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    20 March 2013, Volume 19 Issue 1
    Relationship Between Caledonian Granitoids and Large-scale
    Mineralization in South China
    HUA Renmin, ZHANG Wenlan, CHEN Peirong, ZHAI Wei, LI Guanglai
    2013, 19(1):  1. 
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    The Caledonian granites take the second importance among the multi-aged granitoids in so-called South China Large
    Granite Province. However, the pervious studies show less concern on the metallogenic aspects of Caledonian granites. Some early studies considered no important mineralization related to Caledonian granites. Based on some newly discovered granitic intrusionsof Caledonian ages, together with the synthetic assessment of related literature, the present paper reviews the general character of Caledonian granites and discusses the relationship between Caledonian granites and large scale rare metal metallogeneses in South China. Although the large-scale rare metal mineralization mainly took place in the Yanshanian Period of Late Jurassic Era,Caledonian granitoids of mostly Silurian Era made great positive effects. Some well-evolved Caledonian granites, such as those in Penggongmiao of southeastern Hunan, Niutangjie of northern Guangxi, Guiling of northeastern Guangxi, and Qingjie of Youjiang area, can cause W, Mo and Sn mineralization. Some others might serve as rare metal supply for mineralization associated with late-staged granites, such as Shilei of southern Jiangxi and Meiziwo of northern Guangdong. At Yijiang of southern Hunan, the weathering products of Caledonian quartz diorite form a unique REE-Sc deposit. The most important significance, however, is that the Caledonian Orogeny started the intra-continental crust evolution of South China. The Caledonian granitoids resulted mainly by melting of crust materials, instead of adding of mantle material. The following tectonic episodes such as Variscan, Indo-sinian, and Yanshanian, together with the accompanying granitic magmatism, promoted the forward evolution of crust. As a result, the crust of South China became highly matured, which is indicated by high enrichment of felsic components and lithophile rare metals, and finally yielded the largest rare metal mineralization in the world.

    Discussion on Hierarchical Scheme of Architectural Units in Clastic Deposits
    WU Shenghe, JI Youliang, YUE Dali, YIN Senlin
    2013, 19(1):  12. 
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    The hierarchical structure of clastic deposits is an intrinsic feature of a complex geologic body. As such, the clastic
    deposits are studied in a hierarchical style and divided into different architectural units. A comprehensive architectural unit
    hierarchical scheme in inverse order for clastic deposits is proposed through integration of the existing lithosome architecture
    hierarchy scheme and the sequential architecture hierarchy scheme based on the join point of maximum autocyclicity and
    minimum allocyclicity according to architectural scale and its relation. This scheme is compared with the present sedimentary
    facies classification system in China. In the proposed scheme, a continental basin is divided into twelve architectural units
    according to their different orders. Among them, the first to sixth units correspond to sequential architectures, the seventh to
    ninth units are facies architectures, and tenth to twelfth units are in an order of bedding architecture. The proposed division
    scheme will remove the hinder coursed by variety division schemes that exist in exploration and development research area. It
    will benefit to promote an integration of subsurface geological study. In the proposed scheme, the architecture units in exploration
    stage belong to first to fourth order, while the architecture units are grouped as fifth to ninth order in the development stage. The
    present sedimentary facies hierarchical system used in China is not an architectural hierarchy system. Thus, the facies hierarchy
    is not uniformed among variety sedimentary environment. The microfacies in present facies hierarchical system have significance
    hierarchical meaning and could be used as an architecture unit, but the subfacies has no meaning of architecture units.

