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    2016, Volume 23 Issue 4
    15 July 2016
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    Re understanding of some important basic geological issues about Dabieshan and its adjacent regions, China: A further study on the nonplate collision orogenic process of the Dabie Orogen Belt.
    SHANG Jia-Fu, HOU Meng-Jin
    2016, 23(4): 1-21. 
    DOI: 10.13745/j.esf.2016.04.001

    Abstract ( 3624 )   PDF (5047KB) ( 8855 )  

    Some important basic geological issues about Dabieshan and its adjacent regions have been expounded in detail in this paper, and further defined that (1) North Huaiyang region belongs to the northern margin of Yangtze Block, the boundary between it and the southern margin of the North China Landmass is the north of GushiFeizhong Fault Zone; that (2) Neoproterozoic lowgrade metamorphic rock series certainly existed in the ultrahigh pressure metamorphosed belt, it has undergone two phases of fold deformation with the eclogite and other ultrahigh pressure rocks, forming a deformed belt which was extensional detachment in the early stage, and contractive compression in the major stage, which are not the foreign tectonic remnants or tectonic accretionary wedge caused by the subduction process; that (3) the Blue Schist was formed during the extensional detachment, eclogites are pyrolite and magmatic origin, and other ultrahighpressure rocks and “coesite” could be formed by the joint action of the “Earths crust abnormal pressure ” and “high pressure autoclave”, in the extensional detachment environment within the entire shallow crust; that (4) widespread Neoproterozoic volcanic and intrusive rocks represent the intense tension cracking expansion event occurred during the Jinningian, but no ocean crust type basin formed; that 5. the characteristics and forming mechanism of the stretching and growth lineation in Dabieshan and its adjacent regions have been described in detail, and this paper suggests that it was formed in extensional detachmentslip shear process within the lithosphere and different layers of crust caused by “mantle differential circulation”. The Dabie Orogen Belt has undergone multistage tectonic movements, including cracking into a basin, extensional detachment, compressive squeezing and thermal uplift to form mountains, which was not formed by platecollision orogenesis.

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    New progress and understanding of the Baidashan group, southern margin of the North China Block.
    ZHANG Chun-Lei, CHA Shi-Xin, BI Chi-Guo, GONG Wei-Chi, JIA Qiong, MA Guo-Meng, GAO Ya
    2016, 23(4): 22-28. 
    DOI: 10.13745/j.esf.2016.04.002

    Abstract ( 3499 )   PDF (1238KB) ( 8354 )  

    Recently, the author has measured Baidashan group section which exposed a sequence of complete and continuous layer on the HenanAnhui border of southern margin on the north China Block. There are conodonts molecules of the MiddleLate Ordovician in carbonatite of Baidashan group: Belodina compressa,Panderodus gracilis,Pseudobelodina dispansa(?) and Bryozo, Calthrop, Small shells, Archaeostraca etc., which filled the blank of the region that has been no fossil record. According to the characteristics of stratigraphic sequence, lithologic combination, the biota appearance, the ancient sedimentary environment of geography, and combined with a large number of limestone thin section results, it is concluded that the Baidashan group belongs to the Early Paleozoic era. The southern margin of North China massif line was redrawn to JiangjiLongtan sets. We consider that the conodonts biota in this area should belong to the northern type conodonts geographical partition.

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    CHAI Guanglu, LI Shuangying. Geochemical characteristics and geological implications for the metamorphic rocks of Foziling Group in Eastern of North Huaiyang Tectonic Belt.
    CHAI An-Lu, LI Shuang-Ying
    2016, 23(4): 29-45. 
    DOI: 10.13745/j.esf.2016.04.003

    Abstract ( 3431 )   PDF (2220KB) ( 8313 )  

    Foziling group of North Huaiyang is a set of lower metamorphic rocks which had undergone multiple deformations and metamorphism. The average contents of Foziling Group are SiO2 75.42%, Al2O3 8.13%, MgO 1.52%, Fe2O3 3.23%, Na2O 1.61%, K2O 1.67%, TiO2 0.41%; a part of characteristic trace elements like Th, U, Hf, Sc, Zr, Y have average of 8.49×10-6, 1.47×10-6, 4.85×10-6, 170.66×10-6, 193.69×10-6 and 18.97×10-6, respectively; and the ratio of Th/U, La/Y, Th/Sc, La/Sc are respectively 4.92, 3.56, 1.51 and 1.38; the average of ∑REE is 125.3×10-6, δEu is 0.67, light REE enrichment, La/Yb is 14.99 and (La/Yb)N is 10.11. The lower part of Foziling group which named Xiangyunzhai Formation is a set of metamorphic quartz sandstone whose protolith are sandstone and greywacke rock, and it has a tectonic setting of passive continental margin and a provenance of quartzite and sedimentary rocks which indicates the Yangtze(phile) geochemical features. However, the upper part of Foziling Group metamorphic rocks including Zhufoan Formation and Panjialing Formation mainly consists of a set of quartzmica schist, micaquartz schist, mica schist and minor quartz quartzite and its protolith are greywacke, sublitharenite, litharenite and shales. Its tectonic setting is continental island arc and active continental margin and its provenance are mainly quartzite sedimentary rocks and felsic igneous provenance. That shows the characteristics of North China Plateaffinitive. The above information suggests that Foziling Group has undergone the tectonic transformation from the passive continental margin of northern Yangtze to the active continental margin of southern margin of North China.

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    Geological and geochemical characteristics and genesis of magmatic rocks related to porphyry Mo deposits in the Beihuaiyang region.
    WANG Bei-Hua, ZHANG Fu-Dong, WANG Ping, XU Xiao-Chun, HAO Huo-Jin
    2016, 23(4): 46-62. 
    DOI: 10.13745/j.esf.2016.04.004

    Abstract ( 3353 )   PDF (2490KB) ( 8333 )  

    There are numerous porphyry molybdenum deposits located in the eastern Beihuaiyang area of QinlingDabie metallogenic belt, where the magmatism is closely related to mineralization. This study has investigated the intrusive rocks in the field which are closely related with porphyry molybdenum deposit, by using the method of wholerock major elements, trace elements and isotope geochemistry research, and discussed its petrogenesis. This research shows that the scale of metallogenetic rock body is small, and the lithology is porphyry granite, which is controlled by the fault structure in northeast and northwest. The chemical composition of rocks is characterized by high silicon, and potassium alkali rich, belonged to highK calcalkaineshoshonitic series, metaluminousperaluminous rocks. Trace and rare earth elements have similar characteristics and show features of crustal sources. Sr Nd Pb Hf isotope geochemical characteristics show that those matallogenic granitic magma has the same sources with Dabie Cretaceous granites. They both originated from Dabie granitic gneiss and TTG like magmatic rocks of the north Yangtze Block in the Neoproterozoic, and interfused some ancient crustal materials from palaeoproterozoic Yangtze craton(such as Kongling complex). The lower crust delamination, asthenosphere upwelling and largescale crustal extension happened in the Cretaceous, the northern margin of Yangtze craton crust melted and provided the mainly diagenetic materials. Upwelling of mantle derived magma probably provided heat source with little materials. The igneous rocks associated with Mo Deposits in this region are similar to Eastern Qinling metallogenic belt, which belongs to deephypabyssal granitoids.

