician biostratigraphy and geo-logical evolution of the tectonostratigraphical terrane on the northern margin of the Sino-Korean plate.

关键词： Northern Liaoning-central Jilin Ordovician Changtu Fauna

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Have a correct understanding of the attribute of geologic environmentgive full play to the role of geoscience in environmental protection

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Journal of Environmental Sciences 1995年第4期7卷 491-501页

作者： Ha Chengyou(institute of Environmental geology, Ministry of geology and {3. resources, Beijing 100081 , china)

Ｈａｖｅａｃｏｒｒｅｃｔｕｎｄｅｒｓｔａｎｄｉｎｇｏｆｔｈｅａｔｔｒｉｂｕｔｅｏｆｇｅｏｌｏｇｉｃｅｎｖｉｒｏｎｍｅｎｔｇｉｖｅｆｕｌｌｐｌａｙｔｏｔｈｅｒｏｌｅｏｆｇｅｏｓｃｉｅｎｃｅｉｎｅｎｖｉｒｏｎｍｅｎｔａｌ... 详细信息

ＨａｖｅａｃｏｒｒｅｃｔｕｎｄｅｒｓｔａｎｄｉｎｇｏｆｔｈｅａｔｔｒｉｂｕｔｅｏｆｇｅｏｌｏｇｉｃｅｎｖｉｒｏｎｍｅｎｔｇｉｖｅｆｕｌｌｐｌａｙｔｏｔｈｅｒｏｌｅｏｆｇｅｏｓｃｉｅｎｃｅｉｎｅｎｖｉｒｏｎｍｅｎｔａｌｐｒｏｔｅｃｔｉｏｎＨａＣｈｅｎｇ...

关键词： geologic environment attribute geologic resources geologic capacity geologic disaster.

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Relationships Between the North china Plate and the Tarim Plate

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 109-124,226页

作者： Wang Tingyin, Wang Jinrong, Liu Jinkun, D epartment of geology, Lanzhou U niversity, Lanzhou, GansuWang Shizheng, Ningxia Bureau of geology and mineral {3., Yinchuan, Ningxiaand Wu Jiahong shenyang institute of geology and mineral {3., shenyang, Liaoning Department of geology Lanzhou University Lanzhou Gansu China

The relationships and boundary between the North china and Tarim plates have been unclear for a long time ; however, the two plates occupy a prominent position in the formation and evolution of the continental lithosphere of china. It is proposed that the Engger Us ophiolitic melange zone discovered recently north of Alaxa is a typical suture between the two plates. The ophiolitic melange zone is composed mainly of a mixture of fragments of ancient oceanic crust and sedimentary rocks of active and passive continental margins. The melange may be divided into tectonic inclusions and matrix. The suture extends northeastwards into the Republic of Mongolia and probably westwards to meet the Altun fault. With the Engger Us ophiolitic melange zone as the boundary the Alaxa area may be divided into two parts: the northern part (AN ) belongs to the Tarim plate, while the southern part (AS) the North china plate. Geological evidence shows that the two plates were amalgamated in the Late Permian or a bit later.

关键词： North china plate Tarim plate ophiolitic melange tectonic evolution

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Continental- Margin Structure of Northeast china and Its Adjacent Areas

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 241-258页

作者： Tang Kedong, shenyang institute of geology and {3. resources, shenyang,Liaoning ProvinceWang Ying,Bureau of geology and {3. resources of Heilongjiang Province,Harbin, HeilingjiangHe Guoqi and Shao Ji’an Peking U niversity, Beijing Liu Xinzhu shenyang institute of geology and {3. resources Shenyang China

The continental margin of Northeast china and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to the evolution of the Palaeo-Asian Ocean and the south part to the evolution of the Palaeo - Pacific Ocean. The outer belt is a Mesozoic terrane, which is a melange made up of fragments of the Late Palaeozoic to Early Mesozoic oceanic crust and the Late M esozoic trench *** existed another ocean-the Palaeo - Pacific Ocean during the period from the closing of the Palaeo-Asian Ocean to the opening of the modern Pacific Ocean or from the Devonian to Jurassic, and the ocean-floor spreading of the Palaeo - Pacific Ocean led to the formation of the above-mentioned tectonic belts. The development of the strike-slip fault system after the Late Jurassic and the formation of an epicontinental volcano -plutonic rock belt in the Late Cretaceous to Early Tertiary are attributed to the interaction between the modern Pacific plate and the Eurasian plate.

关键词： continental-margin structure Bohai Sea block Mesozoic terrane non- subducted ocean crust Palaeo - Pacific Ocean

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Combination of drainage, water supply and environmental protection as well as rational distribution of water resource in Zhengzhou mining district

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Science china Earth Sciences 2005年第10期48卷 1768-1779页

作者： WU Qiang1, LI Duo1,2, DI Zhiqiang3. MIAO Ying3. ZHAO Suqi4 & GUO Qiwen5 1. Resource Exploitation Engineering College, CUMT, Beijing 100083. china 2. Shijiazhuang Engineering College, University of Economics, Shijiazhuang 05003., china 3. shenyang institute of geology and mineral resources,{3. 4. State Adminstration of Coal Mine Safety, Beijing 100013. china 5. Zhengzhou Coal Mine Company (Group), Zhengzhou 4523.1, china Resource Exploitation Engineering College CUMT University of Economics shenyang institute of geology and {3. resources State Adminstration of Coal Mine Safety Zhengzhou Coal Mine Company (Group)

The geological condition of coalfield is much complex in china. With increasing in mining depth and drainage amount, the contradiction of drainage, water supply and environ-mental protection is becoming more and more serious. However, the contradiction can be solved by the scientific management of optimizing combination of drainage, water supply and environ-mental protection. The Philip multiple objectives simplex method used in this article has searched for a possible solution at the first step, and then it goes on searching to find out whether there is a weight number that can lead the solution to the biggest. It can reduce the randomness and diffi-culty of traditional weight method which determine the weight number artificially. Some beneficial coefficients are vague and the number is larger in the model of water resource dispatch. So the vague layer analysis method can consider these vague factors fully, combining the qualitative and quantitative analysis together. Especially, this method can quantify the experiential judge-ment of policy decider, and it will turn to be more suitable if the structure of objective factors is complex or the necessary data are absent. In the paper, the two methods above are used to solve the plans of drainage, water supply and optimizing distribution of water resource in the Zhengzhou mining district.

关键词： combination of drainage, water supply and environmental protection, Philip multiple objective simplex method, vague layer analysis method, distribution of water resource.

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