    Sedimentary Characteristics and Evolution of Shallow-water Delta of
    the Lower Cretaceous Fuyu Reservoir in the Yushulin Oilfield, Songliao Basin
    LI Yang, ZHU Xiaomin, SONG Yingqi, LIU Fen, LI Chao
    2013, 19(1):  23. 
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    The Yushulin Oilfield, located in the Sanzhao Depression of the Songliao Basin, developed large shallow-water deltas at
    the time when the Fuyu Reservoir deposited within the Member 4 of the Lower Cretaceous Quantou Formation. Based on 12 well
    cores and 2268 well loggings, by ways of single-well facies, logging facies, connecting-wells and plane sedimentary microfacies,
    well-developed shallow deltas were recognized in the study area in which can be further subdivided into delta plain, internal front,
    external front, predelta, and delta plain subfacies. Main sedimentary microfacies are plain distributary channel and internal front
    subaqueous distributary channel. These two types of channelized sandstone bodies interlaced into a network. During the early
    stage of the Member 3 of the Fuyu Reservoir, the studied area was dominated by shallow-water delta internal front subfacies which
    was sourced from north only. Later, the delta prograded towards south, and the studied area changed into delta plain subfacies. At
    the time of the third layer in the Member 3 of the Fuyu Reservoir, source from south appeared and intersected with the northern
    source. This sedimentary condition continued to the latest stage of the first mewber of the Fuyu Reservoir FⅠ At the time of the
    third layer of the Member 1, both the northern and southern deltas retrograded due to the sudden rise of lake level. In the middle
    part of the studied area, delta internal front, external front, and predelta were developed in proper order.

    Distribution of clastic karst reservoirs of the Paleogene Dongying Formation in the Jidong Laoyemiao oil field
    JIN Zhenkui, YANG Youxing, DONG Chenchen, WANG Yan, HE Miao 
    2013, 19(1):  32. 
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    Carbonate karst reservoir is very common, but no reports on clastic karst reservoir. The clastic karst reservoirs have
    been discovered in the Paleogene Dongying Formation in the Jidong Laoyemiao oil field in this study. The distribution and control
    factors of the clastic karst reservoir are very similar to those of the carbonate karst reservoir. The sedimentary facies of sandstone
    reservoir of the Dongying Formation is delta. Within sandstone reservoir, calcareous cementation is widespread. Based on the core
    and log data analysis, sandstone karst reservoir developed in a zone of 150 m in thickness below an unconformity between the
    Neogene and Paleogene strata. The porosity of the sandstone karst reservoir is mainly produced by the dissolution of calcareous
    cements. We suggest that a zone below unconformity is favorable to reservoir development for calcareous sandstone.

    Origin of dolomitic reservoir rock in the Permian Fengcheng Formation in Wu-Xia area of the Junggar basin
    ZHU Shifa, ZHU Xiaomin, TAO Wenfang, LIU Shiqi, CHEN Hehe, ZHANG Yueqian
    2013, 19(1):  38. 
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    The dolomitic rocks of the Permian Fengcheng Formation are formed under special geologic conditions, and are
    important hydrocarbon reservoir rocks in Wu-Xia area in the Junggar Basin. Data of petrologic characteristics, SEM EDS and
    stable isotope composition indicate that dolomitizing host rocks are volcaniclassic rocks. Dolomitizing fluids probably came from
    brine from nearshore and shallow-water lake deposits in the Fengcheng Formation, which formed under arid climatic conditions,
    and from residual Mg-rich seawater from underlying Jiamuhe Formation and Carboniferous strata. Tuff has a significant content
    of plagioclase, in which anorthite and labradorite hydrolysis by CO2 can be couple with calcite precipitation. Later, Mg-rich brine
    percolate and replace calcite of the first stage to precipitate dolostones. The dolomitizing fluid has been driven by the thermal
    convection flow generated by volcanic eruption. At the same time, the overthrust of the Wu-Xia growth fault have speeded up the
    flow of deep Mg-rich water upwards, and induced the water to quickly penetrate and horizontally migrate in the strata. Fracture
    and fault play important role in controlling the formation of dolostone and the distribution of favorable reservoir.

    Early Permian volcanic lithology, lithofacies and their relations to reservoir in northwestern margin of the Junggar basin
    XIAN Benzhong, NIU Huapeng, ZHU Xiaomin, DONG Guodong, ZHU Shifa, AN Siqi
    2013, 19(1):  46. 
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    Early Permian volcanic rocks in northwestern margin of the Junggar Basin have different rock types and lithofacies.
    In this paper, data from core, thin sections and element chemistry were used to study volcanic lithology and their relations to
    reservoir quality. The Jiamuhe Formation is characterized by lava and volcanoclastic rocks, which are mainly basaltic andesites,
    andesites and quartz andesites. The lithology of volcanic rocks in the Fengcheng Formation are different in different areas. Lava
    including basaltic andesitoid and tephrite was the main type in Kebai area, while welded pyroclastic rock and volcaniclastic lava
    of rhyolite, pollenite and andesitoid are the main types in Wuxia area. The high-quality reservoir developed in eruptive breccias
    and lava such as andesite in the Jiamuhe Formation and in the Fengcheng Formation of the Kebai area, and in welded pyroclastic
    rock and breccias lava with stone bubbles in the Fengcheng Formation of the Wuxia area. Besides, same volcanic rock would
    have different reservoir quality because of different volcanic environments. In the studied area, although diagenesis was diverse