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    The structural characteristics of Qinling intra continental orogenic belt and its Choula(drawing out) tectonic orogenic model.
    YANG Zhi-Hua, CHAO Hui-Xia, TUN Xu, WANG Bei-Ying
    2016, 23(4): 63-71. 
    DOI: 10.13745/j.esf.2016.04.005

    Abstract ( 3694 )   PDF (1437KB) ( 8227 )  

    Qinling orogenic belt is a famous orogenic belt in central China, and it is also a typical intra continental orogenic belt of continental tectonics. This type of orogenic belt did not undergo subduction of ocean crust to form such orogenic belt with main suture zone. It is not the collision orogenic belt that formed by the interaction between North China plate and Yangtz plate, and also not socalled composite orogenic belt. According to the composition, structural characteristics of different depth, crossbridge structure, structural style in the transformation of basin and mountain, the structural characteristics of Shangxian Danfeng tectonic zone and Mianxian Lueyang tectonic zone as well as the distinct north south direction structures in the central orogenic system (Qinling), the non plate features of these characteristics are discussed. On the basis of above discussion, the thrust Choula(or Choula) tectonic model for the formation of Qinling intra continental orogenic belt is built.

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    The structural deformation and tectonic evolution of intra continental orogeny in South Qinling orogen: Structural deformation analysis of the northern part of ShiquanHanyin belt in the late IndosinianYanshanian period.
    YANG Xin-Ke, HAN Ke, TUN Xu, WANG Bei-Ying, WANG Xin
    2016, 23(4): 72-80. 
    DOI: 10.13745/j.esf.2016.04.006

    Abstract ( 3462 )   PDF (1762KB) ( 8407 )  

    Intra continental orogeny has recorded a complex geological process. The research area, Ann Kang ShiquanHanyinXunyang belt, belongs to South Qinling orogen, and lies on the convergence parts of South Qinling intra continental compound orogen and the northern Yangtze plate. And there develops the early Paleozoic deformed metamorphic rock sheets of the Silurian system, which mainly is overthrust structure and multilevel ductile slip overthrust rock sheet. There widely produces new multistage foliations that can be classified into 3 stages since the Indosinian period; the foliation replacement shows distinctly, and S2 foliations replacing S1 foliations appears dominantly in the covering stratum area. Considering the following facts that the multistage structural deformation, the granite invasion into cap rock, the magma diapirstretch and heat dome rising of the basement, the thermal metamorphism with the late granite veins and high temperature mineral pairs that consist of secondary enlargement biotite porphyroblasts and garnet phenocrysts, the wide development of many types of hydrothermal alteration, the differences between the temperature and pressure characteristics of the fluid inclusions in quartz veins that exist in different stage foliations, that the Ar Ar dating of biotites along the ductile shear deformation foliations is 161169 Ma in Shiquan area, that the ArAr dating of micas along the ductile shear deformation foliations is 178163 Ma in the northern part of Fenghuangshan dome etc., it is suggested that the research area has undergone at least the Indosinian and the Yanshanian, the two tectonic deformation periods. Particularly, S2 foliation roughly corresponds to Yanshanian period, it is typically an intra continental orogenic structural deformation. The characteristics of plastic flow in solid state and brittle ductile shear deformation are significant. Through the structurepetrography mapping, we conclude that the S2 foliations are predominant in the area, their strike is mainly to the northwest; most of the new minerals and rocks are distributed along the S2 foliation, those suggest that Yanshanian period have a close relation to intra continental orogeny. The brittle ductile shear zones can emerge in the intense portion of structure deformation. The late IndosinianYanshanian period has been mainly presented by the combination of folds+S2+3 foliations+overthrust faults, the Cenozoic has been shown by the fault blocks with different degree in strike slip and uplift. The evolution of intra continental orogeny can be divided into three substages: (1)the collapse stage in the late Indosinian early Yanshanian period (T3J1+2); (2)the extrusion overthrust stage in the midlate Yanshanian period (J3K2); (3)the block uplifting and transformation stage in the Himalayan period. Intra continental tectonic convergence and strikeslip induced the condensation of tectonic thermal power in the upper crust, and formed the FenghuangshanNiushan magmaheat dome, leading to the partial melting of crust and the invasion of granite veins. The southern part, Annkang fault belt and the northern part, Ning Shann fault belt has undergone dextral strikneslip deformation and sinistral strike slip deformation respectively in Yanshanian period, which formed the more distinct east extrusion slip shear deformation in the study area, showing that the strikeslip of intra continental orogeny cannot be neglected.

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    Geological characteristics, ore forming ages and geological significance of DonggouJinlongshan gold deposit, South Qinling belt.
    LIU Yun-Hua, LI Zhen, ZHOU Su, HAN Yi-Xiao
    2016, 23(4): 81-93. 
    DOI: 10.13745/j.esf.2016.04.007

    Abstract ( 3557 )   PDF (2387KB) ( 8391 )  

    DonggouJinlongshan gold deposit located in flysch folded thrust belt brachyanticline in southern Qinling orogen is considered to be a typical Carlin type gold deposit and its metallogenic epoch yet to be determined. The regional tectonic system analysis showed that the brachyanticline is a dome structure which was formed by the superposition of east west closed dome and north east broad top anticline; the mineralization was mainly controlled by the late north east brittle structure and eastwest heterolithic facies unconformity interface. The geochemistry result of regional exploration shows that the anomalies of Au, As, and Sb register better, and that the anomalies distribute along northeast in beaded presentation and register obviously with the dome structure and the annular structure of remote sensing interpretation. The 40Ar/39Ar plateau age of sericite is 142.34±0.83 Ma, and the isochron age is 141.6±2.8 Ma, which shows that the mineralization happened in the early stage of the Late Mesozoic. The formation of pyrite has the characteristics of three periods; the auriferous pyrite has a symbiotic relationship with arsenopyrite and stibnite. Combining with regional date that the mineralization has a relationship with deep buried rock, and the deposit type is a remote epithermal deposit which is related to the deep hydrothermal fluid after the magmatic stage; the mineralization occurred in the squeezeextended transition period at 141142 Ma in the early Late Mesozoic; it suggests that the decompression and warming environment at the squeeze extended transition period is the most favorable metallogenic geodynamic background.

