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Mineral Phase Transformation and Water Fluid Evolution of Khondalite Series in the Border Area of Shanxi and Inner Mongolia,China

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Continental Dynamics 1999年第1期 62-69页

作者： LIU Fulai institute of geology, Chinese academy of {2. {3., beijing 100037, China

Typical Precambrian khondalite series is widely exposed in the border area of Shanxi and Inner Mongolia, and is composed primarily of sillimanite garnet biotite gneiss (SS), garnet pyroxene biotite gneiss (GS) and attendant migmatitic gneiss. According to the characteristics of multistage reaction texture and mineral phase transformation, the mineral assemblage of the khondalite series can be divided into three generations: ① peak stage (M 1) mineral assemblage, involving hydrous biotite, is composed of Sil+Gt+Bi+Kf±Pl+Qz in the SS and Gt+Opx+Bi+Kf+Pl+Qz in the GS, formed at T=750℃-850 ℃ and P=0.80-0.95 GPa. Water activity (a H 2. ) of this stage was about 0.2.-0.3. (0.2.±) in the SS and 0.3.-0.53.(0.45±) in the GS; ② in the post peak retrograde near isothermal decompression stage (M 2., the khondalite series of the study region is characterized by dehydration reaction of biotite, partial melting of felsic minerals and decompression texture of garnet. Sillimanite garnet migmatitic gneiss (SMS) and garnet pyroxene migmatitic gneiss (GMS) were formed at this stage. The attendant anhydrous mineral assemblages are Sil+Gt+Crd+Kf±Pl+Qz in the SMS and Gt+Opx+Crd+Kf+Pl+Qz in the GMS, formed at T= 73. ℃ - 82. ℃ and P=0.50-0.65 GPa. However, the water activity (a H 2. ) of this stage was reduced to 0.08-0.12.( 0.09± ) in the SMS and 0.13.-0.18 (0.15±) in the GMS, and ③ in the later cooling stage (M 3. of metamorphism, fine grained hydrous vermicular symplectite Bi+Kf replaced anhydrous garnet at T=500 ℃-560 ℃and P=0.3.-0.44 GPa, indicating that the water activity (a H 2. ) of M 3.increased again. Research results suggest that the border conditions of mineral evolution and (dehydration) metamorphic reactions are not only controlled by PT conditions, but also genetically related to water activity evolution in the khondalite series of the study region.

关键词： Metamorphic reaction water activity khondalite series Shanxi and Inner Mongolia

Orogenic and Anorogenic Granitoids in the Altay Mountains of Xinjiang and Their Discrimination Criteria

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 45-64页

作者： Zou Tianren institute of Mineral Deposits, Chinese academy of {2. {3., beijing Chao Huizhi and Wu Baiqing Xinjiang institute of geology, Ministry of Metallurgical Industry Urumqi, Xinjiang Jiang Minxi 1Teliti and Yang Yueqing also participated in the field work. Those who participated in the laboratory study also include Yang Bingbin Duan Shangzhi Lü Qiaoling Li Longqi and Yu Shimei.

On the basis of field geological studies of the granotoids in the region, mineralogical, petrological, geochemical(including stable isotope geochemical) and isotopic geochronological investigations were carried out on selected representative granitic bodies of various types. The authors have concluded that, apart from the bodies of the orogenic granitoid series, there also exist intrusions of the anorogenic granitoid series in the region. The intrusives of the two series were formed not only in different ages and tectonic environments, but also were derived from different sources of materials. Moreover, they are associated with different mineralizations, belonging to different minerologenetic series(Cheng et al., 1983.. They show distinctly a series of discriminative criteria. The problems under discussion in the present paper are of important theoretical and practical significance in the studies of granites of the orogenic belt, particularly the studies of the genesis and related metallogeny of the granites of the region.

关键词： Orogenic and Anorogenic Granitoids in the Altay Mountains of Xinjiang and Their Discrimination Criteria

Barium Anomaly and Its Geochemical Significance

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Continental Dynamics 1999年第1期 84-87页

作者： WANYusheng institute of geology, Chinese academy of {2. {3., beijing 100037 , China

In the MORBnormalized multi element variation diagram given by Pearce(1983. ,the depletions of Ba relativeto Rb and Th are differentfor *** the case ofthe Eu anomaly ,the Ba anomaly can be defined and calculated . The Ba and Eu anomalies show close positive relationships with each other. The geochemicalsignificance ofthe Ba anomaly is discussed in this paper. Key words: Ba anomaly ; Eu anomaly; GeochemistryBarium Anomaly and Its GeochemicalSignificance WANYusheng institute of geology, Chinese {2. of {2. {3., beijing 100037 , China Abstract In the MORBnormalized multi element variation diagram given by Pearce(1983. ,the depletions of Ba relativeto Rb and Th are differentfor *** the case ofthe Eu anomaly ,the Ba anomaly can be defined and calculated . The Ba and Eu anomalies show close positive relationships with each other. The geochemicalsignificance ofthe Ba anomaly is discussed in this paper.

关键词： Ba anomaly Eu anomaly Geochemistry

The Yadong-Golmud Geoscience Transect in the Qinghai-Tibet Plateau

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Acta Geologica Sinica(English Edition) 1990年第2期64卷 115-127页

作者： Wu Gongjian Xiao Xuchang Li Tingdong Chinese academy of geological {2., {3. Jia Zhongpeng Chinese academy of geological {2. Beijing 1This project was financially supported by the National Natural Science Foundation of China and the Min-istry of geology and Mineral Resources.