    in different parts, high-quality volcanic rock reservoir developed mainly in the upper effusive sub-facies, air fall, and pyroclastic
    subfacies in explosive facies. Effusive and explosive facies were common in the Jiamuhe Formation, while effusive facies and
    pyroclastic flow subfacies in explosive facies were the main facies in Fengcheng Formation of Kebai area and of Wuxia area,
    respectively. Therefore, distinct explorative targets should be chosen in different layers in different areas. Lithofacies was another
    important controlling factor for volcanic reservoir besides fracturing in fault zones and leaching under the regional unconformable
    surface.

    Main controlling factors of Putaohua oil reservoir in Yushulin oilfield, Songliao basin
    DING Xiujian, LIU Guangdi, LIU Chunlin, SUN Mingliang, YANG Sheng
    2013, 19(1):  56. 
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    Based on geologic, drilling borehole and geochemical data from the Yushulin oilfield, the source rock in this area is
    characterized by high organic matter abundance and hydrocarbon generation potential. Oil-source correlation shows that the oil
    within the Putaohua reservoir is mostly originated from the first member of the Qingshankou Formation. Reservoir sandstones
    is deposited in distributary channel environment of shallow-water delta, which can be defined as medium porosity and medium
    permeability reservoirs. The reservoir types in this area are mainly controlled by lithology. From southwest to northeast in a plane,
    the number of reservoir increases while the number of water layer decreases. In a vertical plane, the reservoir in the southwest
    area is rich of oil, in the northeast rich of water, while in the middle area, water is rich at the bottom layer and oil is rich at the top
    layer. Our study shows that the area with high maturity of source rock, effective reservoirs, active faults in the time of hydrocarbon
    generation is favourable for hydrocarbon accumulation, which control the behavior of the Putaohua oil reservoir.

    Key issues of 3D geological modeling of paleokarst-cave carbonate reservoir
    HOU Jiagen, MA Xiaoqiang, HU Xiangyang, LIU Yuming, QI Deshan
    2013, 19(1):  64. 
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    Paleokarst cave carbonate reservoir is a kind of special reservoir formed by karstification, and it possesses complex
    development characteristic and extremely strong heterogeneity. So the conventional modeling method of clastic reservoir can
    not be applicable to paleokarst carbonate reservoir. Based on the analysis of state-of-art research, taking the Tahe oilfield as
    an example, several key issues of paleokarst cave reservoir modeling are discussed, including the causes of reservoir, making
    use of soft and hard data for modeling, an improved modeling method by considering vertical zoning of karst, planar partition of
    paleogeomorphology and karst facies. Several problems needed to be improved are discussed as well, including mathematical
    algorithms and characterization of reservoir petrophysical property. We suggest that the characterization of complex shape,
    assembly relations and internal filling characteristic would be topics for future research. The application of multiple point
    geostatistics is feasible. Petrophysical property characterization according to reservoir filling degree and the fillings type is helpful
    to build more accurate geological model.

    Using wavelet frequency analysis to divide sedimentary sequence cycles and isochronous correlation
    WANG Guiwen, XU Jingling, YANG Ning, LAI Jin, ZHAO Xianling 
    2013, 19(1):  70. 
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    In order to improve accuracy and precision of automatic correlation of sequence cycles, to solve problems of difficult
    division, artificial conditions and multiplicity of high resolution sequence cycles, based on previous research and actual well
    logging data, this paper takes the different characteristics of various sedimentary sequence cycles in Chinese continental
    extensional basins as the objective, and conducts the research of wavelet frequency analysis. This paper clarifies the basic theory
    that wavelet frequency analysis is used to divide various sedimentary sequence cycles, and sets up the quantitative standards and
    response standard model for different types of sedimentary sequence cycles. We can realize the goal of applying wavelet frequency
    analysis in sequence boundary recognization, sequence unit division, high-resolution division and isochronous correlation of
    complicated reservoirs, and provide a powerful tool for division and isochronous correlation of sedimentary sequence cycles.