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    Origin of the breccia and metallogenic geological background of Mayuan Pb Zn deposit.
    HAN Yi-Xiao, LIU Yun-Hua, LIU Chu-Wen, LEI Mo-Sha, LI Zhen, LI Yun-Chao, LI Xin
    2016, 23(4): 94-101. 
    DOI: 10.13745/j.esf.2016.04.008

    Abstract ( 3401 )   PDF (1721KB) ( 8382 )  

    Mayuan PbZn deposit is a large PbZn deposit discovered in the South Dabashan intracontinental orogenic belt of the northern Yangtze plate recent years in China. According to the research of orefield structure, the mineralization was controlled by interlayer fracture zones of Sinian Dengying dolomite formation. Because of the large number of breccias at the bending of the tight folds in fracture zone, and the interstratified shearing glide fault zone near the footwall, it is suggested that the orecontrolling structure is a kind of faultfold occurring during the low angle thrustnapping procedure and the associated breccia. When mineral filled in the gap between the dolomite breccias of fracture zones, the miarolitic structure and comb structure of ore grew without destruction in the late period, which demonstrated that the deposit was formed during the structural forming stage. At the same time, we have got ReOs isotopic dating from the late mineralization asphalt with an isochron age of 126±8 Ma. Considering the tectonic setting, we believe that the deposit was formed in the middlelate Jurassic. The orecontrolling tectonic breccias are the product of the low angle thrustnapping structural effect.

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    Research on the geological characteristics of the Miaoya REE deposit, Hubei Province.
    CHAO Hui-Xia, SU Sheng-Rui, YANG Xin-Ke
    2016, 23(4): 102-108. 
    DOI: 10.13745/j.esf.2016.04.009

    Abstract ( 3466 )   PDF (1326KB) ( 8338 )  

    Miaoya REE deposit, located in the transitional zone between northeast margin of Northern Daba Mountains and western margin of Wudang uplift, is an oversize Niobium REE deposit associated with syenite carbonatite complexes. The time attribute and structure attribute of Wudang uplift that contains acid volcanic rocks as the main body are the most important basic problems, and the formation of Miaoya REE deposit has a close relationship with them. Miaoya complex is distributed along the fracture structure fragile zone between Yaolinghe group and Meiziya group of the Lower Silurian. NW and NWW faults and folds in the ore area were developed, which provided convenient channels and positioning space for the carbonate rock magma from the mantle to the shallow crust, and had certain control effect on the distribution of niobium, REE ore. From north to south, the syenitecarbonatite complexes consist of three facies belts: edge phase, transition phase and center phase. The wall rock alteration of the complexes has many types such as carbonatization. sericitization, biotitization, albitization and flouritization. Combined with regional geological background and geological characteristics of the deposit, the authors suggest that the carbonate rocks formed after the syenite, has a close relation with the syenite magma, and think that the mineralization material may have come from syenite magmas intrusion, then underwent gas water hydrothermal metasomatism after magmatism period, that is, all kinds of carbonatization alteration impelled niobium and rare earth elements to be enriched and precipitated. Before and after the complexes formation, the complexes were obviously controlled by the tectonic action; the early formed shrinkage cracks in the rock and structural fractured zone created favorable condition for the gaswater hydrothermal metasomatism at the later stage; and the mineralization mostly emplaced in the mylonite of Yaolinghe group. Miaoya REE deposit was produced by the coupling of the syenitecarbonatite that was formed by volcanic eruptions and the Sinian Paleozoic lithostratigraphy during the process of thrustnapping of the syenitecarbonatite with the Sinian Paleozoic lithostratigraphy.

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    Composition and tectonic evolution of Precambrian basement in South China and their control in diagenesis and mineralization.
    SHANG Jia-Fu, DAI Ku-Qian
    2016, 23(4): 109-128. 
    DOI: 10.13745/j.esf.2016.04.010

    Abstract ( 3523 )   PDF (3089KB) ( 8453 )  

    Based on the comprehensive analysis of the regional geological data, combining with the new geo age data, this paper divides the basement rock series into three classes and five layers: the Late ArchaeanEarly Proterozoic crystalline basement (D1); the Mesoproterozoic metamorphosed basement (D2); folded basement of the Neoproterozoic Qingbaikou system (D3A); the Neoproterozoic Qingbaikou systemthe Middle and Lower Devonian series (D3B), the Neoproterozoic Qingbaikou systemthe Middle and Lower Triassic series (D3C), and several tectonic units were divided, i.e., QinlingDabieSulu, Jiangnan, Nanhua, WuyiYuankai orogen and Kangdian multiple orogen from the north to the south. This paper expounds the evolution of the South China Block, which is consistent with the process of the super continent (Columbia in 1800 Ma, Rodinia in 1000 Ma and Pangea in 250 Ma), separating and convergence. This paper proposes that inland orogen has always undergone multistage tectonic movements, including cracking into a basin, extensional detachment, compressive squeezing and thermal uplift to form mountains. The forming geodynamic source may be provided by the extensional detachmentslip shear process within the lithosphere and different layers of crust caused by “mantle differential circulation”, under the prerequisite geodynamic setting of the differential rotation between several earths spheres. And then this paper summarizes the new tectonic framework in the MesoCenozoic, especially for south China caused by the Yanshan movement, explains widespread and direction of the distribution of volcanic magmatic activity, age migration, lithologic zonality and regularity of intrusion. Obviously it is not associated with the “East Asian multidirection convergence” and the westward subduction of the Pacific plate. This paper also classifies the main metal mineral deposits in south China into syngenetic, endogenic and superimposed mineral deposit, initially concludes the type, formation condition and regularities of distribution of these deposits, and finally gives some suggestions for the further exploration based on the control of rock and orecontrolling characteristics.

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    The structural composite metallogenic characteristics of Hubei Anhui Jiangxi giant ore concentration area.
    YANG Meng-Gui, XU Mei-Gui, HU Jing-Hua, WANG Guang-Hui, CHU Beng-Dun
    2016, 23(4): 129-136. 
    DOI: 10.13745/j.esf.2016.04.011

    Abstract ( 3340 )   PDF (1567KB) ( 8173 )  

    Through a comprehensive research, the authors put forward that the adjoining areas among Hubei, Anhui and Jiangxi provinces located in the eastern part of the Yangtze reversed S shaped structure in the Huanan Ocean tectonic domain were compounded with the clusters of Tancheng Lujiang fault zone of the Neocathaysian structural system during the Yanshanian period, and thus formed a giant endogenetic ore concentration area accumulated by a huge amount of metals. Therefore, it is called as the E Wan Gan giant ore concentration area, and the polymetals such as W, Cu, Au, Ag, U and Te occupy an important position in China. The research expounded the location and the continental margin arc basin system of Huanan Ocean of the Jinning period, and further explained the geological evolution, the tectonic framework and the mineralization from the Huanan Ocean of the Jinning period and the Yangtze Caledonian South China rift system to VariscanIndosinian epeiric sea since the MesoNeoproterozoic. The paper focuses on discussing the tectonic activity mode, the tectonic composite rock  and ore controlling characteristics of the Yanshannian intracontinental active orogenesis and metallogenetic magmatic explosion. Furthermore, the framework of Yanshannian giant ore concentration area and its spatial distribution of metallogenic belt, metallogenic subbelt, and major ore concentration area and ore field were preliminarily established. On the basis of the research, it is indicated that the geological settings of the Huanan Ocean of Jinning period and its continental marginal arcbasin is the favorable metallogenic foundation, while the firestorm of the multisource metallogenic magma and metallogenic fluids resulting from the Yanshanian intracontinental active orogenesis triggered by the intensive interaction between the Eurasian Plate and the PalaeoPacific Plate is the source of the largescale mineralization; meanwhile, the compounding between the two large structural domains and systems is the cause of the formation of giant ore concentration area.