On the basis of abundant geological and geophysical data. 6 terranes have been distinguished on theQinghai-Tibet Plateau. The plateau is a single integrated lithospheric unit although it is divided into blocks.With Amdo as a boundary. the crust may be divided into two parts with different crustal structures. The struc-ture in the southern part is complex, while that in the northern part is simple. The current study has revealedthat 8 factors such as slab subduction. overthrust and superimposition are responsible for crustal shorteningand thickening in the region. The uplift of this region is possibly due to northward compression of the Indianplate and southward compression of the Eurasian plate with the former predominating. The compression led tothe asthenospheric movements which were also influenced by thermal activity caused by doming at the bound-ary between the core and mantle.

关键词： The Yadong-Golmud Geoscience Transect in the Qinghai-Tibet Plateau

Experimental Study on the Leaching of Gold from Greenstone

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Acta Geologica Sinica(English Edition) 1993年第2期67卷 211-221页

作者： Liu Yushan, Zhang Guilan institute of Mineral Deposits, Chinese academy of {2. {3., beijing and Tian Jun Changchun College of geology, Changchun, Jilin institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing China

Experiments were conducted on the leaching of gold from greenstone by chloride solution under the temperature of 2.0—550℃ and the pressure of 60 MPa. During part of the experiments, the oxygen fugacity was controlled. The results show that the leaching rate of gold is related to temperature, composition of the solution, pH and oxygen fugacity. In the experiment with oxidative acidic solution, the leaching rate was up to 50％ or more. It is known that the leaching of gold is restricted by the reaction in which the gold is dissolved from the rock to form gold chloride complex. Therefore, the authors hold that the acidic chloride solution derived from granite magma has caused the remobilization-migration of gold from greenstone and its enrichment into ore.

关键词： leaching gold deposits greenstone

Discovery of Enclaves from Cenozoic PuluVolcanic Rocks in West Kunlun Mountains and Itsgeological Implications

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Journal of China University of Geosciences 2002年第1期13卷 30-34页

作者： Zhang Zhaochong Xiao Xuchang Wang Jun Wang Yonginstitute of geology , Chinese {2. of {3. sciences, beijing 100037 institute of geology Chinese Academy of Geological Sciences Beijing 100037

In this paper, we present the occurrence and mineral components of the enclaves firstly discovered in the Cenozoic Pulu volcanic rocks in west Kunlun Mountains, and propose that the enclave is accumulated by fractional crystallization within high-level magma chamber. In addition, the chemical compositions of its primary magma are calculated. The calculated compositions are similar to those of the Kangxiwa volcanic rocks that belong to the same volcanic belt in the Pulu volcanic region, suggesting their origin from the same source region. However, the temperatures and oxygen fugacity of magmas at high-level magma chamber decreased along with fractional crystallization.

关键词： enclave fractional crystallization volcanic rocks West Kunlun Mountains.

Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science China Earth sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2. LU Xinxiang1,3. WANG Fei4, SUN Yangui5, WEI Xiangdong3.& XING Zuoyun6 1. Division of Granite {2., China geological Survey, Yichang 443.03. China 2. Information {2. of Ministry of Land and Resources, {3. 100812. China 3. geological Survey of Henan Province and institute of geological Research of Henan Province, Zhengzhou 450053. China 4. geological institute, China Seismological Bureau, {3. 10002., China 5. geological Survey institute of Qinghai Province, Xining 81003., China 6. China University of Geo{12., Wuhan 43.074, China Division of Granite geology China Geological Survey Yichang 443003 China Information center of Ministry of Land and Resources Beijing 100812 China geological Survey of Henan Province and institute of geological Research of Henan Province Zhengzhou 450053 China geological institute China Seismological Bureau Beijing 100029 China geological Survey institute of Qinghai Province Xining 810032 China China University of Geosciences Wuhan 430074 China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in China, which was found after the discovery of Shachang rapakivi in Miyun County, beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North China plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±3.)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (52. 2.1) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western China and the basement of the North China plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient China continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

Reinterpretation of the Guangxian Orogeny

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Chinese Science Bulletin 2000年第13期45卷 1244-1248页

作者： WU Haoruoinstitute of geology and Geophysics, Chinese {2. of {3., beijing 10002., China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

The Guangxian Orogeny, as an important concept on geology of South China, was created 70 years ago. It is generally regarded as an erogenic movement caused by the convergence of the Cathaysian and Yangtze blocks at the end of Silurian. Based on the recent progress of the geological research on Guangxi and adjacent areas, western Guangxi and Liuzhou-Heshan area of central Guangxi may belong to a stable block of Early Paleozoic. The Guangxian Orogeny originated from the northward translation of the Yunkai Block on its south at the end of Cambrian, and formed the Damingshan-Dayaoshan fold belt between the two blocks. It was possibly related with the Late Pan-African Orogeny. The convergence of the Cathaysian and Yangtze blocks occurred in Late Ordovician to Early Silurian and mainly had effect on Hunan and Jiangxi provinces. The term 'Chongyu Orogeny' may be suitable for it. At the end of Silurian orogenic movement did not occur in this area.

关键词： South China tectonics Paleozoic Guangxian Orogeny Yunan Orogeny Chongyu Orogeny.

geology　AND　GEOCHEMISTRY　OF　THE　SHUIQUANGOU　COMPLEX，　NORTHERN　HEBEI　PROVINCE，　CHINA

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Scientia Geologica Sinica 1996年第4期 447-468页

作者： Zhang Zhaochong(institute of geology, Chinese {2. of {3. sciences, beijing 100037)Chen Hongxin(institute of Geomechanics, Chinese {2. of {3. sciences, beijing 100081)

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