    Investigation of the engineering geology and forecast of the water inflow for the Eling tunnel in Jinggangshan, Jiangxi Province
    XIONG Changlin, XU Xiaoxing, GAO Yingrong, SHU Liangshu 
    2013, 19(1):  78. 
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    The Eling Tunnel, with a length of 10455 m and a maximum depth of 750 m, is located in the Jinggangshan area,
    Southern Jiangxi Province. It is a key engineering structure along the newly built railway from Hengyang to Chalin and to Jian.
    Folding and fracturing structures through the Eling Tunnel are considerably complex and brittle fractures such as joints and
    cleavages are commonly filled with water. The water inflow is a key engineering parameter for the design and construction of
    a tunnel. On the basis of regional-scale engineering geological and structural investigation, several petrological domains with
    different degrees of water penetration were used to test the drilling-wells and hydrological geology. By means of aforesaid work,
    abundant first-hand data of tunnel engineering and hydrological geological condition were obtained. The authors carefully
    analyzed these data related to the tunnel engineering, and identified important parameters for each petrological domain including
    water inflow (m3/d.km) and penetrating-water factor (m/d.km). Then, we divided the tunnel into nine sub-blocks according to

    the survey of geological engineering and hydrological geology. The amounts of water inflow for nine sub-blocks were precisely
    calculated using different methods and formulas. The results indicate that the five sub-blocks, including DK6+625 to DK7+280
    (middle water inflow), DK7+280 to DK7+550 (maximal water inflow), DK8+875 to DK10+085 (middle water inflow), DK11+570
    to DK11+770 (middle water inflow) and DK 13+570 to DK13+930 (middle water inflow), are of high water inflow, probably
    causing the paroxysmal water inflow disaster during the construction of tunnel. Thus we suggest that in the tunnel design stage,
    available safeguard mesurkes such as bracket should be seriously considered, and the quality of tunnel engineering must be
    closely monitored, sub-block by sub-block, during construction. Practical work demonstrated that the aforementioned results have
    an indispensable and forecast value for the design and construction of the Eling Tunnel.

    Hydrocarbon Accumulation of the Jurassic Deeply-buried Lower Assemblage in the Southern Junggar Basin
    SHAO Yu
    2013, 19(1):  86. 
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    Petroleum exploration is expanding to (super-) deeply buried strata worldwidely. Along with this trend, the hydrocarbon
    accumulation in lower assemblage of the deeply-buried Jurassic strata in the southern Junggar Basin in northwest China is
    becoming one of the important targets for basin,s exploration. However threre are few related studies due to relatively low degree
    of exploration. This paper studies source rocks and discusses the controlling factors of hydrocarbon accumulation in the southern
    Junggar Basin, inorder to provide new information on regional exploration and similar studies worldwide. Firstly, we evaluated
    generation potential of the Jurassic source rocks by way of abundance, type and maturity of organic matter in combination with
    geological setting. The Jurassic source rocks are of relatively good quality, having good hydrocarbon generation potential both for
    oil and for gas. Secondly, the well-studied Well Xihu 1 was selected as a representative to confirm the effectiveness of the oil and
    gas generation potential by analyzing hydrocarbon geochemistry. Lastly, through a hydrocarbon accumulation study, we found that
    there are multiple factors that control large-scale and effective hydrocarbon accumulation of deeply-buried strata in the southern
    Junggar Basin. Among them, charge intensity of hydrocarbon and physical property of reservoir were two key factors that need to
    be considered in future.