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    Late Mesozoic multistage structural deformations feature in the adjacent region among Anhui, Zhejiang, and Jiangxi Provinces.
    JIANG Lai-Li, HU Shao-Ji, SHU Jiang, HUANG De-Zhi, WANG De-En
    2016, 23(4): 137-147. 
    DOI: 10.13745/j.esf.2016.04.012

    Abstract ( 3487 )   PDF (2308KB) ( 8324 )  

    Five periods of structural deformations in the Late Mesozoic era have been identified by systematic field investigation and structural analyses. The first one is the NEE trending thrust structure, which took place from the end of the Middle Jurassic to the beginning of the Early Cretaceous, approximately 160150 Ma. The second one is characterized by the highangel normal fault and the NNE trending leftlaterastrikeslipfault which formed at the beginning of the Early Cretaceous, approximately 150135 Ma. The third one is the NEE trending leftlateral strikeslip faults, which formed at the late Early Cretaceous, approximately 125120 Ma. The forth one is the NENEE trending rightlateral strikeslip faults formed at the end of the Early Cretaceous, approximately 100 Ma. The last main structural deformation is the top to the NWW thrust with an NNE striking, which formed at the early Late Cretaceous after 75 Ma. The multistage deformations are associated with the latest collision of the North China and the South China plate, and with the different directional subduction of the Pacific plate towards the EuroAsian plate at different stages, and even with the eastward remote extrusion effect of the collision between Indian plate and EuroAsian plate.

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    Structural analysis of Jiulongnao orefield in Nanling area: A case study on Taoxikeng tungsten deposit.
    LIU Zhan-Qiang, LIU Shan-Bao, LIANG Ting, WANG De-Gong, FEI Rong-Fu, LIANG Li-Jie, ZHANG Shu-De
    2016, 23(4): 148-165. 
    DOI: 10.13745/j.esf.2016.04.013

    Abstract ( 3354 )   PDF (3318KB) ( 8268 )  

    Taoxikeng tungsten deposit of Jiulongnao orefield in Nanling area is a typical quartzveintype wolframite deposit, and was formed both by the limits of faults and the granites in the south area of Jiangxi Province. In order to do structural analysis of the deposit, eight middletunnels mapping and nearground or hole drillings were completed, by which the geometry and structural and constructional characteristics of orebearing quartz veins, vein group, ore body and ore bearing granites were measured in detail, as well as collected statistical data of occurrences of ore veins and orerelated faults. The quartz vein orebodies existed in long straight plates with pinch out ends, and arranged in sinistral diagonal pattern, and the vein groups in different trend were crossed each other in diamond stockwork shapes. The ore bearing granite is a steplike rectangular block emplaced by stoping and dyke spreading intruded from NE to NW. The deposit and orebearing granite is of multiperiod in metallogeny and was formed by faults in a predominant factor. Thus the paper established a comprehensively structural and magmatic metallogenic model. That is, the conjugate fault grid system was induced by regional geological stress firstly; the granite upwelled and emplaced in diamonds cut by the faults and filled with greisen and orebearing quartz veins secondly; thirdly, reaction of regional tectonic events triggered breaks in wall rock and granite that induced another magma intrusion with ore and greisen veins, such as inner and outer belts of orebearing quartz veins. Although there were some slight displacements in the veins, the whole distribution was unchanged.

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    Element evolution of the planet earth and the relative movement of the earth interior: Rediscuss on the new global geodynamic theory about the development and evolution of tectonics in China.
    YANG Zhi-Hua, CHAO Hui-Xia, TUN Xu, SU Sheng-Rui, YANG Jun-Ru, YANG Ru-Jun
    2016, 23(4): 166-182. 
    DOI: 10.13745/j.esf.2016.04.014

    Abstract ( 3323 )   PDF (2895KB) ( 8289 )  

    On the basis of mass energy interchange in the Theory of Relativity, timespace bending, relative speed (twin effect), worms hole principle, some strange principles and the uncertain principle of quantum mechanics, as well as multiple historical thought, this paper has expounded the fact in an allround way about the essential feature and development of Qinling Mountains and the geotectonics of China. From the mass energy law, it is proposed that the formation of composition and the three layers of the earth, i.e., core, mantle and crust, were realized progressively by the burning stage up to the nuclear element. According to the order of nuclear burning, composition of the earth was formed as follows: the acid rocks with little atomic number were firstly formed, then, mafic ultrabasic to basic rocks with large atomic number were formed. The enormous energy produced in the course of nuclear element transformation is the only motive force source for geotectonic development and evolution. Its structure characteristic is the result of space time crooking during the process of highenergy and highspeed movement. The evolution of structural state determined by DNA and RNA has played a decisive role in the all birth and death of living things. Biological evolution is created by the earth itself using multidimensional timespace bending by prime number law. From the multiple historical thought and uncertain principle, this paper expounds the development stage, evolution as well as the randomness and probability for the production of events, composition and structures. Proceeding from the universality of space time crooking, three first grade tectonic units may be set up within the territory of China: QinghaiTibet Plateau, Siberia and southwest Pacific Ocean vortex throw outthermonuclear reaction. From the twin effects in the relative speed and worm holes principle, the orogenic zones in Chinas mainland may be a nuclearturned geologica1 body produced by highenergy and highspeed plasmaparticle flow fluid, which was drawn from deep part to top layer of the earth and then combined with the geological bodies on the earths surface for a long time. There are not any kinds of the Jinning, Caledonian, Cathanian, Yindonisan, Yanshan, and Himalayan orogenic zones. The drawingthrust rock slice structure is the main form for the formation of organic zone, also, it is an important movement way of lithosphere. Lastly, more than 10 difficult problems concerning with mineralization and biological evolution in geology are discussed, and the important function of earth mass limit value in the earth and biological evolution was put forward. In an allround way expounding the fact of the earth development and geotectonic tectonic evolution of China, it is thought that the vortex thermonuclear reaction, i.e., the new global dynamics theory, is a king of the limitless space of the earth.

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    Tectonic fluid and its formation conditions of Dabashan intra continent orogenic belt.
    QIN Xiao-Li, LI Rong-Xi, DONG Shu-Wen, LIU Hai-Jing
    2016, 23(4): 183-189. 
    DOI: 10.13745/j.esf.2016.04.015

    Abstract ( 3323 )   PDF (1142KB) ( 8282 )  

    The tectonic veins, as the field crop markers of tectonic fluid, record the source, environment and dynamic characteristics of geo fluid related to tectonic movement. Three periods of calcite veins (V1, V2 and V3) related to pre tectonics, syn tectonics and posttectonics respectively were identified in the Dabashan foreland. The formation environment conditions and source of fluid represented by V3 veins and developed within fractures under stretching environment were studied based on field survey and measurement of the occurrence of V3 veins together with the statistic and geometric features and wall rock mechanical properties of V3 veins,as well as the analysis of paleostress and isotope geochemistry of V3 veins. It is indicated that V3 veins are trending mainly in NE SW with steep dip almost upright. The directions of principal stress axes of σ1, σ2 and σ3are 67°∠76°, 200°∠13° and 293°∠10°, respectively. The paleostress field of V3 veins is of NW SE tension. The relationship of fluid pressure of V3 veins with principal stress axes is pf<σ2<σ1. Fluid overpressure is about 92167 MPa and the maximum depth is 1.87.2 km. Results of δ13C δ18O analysis show that V3 calcite veins formed from the decarbonization of carbonate of wall rocks. δDδ18O isotope of fluid inclusions contained in V3 calcite veins indicated that the water was mostly metamorphic water formed within basin and migrated to shallow place and mixed with surface water. Because abnormal high pressure fluid existed widely in Dabashan foreland, deep fluid with abnormal high pressure broke through the wall rocks and migrated along fractures towards shallow place and mixed with surface water to precipitate to form V3 veins under extensional tectonics in the Cretaceous Paleogene.

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    Intracontinental “lagged arc volcanic rocks” and its geological significance: Evidence from early Permian lagged arc magmatism in northern Urho area of Western Junggar.
    LI Yong-Jun, XU Qian, YANG Gao-Hua, CHAO Wen-Di, LIU Jia
    2016, 23(4): 190-199. 
    DOI: 10.13745/j.esf.2016.04.016

    Abstract ( 3422 )   PDF (1864KB) ( 8289 )  

     The “Lagged arc volcanic rocks” distributed in Urho area in the south of Hala’alat mountain of West Junggar. It is composed of Urho dyke swarms and Baiyanghe basalt, which constitute a complete continental volcanic apparatus and is angular unconformably overlying on the Jiamuhe molasse formation of Lower Permian system. The dyke swarms are composed of diabase, diabase porphyrite and gabbrodiorite. The LA ICP MS zircon U Pb ages of them are 283.6±2 Ma (MSWD=0.57, 95% conf.), 286.3±4.0 Ma (MSWD=0.32, 95% conf.) and 286.5±5.6 Ma (MSWD=0.3, 95% conf.). The LA ICP MS zircon U Pb age of Baiyanghe basalt is 283.7±3.1 Ma (MSWD=0.45, 95% conf.). All of these are in the late stage of the Early Permian. Urho dyke swarms and Baiyanghe basalt both have similar geochemical properties which are related to subduction of island arc, showing the features of middlelow K calcalkaline basalt to andesite series and enrichment of LREE. The anomaly of δEu is not obvious. All samples are characterized by the enrichment of LILE (K, Ba, Sr), the depletion of HFSE (Nb, Ta, Zr, Hf), positive εNd(t) values and relatively low initial Sr isotopic ratios, indicating that the source of the volcanic rocks is the enriched mantle. “Lagged arc volcanic rocks” occurred after the closure of ocean basin and the disappearance of trench arc basin system in surface, and later than postorogenic sedimentary record, suggesting that the final completion of the subduction in Western Junggar was in the late Early Permian. The outcrops of “lagged arc volcanic rocks” distributed along a belt, which may be the joint position of Siberia plate and TarimTianshan plate.

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    New exploration of geotectonic characteristics of Hainan Island.
    CHAO Hui-Xia, HAN Xiao-Hui, YANG Zhi-Hua, TUN Xu, LV Yan
    2016, 23(4): 200-211. 
    DOI: 10.13745/j.esf.2016.04.017

    Abstract ( 3314 )   PDF (2197KB) ( 8017 )  

    Today there are such understandings as geosynclineplatform theory, diwa theory, islandarc theory and plate tectonics theory for Hainan Island tectonics. All these views, including mobilism of plate tectonics, are established on the basis of fixism of vertical movement, which believe that strata and rocks, especially granite was formed in situ, and accordingly established the multi stage and multi cycle of tectonic cycles or a geosyncline, platform and platform activation (or diwa) stage of development and evolution history, which embodies the mutual transformation of the activity and stability of the progressive process. When we reanalyze the existing data by using the new global dynamics theory, Choula tectonics forming fold belt and the orogenic model theory to rethink the tectonics of Hainan Island, these views are questionable. Through the analysis, it is found that, firstly all the PreCretaceous strata of Hainan Island have the unclear top and the contact relationship is unknown, often showing the fault contact. The establishment of the rock stratum does not accord with the relevant regulations, it is not able to establish the stratigraphic column in unification of the island according to the time sequence; it is also not able to establish geological tectonic cycle and geotectonic development stage according to the time sequence and integration relationship. Secondly, the most popular rock of Hainan Island is composed of the gneissic granite, which is obviously different from the continental fold belts (orogenic belts) composed of sedimentary metamorphic rocks. The gneissic granite with migmatization actually belongs to Archean TTG suite, which is not the intrusive rock emplaced in the PreCretaceous strata, but the sheet tectonics drewthrusted and pushed over the surface. Thirdly,according to the contact relationships of Island lithostratigraphy, it can be divided into five rocksheet structure systems: autochthonous system, quasi autochthonous system and three foreign systems, and then, the structural units are partitioned accordingly. Fourthly, Hainan Island, belonging to the firstorder tectonic units is the Tibetan Plateau vortexthrowing outthermonuclear reaction tectonic system. The secondary tectonic unit is the South China Sea and Hainan Island vortex structure zone, and the thirdlevel tectonic unit is Hainan Island vortexshear structure and interior pillar structure. Fifthly, the combined effects of the pillar shaped uplift and hot spot of basic volcano rocks of South China Sea is the fundamental reason of Hainan Island’s outcropping above the sea surface, belonging to autochthonous system. Sixthly, different rocksheet structure systems layered and piled up above nuclear columnhot spot tectonics according to the drawing out tectonics, which is the basic characteristic of the tectonic framework of Hainan Island. And finally the geotectonic history of Hainan Island can only begin from the late Mesozoic.