    Structure types and mineralization in the Zhongzui copper deposit, Jiulong Count
     ZHANG Huihua, FENG Xiaoliang, TANG Gaolin, ZHOU Qing, LI Tongzhu, ZHU Xiangping
    2013, 19(1):  95. 
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    Jianglang Dome lies at the western margin of the Tibetan Plateau, which has been identified as a metamorphic core
    complex. It has good ore-forming physicochemical conditions and is well known in China because it contains several Cu-sulfide
    deposits. Zhongzui copper deposit is characterised by polyphyletic, polyphase and polygenetic features, and has very close
    relationship with the evolution of Jianglang metamorphic core complex. This study is focused on the structure and metallogenic
    conditions of the Zhongzui copper deposit from the northern portion of the Jianglang Dome. On the basis of detailed field
    observations, structural previous, and previous radiometric ages, we suggest that the ore-bearing rock series in Zhongzui copper
    deposit underwent at least six stages of deformation, which were recorded by a series of foliations, and the ore bodies are mainly
    controlled by Variscan ductile shear zone and major Yanshanian gravitational sliding zones. In this contribution, we studied the
    ore-forming process and origin of the Zhongzui copper deposit including its ore-forming source, heating source, metal mobilization,
    enriching process and precipitation locations, established a single metallogenetic model, and presented some prospecting locations
    for similar copper deposits in the Jianglang Dome.

    Sedimentary and tectonic evolution of the Meso-Neoproterozoic strata in the northern margin of the North China block
    PAN Jianguo, QU Yongqiang, MA Rui, PAN Zhongkui, WANG Hailong
    2013, 19(1):  109. 
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    The formation of continental rift basin in the northern margin of the North China block is caused by the breakup of the
    Columbia supercontinent according to previous study and analysis of our eight measured sections. Due to the continued crustal
    extension and creation of oceanic crust, the northern North China block involved into a passive continental margin, which then
    turned into an active margin around 1400 Ma after the deposition of the Tieling Formation. The low-angle subduction of the
    oceanic crust beneath the North China block resulted in a compression environment in the back-arc area (Qinyu Uplift), thus
    leading to the uplift and erosion of the Tieling Formation. Presumably, high-angle subduction of the oceanic crust followed, and
    caused intense rifting and deposition of the Xiamaling Formation accompanied by the intrusion of diabase dykes. The uplift of
    the Xiamaling Formation (or Yuxian Uplift) was related to the collision between the North China block and the adjacent block,
    accompanied by occurrence of the collision-related granites. The time of contractional event coincided with the formation age
    of the Rodinia supercontinent. Neoproterozoic successions might be related to the breakup of the Rodinia supercontinent.
    Quartzarenites and glauconitic sandstones of the Longshan Formation is the earliest deposition after the breakup of the Rodinia
    supercontinent, recording the early transgressive processes.

    Geochemical characteristics of Bayinzhurihe pluton and its tectonic significance, Bayan Obo, Inner Mongolia
    LUO Hongling, WU Tairan, ZHAO Lei, HE Yuankai, JIN Xu 
    2013, 19(1):  123. 
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    The middle segment of northern margin of the North China Plate was influenced by intense tectonic and magmatic
    activity during the Permian. Dozens of intrusions formed an E-W trending magmatic belt that extended from the Dongshenmiao to
    Xianghuang Qi, Inner Mongolia, with a length of 400 km and width of 30 km. As a representative, Bayinzhurihe Pluton consists
    of quartz diorite and hornblende gabbro, which belong to high-potassium calc-alkaline series. They are characterized by low SiO2
    (49.72%~59.34%) and high Al2O3 (15.79%~19.50%) contents, with Mg#=38~44, enrichment in large ion lithophile elements
    (LILE, e.g., Ba=829×10-6~1104×10-6, Sr=502×10-6~726×10-6), relative depletion in high field strength elements (HFSE, e.g.,
    Nb, Ta) in primitive mantle-normalized spidergrams, and right-inclined rare earth element patterns, mostly with slightly negative
    Eu anomalies (δEu=0.63~1.09). Their low Sr/Nd ratios (12~24) and La/Nb ratios (1.33~2.39) may reflect intraplate magmatism
    involved. Hornblende gabbro shows non-arc-like (Nb/Th =9.6-18.4) basalt affinity compositions. LA-ICP-MS U-Pb zircon
    dating of the Pluton yielded an intrusive age of 265±2Ma. Its zircons have εHf(t )= -13.0~-17.2 and t DM
    C=2.12~2.38 Ga, mainly show the characteristics of lower continental crust. These features lead us to conclude that Bayinzhurihe Pluton was generated bymixing of lower crustal-derived mafic melt and minor enriched mantle-derived mafic magma, followed by fractional crystallization,due to crustal extension in post-collisional setting.