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    Ore related geoanomaly sequences: Examples from the Middle Exploration Area of the Lalingzaohuo River, Qinghai Province.
    LUO Zhao-Hua, GUO Jing, WANG Bing-Zhang, I.V.Vikentyev , WANG Chao
    2016, 23(4): 212-225. 
    DOI: 10.13745/j.esf.2016.04.018

    Abstract ( 3784 )  

    One of the keys in exploration of metal resources is to find the geoanomalies matched to the geochemical and geophysical anomalies, and to relate the geoanomalies to the master orebody, step by step. In order to decipher such processes, a new concept is provided as the ore related geoanomaly sequence (ORGAS) which is further divided into the theoretical and the exploration sequences, based on the observations in the Middle Exploration Area of the Lalingzaohuo River, Qinghai Province(MEAL). The theoretical sequence is the record of a series of orerelated geological processes occurred in the mineral system in the specified spatial and temporal sequences, which can be deduced based on a metallogeny theory. The exploration sequence is constructed in the exploration practice, and follows the principles of anomaly notability and prospecting efficiency. The exploration sequence may or may not identical to the theoretical, but its construction has to follow principles of the theoretical sequence in order to quickly and economically evaluate the resource potential of the exploration object. The deduction of the theoretical sequence is based on a theory of metallogeny system, deciphering the events and the processes in the spatial and temporal structure of the mineral system and their causal relations, and constructing an ORGAS. According to the theory or transmagmatic fluid metallogeny, the evolution of a mineral system can be simply attributed to that the metalrich fluid is transferred from a magmatic intrusion to the places, far from the intrusion. In this process, the metalrich fluid may strongly interact with every trapping media, leaving the remarkable material records. Accordingly, it can be assumed that the features of the trapping media and strong interactions are known, hence the material records can be predicted, and the ORGAS can be constructed. In the exploration, a series of the orerelated geoanomaly (ORGA) and anomaly populations can be found simultaneously, and the first ORGA is generally not the anomaly related to the master orebody; the scenario of the ORGAS is more complex than that of theoretically deduced one. Therefore, the anomalies are required to be divided into direct, indirect and background in the exploration, and the indirect anomaly is required to be translated to the direct. At the same time, the anomalies are incorporated to anomaly populations on the basis of anomaly distribution pattern, constructing the exploration sequence. It is obvious that the exploration sequence is not following the theoretical sequence, because it follows the principles of the anomaly notability and the prospecting efficiency. However, in order to find the explicit prospecting variant, the explorers should continually use the theoretical sequences, enrich the theoretical sequences, and, finally, construct new theoretical sequences. According to the mentioned methodology, the ORGA discovered in the MEAL can be incorporated into two exploration sequences: (1) the batholith occurrence anomaly→the igneous texture anomaly→the mineralization pattern anomaly→the pegmatite anomaly; (2) the batholith occurrence anomaly→the skarn anomaly→the dike swarm anomaly (mineralized belt distribution anomaly) →the intrusion structure anomaly→the mineral generation anomaly. Based on the analysis of the ORGAS, the Taoge intrusion and the intrusion buried beneath the Hedong batholith are inferred to be the conduits of orebearing fluids. Accordingly, it is suggested that the two intrusions should be the targets of the next exploration program.

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    Genesis of magma mixing and mingling of Xiangjiananshan granite batholith in the eastern section of East Kunlun Orogen: Evidence from Mafic Microgranular Enclaves(MMEs).
    CHEN Guo-Chao, FEI Xian-Chi, LI Rui-Bao, LI Zuo-Chen, LIU Cheng-Jun
    2016, 23(4): 226-240. 
    DOI: 10.13745/j.esf.2016.04.019

    Abstract ( 3454 )   PDF (2688KB) ( 8351 )  

    East Kunlun Orogen is a natural site to study the magma mixing and mingling, where a lot of granitic magmatic rocks outcropped with widely developed mafic microgranular enclaves in it. Taking the Xiangjiananshan granitic batholith in eastern section of East Kunlun Orogen as the object, the paper has studied the field geological characteristics of mafic microgranular enclaves developed in the batholith, in order to research the magma mixing and mingling and the magma dynamics process. The enclaves have fine grained to medium coarse grained texture, and contain phenocrysts like plagioclase, amphibole, quartz, mafic minerals edged quartz, and K feldspar, which stretch across the host rocks and enclaves occasionally. The enclaves often contain back veins, and the contact boundaries between the enclaves and host rocks are sharp or transitional. The above characteristics suggest that the mafic microgranular enclaves are the products of magma mixing and mingling, in which an interchange of material have taken place in the processes. The textures of enclaves vary from fine grain to coarse grain, and dispersive to completely mixed, indicating that the proportions of magma mixing become bigger and the temperature differences between the two magmas become smaller. The temperature differences between the two magmas have a great influence on the formation of enclaves. Research on the morphology of enclaves shows that they have different stretch degrees, resulting from interactions among viscosity, temperature, flow rate, etc. The plastic deformation degree increases with the stretch degree of the enclaves. The enclaves have different longaxis directions, mainly divided into two categories, one with approximately directions representing the magma flow direction, one with no fixed direction or with several different directions at the same outcrop representing the magma partial stirring and convection. When injected into the acidic magma represented by the host rocks, the basic magma represented by the enclaves came into rotating and flowing, and partial stirring of the acidic magma may have occurred, which produced the directionalities of the minerals on the enclave edges and in the host rocks. The phenomena of enclave in enclave and different types of enclaves in the same outcrop indicate a multiple magma mixing and mingling. Field geological characteristics of mafic microgranular enclaves in Xiangjiananshan granitic batholith have provided important evidences for the magma mixing and mingling and the magma dynamics process.

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    The solidification process of Qingpi Village Miyi mafic intrusion, Sichuan.
    QIU Yi-Dan, LUO Zhao-Hua, YANG Zong-Feng, LI Hua-Jun, LI Jie, CHENG Jin-Hua, I.V.Vikentyev
    2016, 23(4): 241-254. 
    DOI: 10.13745/j.esf.2016.04.020

    Abstract ( 3520 )   PDF (2106KB) ( 8082 )  

    The distinction between ore bearing intrusions and non ore bearing intrusions is the basis for the understanding of the formation of magma type deposits, and it provides also the evidence for deep prospecting prediction. In this article, the author takes the Qingpi Village Miyi mafic intrusion, Sichuan as an example, using petrography and mineral composition profile and quantitative texture analysis to clarify the solidification process of non ore bearing intrusions, then compares it with ore bearing intrusions of Panzhihua to explain the difference in the formation process between them. Petrographic analysis shows that rock forming minerals of medium grain gabbro from Qingpi Village intrusions can be divided into 4 generations: ①coarse grained plagioclase→②medium grained plagioclase+clinopyxene→③biotite+Fe Ti oxide→④very coarse grained plagioclase, demonstrating the solidification process of the closed system. Adding up the mineral association: albite+clinopyxene+amphibole+apatite from the very coarse grained gabbro veins, we can divide the minerals of Qingpi Village intrusions into 5 generations and 4 crystal populations: channel crystal, chamber crystal, matrix crystal and fluid crystal. The mineral composition profiles indicate that the channel crystal and chamber crystal have the normal zoning, showing the feature of cooling crystallization of closed system, and the growth of the channel crystal is accompanied by the decompression effect; that the matrix crystal initially has the normal zoning and finally has the opposite zoning, demonstrating the aggregation and escape of residual fluids; and that the appearance of fluid crystal shows the phase separation and venting of super critical fluids. Quantitative texture analysis reveals the coarsening process in the later period of solidification, which is the important evidence for the solidification process of closed magma system, consistent with the petrographic and crystal composition profile analysis. In addition, the Fe Ti oxide content in Qingpi Village intrusion is only 4 Vol% which is unlikely to accumulate forming the mineralization. Compared with the Panzhihua intrusion, the solidification process of Qingpi Village intrusion is lack of the dissolution structure of previous existing crystals, which is considered as the result of influx of high temperature ore bearing fluid. Accordingly, this article proposes that whether there is the external orebearing fluid(transmagmatic fluid) input determines the capacity of oreproducing of mafic magma intrusions; that furthermore, it is considered that the fluid input leads to magmatic differentiation, instead of magmatic differentiation inducing the formation of ore bearing fluid.

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    Structural characteristics and geometric models of the Yasongdi Fault Belt, the Bachu Uplift.
    ZHENG Xiao-Li, HE Guang-Yu, TAO Ze-Wei
    2016, 23(4): 255-264. 
    DOI: 10.13745/j.esf.2016.04.021

    Abstract ( 3399 )   PDF (2014KB) ( 8229 )  

    In this study, based on the analysis of seismic sections we identified three stage development of thrust and fold structures and built up the geometric models of the Yasongdi and adjacent belts in the Bachu Uplift, Tarim Basin. Firstly, the NWW trending Bashituo Fault was formed after the Permian but prior to the Paleogene, which slipped along the Middle Cambrian gypsum salt layer.Then, the Selibuya Fault with a NNW strike characterized by basement involved structures was formed in the Late Miocene. Finally, the Yasongdi Faults in the shallow and deep domains were developed during the Pleistocene to Holocene with the same NW trends, however, slipped along the Paleogene and Middle Cambrian gypsum salt layers, respectively. In map view, the development of the Yasongdi faults is restricted by the extent of the Paleogene salt. Influenced by the rejuvenated Bashituo and Selibuya faults, the Yasongdi fault belt can be divided into three segments: the eastern segment is featured by the upper fault propagation fold and lower detachment fold; the central segment is mainly composed of the upper fault propagation fold, middle detachment fold, and lower basement involved structure; and the western segment consists of the upper detachment fold and lower fault bend fold. All the geometries of superposed folds described above have been reproduced by our numerical analog modeling.

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    Decomposition the detrital grain ages by Kernel Density Estimation and its applications: Determining the major tectonic events in the Songliao Basin, NE China.
    SONG Ying, ZHANG Dun-Xia, Andrei Stepashko, YUAN Mo-Meng, CONG Xu-Ri
    2016, 23(4): 265-276. 
    DOI: 10.13745/j.esf.2016.04.022

    Abstract ( 3481 )   PDF (1935KB) ( 8058 )  

    The thermochronology of detrital grains has quickly become a very popular technique for understanding some complicated geological processes, e.g. plate collision, orogeny and sedimentary provenance studies. Detrital single grains from well dated sedimentary formations contain different age components, serving as mineral tracers in sedimentary systems and record the sedimentforming processes. Therefore how to decompose and visualize the ages faithfully and extract possible geological information are keys to the understanding thermochronology result of detrital grains. Binned Frequency Estimation and Probability Density Estimation are two extensively using approaches. Unfortunately, both of them lack a firm theoretical basis and can produce inaccurate results when data quantity or quality is low. This paper introduces a statistical technique for analyzing isotope age, called Kernel Density Estimation (KDE), which involves the age data, but explicitly takes into account the analytical uncertainties by inherent adaptive bandwidth functions. Such adaptive functions vary the bandwidth according to the local density, avoiding the uncertainties from analytical errors and age abundance. Finally, we used the KDE to study two independent thermochronology date sets in northeast China: the zircon UPb ages of Phanerozoic granitoids in Great Xingan Range and the single grain fission track ages of detrital apatite in the Songliao Basin. The estimated age pattern coincides with the regional tectonics and tectonosedimentary records in the study area. It also gives more accurate chronological constraints to some major regional tectonic events. Thus, the KDE proves to be a valid statistical approach for geologic age decomposition.

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    Characteristics of shale organic matter thermal evolution in Paleogene Shahejie Formation in Jiyang depression.
    BO Ren-Fang, CHEN Mei-Ling, ZHANG Chao-Mo, CHEN Lu-Yin, YANG Bao-Gang
    2016, 23(4): 277-283. 
    DOI: 10.13745/j.esf.2016.04.023

    Abstract ( 3356 )   PDF (1101KB) ( 8070 )  

    Paleogene Shahejie Formation is investigated for its excellent shale oil potential in Jiyang depression, Bohai Bay Basin. The thickness of Shahejie Formation shale within the oil window reaches more than 1000 m and the characteristics of shale organic matter thermal evolution has attracted widespread interest. Based on the detailed statistics of the pyrolysis geochemical parameters for five exploration wells for shale oil, the analyses of original total organic carbon (TOCo) of a source rock, the convertible carbon (Cc), the oil in place from S1 and generation potential from S2 etc., the characteristics of the shale organic matter thermal evolution of Shahejie Formation has been studied, and the vitrinite reflectance kinetics of shale has also been discussed in this paper. The results suggest that Shahejie Formation shale(lower part of the 3rd and upper part of the 4th Member of Shahejie)is of particular exploration interest, which yields the maximum pyrolysis temperature (Tmax) values ranging from 423 ℃ to 450 ℃.The thermal maturity (Ro) values range from 0.45% to 0.94% with the average value of 0.73%, implying that it belongs to the mature oil window shale. Original total organic carbon (TOCo) values of a source rock of type II values range from 0.64% to 7.25%, and the average TOCo is 4.60%. Organic carbon converted to hydrocarbons is called convertible carbon (Cc), and its values range from 51% to 63%, with the average Cc value of 59%. The oil content of shale values range from 10×104 t/km2 to 75×104 t/km2, with average value of 39.67×104 t/km2. The hydrocarbon generating potential values range from 20×104 t/km2 to 465×104 t/km2, with average value of 293×104 t/km2. Pyrolysis production index (PI) (or S1/[S1+S2]) values range from 0.03 to 0.47. The comprehensive study reveals that the excellent source rocks of Shahejie Formation are concentrated in Dongying and Zhanhua sags, and the thermal maturity is significant for the generation and accumulation of shale oil. When the Ro values were at about 0.70%0.74% the expulsion of hydrocarbons began.

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    The discovery of microbial debris in the coarse clastic rock of the early Mesoproterozoic in Liaoning Province, China and its paleoenvironmental significance.
    XU Xiao-Hui, CHEN Jun, LIN Ling-Ling, FAN Tian-Qi
    2016, 23(4): 284-291. 
    DOI: 10.13745/j.esf.2016.04.024

    Abstract ( 3355 )   PDF (1772KB) ( 8140 )  

    The Changzhougou Formation in the Proterozoic is a set of clastic rock unconformably on the Archean granite gneiss. On the coarse clastic rock of the bidirectional cross bedding lying on the bottom of Changzhougou Formation in Xingcheng, Liaoning Province, we found a large number of sandy microbial particles, size of which is between 0.1 mm and 0.2 mm, giving priority to spherical shape, as well as square and ship type. This paper argues that the cause of these sandy microorganisms particles is that the microbial matground in the relatively hydrodynamically quiet supratidal flat or high tide mud flat was damaged by the storm and tsunami disaster events by intense tectonic movement and high frequency sea level movement in the early transgression movement at the beginning of the Mesoproterozoic erathem. Then it was transported to the strong hydrodynamic and bimodal crossbedding developed area of the tidal channel with the tide flow and deposited with detrital material; in the process of transportation, these particles damaged by the storm were rounded and sorted. At the same time, on the basis of the primary sedimentary structure of these microbes and characteristics of sedimentary of the development of the Changzhougou Formation, we identified the formation environment of the Changzhougou Formation as the barrier islandtidal flat sedimentological system.

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    Benthic foraminiferas implications on paleo environment variability in MD12-3432 in the northern South China Sea since MIS 11.
    LIANG Jing-Zhi, HUANG Bao-Qi, DONG Die-Ting, GU Wen-Bo, ZHOU Pan-Xi
    2016, 23(4): 292-300. 
    DOI: 10.13745/j.esf.2016.04.025

    Abstract ( 1934 )   PDF (1371KB) ( 2728 )  

    The South China Sea (SCS) is a typical marginal sea whose northern continental slope has a high sedimentation rate, which provides ideal material for research on sub orbital scale climate variability. In this study, samples from sediment core MD12-3432 (19°16.88′N,116°14.52′E, water depth 2125 m) retrieved from the lower northern continental slope, northern South China Sea, are selected as the major research material. By applying multiple paleo environmental poxies analysis, including benthic foraminifera abundance, coarse fraction percentage, specific environment indicators percentage and abundance as well as relevant results from previous studies, the paleoceanographic history of the northern South China Sea is reconstructed, with emphasis on the variability of surface primary productivity and bottom water dissolved oxygen content. Different from previous studies, the results indicate that from Marine Isotope Stage 11(MIS 11, approximately 400 ka B.P.) the primary productivity in the northern SCS is high in warm interglacial period and low in cold glacial period, and it is mainly influenced by the intensity of precipitation controlled by the East Asian Summer Monsoon. During MIS 7 and MIS 9, the rise in the abundance of a low productivity and high dissolved oxygen indicator, the epifaunal Cibicidoides wuellerstorfi, coincides with high productivity indicators records. This inconsistency implies a possible intrusion of oxygenenriched bottom water in both warm time periods.

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    Paleo environment change and river channel infilling since late MIS 3 recorded by drilling core QX01 from the coastal lowland of Bohai Bay.
    WANG Fu, LI Jian-Fen, CHEN Yong-Qing, WANG Hong, FANG Jing
    2016, 23(4): 301-309. 
    DOI: 10.13745/j.esf.2016.04.026

    Abstract ( 1895 )   PDF (1709KB) ( 2960 )  

    We used an AMS 14C and OSL dated core (QX01) from the coastal lowland of Bohai Bay to decipher the late Pleistocene paleo environment change and river channel infilling. Sedimentary facies, grain size, large amplitude changes in benthic foraminifers assemblage and diatom assemblage composition indicate that the major environmental changes occurred during the last 40000 years in the study area. The results show that 6 sedimentary stages were identified, which is (1) 3029.72 m: fluvial deposition; (2) 29.7229.4 m: transgression deposition, >43.5 ka; (3) 29.417.7 m: sandy sediments, river channel filling, ~37.929.7 ka; (4) 17.713.2 m: sediments finning from sand to clay, ~29.78 ka, the environments from river channel infilling to swamp; (5) 135 m: 84 ka, Holocene transgression deposits, the environments from fresh water swamp, to brackish swamp or salt mash, to shallow sea, to salt marsh, most strongest marine influence happened during 60005750 cal BP, then retreat; (6) 50 m: since 1.7 ka, the environment was controlled by river, and it is flood plain deposits during this period. The sedimentary changes were correlated with sea level change very well. During MIS 4 or 6, the sea level was relatively lower, the river cut down and river channel formed, then the river channel was infilling during 37.929.7 ka of MIS 3, when the sea level was relatively higher, the height of the river channel were infilled from -24.2 m to -11.8 m of Huanghai 85 highness. Then the last glacial maximum came, the sea water retreated out of Bohai Sea and the study area was swamp or shallow lake; the sedimentation stopped or at a very low level till the early Holocene, 8 ka. With the end of the last glacial maximum, the sea water came back again during 84 ka, represented by fresh swamp, salt marsh, and shallow sea deposits. Then the deposition stopped again, till 1.7 ka, with the role of the river, the environments became floodplain deposits. Moreover, two sedimentary break were identified, which is the break during last glacial of low sea level, and the break during 41.7 ka, when the marine influence finished or sea water retreated from the study area, but the role of the river had not started.

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    Change of the lakes in Tibetan Plateau and its response to climate in the past forty years.
    YAN Li-Juan, ZHENG Mian-Beng, WEI Le-Jun
    2016, 23(4): 310-323. 
    DOI: 10.13745/j.esf.2016.04.027

    Abstract ( 3507 )   PDF (2295KB) ( 7944 )  

    The levels and surface areas of lakes are indicators of climate change and climate variability. The authors extracted surface extent of all lakes in the Tibetan Plateau from Landsat remote sensing images of the 1970s, of the 1990s, around 2000 and 2010 based on RS and GIS and developed the lake spatial database in combination with on the spot investigations to a few representative lakes. The results show that the total surface area of lakes, each of which has an area larger than 0.5 km2, increased by 13.42% during the period of the 1970s to the 1990s, increased by 4.86% during the period of the 1990s to around 2000, and increased by 13.04% from 2000 to around 2010. It showed that lakes in the study area keep the expanding trend in the past forty years. We found that the climate of the Tibetan Plateau changed from warm dry to warm wet gradually characterized by increasing temperature, precipitation, and dropping evaporation through the meteorological data. Meanwhile, all lakes, each of which has an area larger than 10 km2, suitable for the surface area changes analysis were selected to compare the dynamic changes one by one, and the division of these lakes into expansion area and atrophy area was made according to dynamic changes. The variations of the lakes differ from area to area in different periods, and the response to climate is strong. In practical terms, between the 1970s and the 1990s, lakes in north and middle Tibet, southern Tibet, Qinghai Qiangtang Basin and east Qinghai were shrunk whereas lakes in other places tended to expand. From the 1990s to 2000, lakes in north Qinghai were shrunk. From 2000 to 2010, most lakes in the study area except southern Tibet expanded. Different climate parameters can produce different effects in different areas: temperature mainly affects lakes which rely on glacier melt water runoff for supply, such as Siling Lake and Chibuzhang lake; precipitation mainly influences lakes recharged by precipitation and surface runoff, such as Qinghai Qiangtang Basin; evaporation brings about water loss of all lakes, which influences areas with evaporation effect caused by raising temperature surpassing the increase in precipitation and runoff, such as Yamdrok Lake. Tectonic activities play an important role in the evolvement of lakes in long time scales, controlling the big pattern. While the climate shapes lakes more directly in short time scales. Besides, The dynamic changes of the lakes also can be influenced by other factors, such as glaciers, human activities, lake basin shape, open or closed systems and catchments.

     

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