    Evolution and Control of Oil Distribution of the Transition Zone in the Central Anticline Transformation Belt, Dongying Sag
    LAO Haigang, CHEN Qinghua, LIU Yan, LI Chenghao, GAO Feng
    2013, 19(1):  133. 
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    According to the analyses of fault attitudes and arrays, a complex transformation belt is recognized in the central
    anticline, Dongying Sag. Research shows that there is significant difference between the eastern and western part of the central
    anticline because of the existence of the transformation belt. In different geological periods, the transformation belt consists of
    different transfer faults. From the late Es4 to Es2 period, Shengtuo transfer fault accommodated different tectonic deformations
    in the central anticline. From the Es1 to Nm period, Ying 66-1 fault was the major transfer fault. Major transfer faults in the
    transformation belt has obvious normal dip-slip components. Experiments show that shale smear formed by transfer faults is far
    better than that in normal faults. Fault dip is negatively correlated with the height of oil column, while normal stress of faults
    positively correlated with oil column height. Normal stress is in the range of 7 to 20 MPa.The distribution of oil and gas around the
    transfer fault mainly occurred in the footwall. Because of strong activities of transfer faults, hydrocarbon in fransition zone is richer
    than other parts of the central anticline structure.

    Thermal History of Paleogene Source Rocks in the Qingdong Sag, Bohai Bay Basin
    CHENG Yanjun, WU Zhiping, LI Wei, WANG Zhengkai
    2013, 19(1):  141. 
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    Based on seismic, logging and geochemical data, the Easy-R o model was adopted to invert the paleogeothermal
    history of the Qingdong sag, and to calculate the paleogeothermal gradient. Based on data of artificial wells and thickness
    of the hydrocarbon source rocks, the maturity and distribution of the upper 4th member and the lower 3th member of the
    Shahejie Formation were discussed and the potential hydrocarbon generation zone was predicted. The results showed that the
    paleogeothermal gradient of the Qingdong Sag was 3.8℃/100m; the maturity of source rocks in the upper 4th member of the
    Shahejie Formation was higher than that of the lower 3th member of the Shahejie Formation which are in the stages of matureover
    mature and mature-low mature, respectively. In a vertical plane, the hydrocarbon generation domain and maturity of source
    rocks of the upper 4th member of the Shahejie Formation was larger than those of the lower 3th member of the Shahejie Formation,
    while in a plane, the main hydrocarbon zone are located on the main part of the Qingdong Sag (North fault-step, north sub-sag,
    middle sub-sag and south sub-sag) and the Qingnan subsag. The western slope of the Qingdong Sag did not reach the hydrocarbon generating threshold.

    Research on geochemical characteristics of thorium for Julong,an deposit, Xiangshan ore field
    MENG Yanning, FAN Honghai
    2013, 19(1):  148. 
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    Julong,an is a large-sized mixed uranium and thorium deposit in the western Xiangshan ore field, Jiangxi Province. On
    the basis of systematic geochemical analysis, this paper discusses distribution characteristics of both trace and major elements
    associated with thorium mineralization in detail. The major elements of Th-rich samples are rich in calcium and phosphorus, and
    characterized by Na2O>K2O. The mono-uranium mineralization is always developed in the early stage of alkali alteration, and the
    thorium mineralization is mainly concentrated in the later stage of pitchblende-fluorite-hydromica alteration halo. The distribution
    patterns of rare earth elements in wall rocks and mineralized samples are different. The thorium mineralization is highly associated
    with rare earth elements, especially with the heavy ones. Trace elements such as Re, Y, Se, Lu are highly correlated with thorium
    mineralization due to formation of associated sulfides and phosphates, such as xenotime.

    Geochronology and geochemical characteristics of metallogenetic pluton in the Youmaling tungsten mining area, northern Guangxi Province, and its geological significance
    YANG Zhen, ZHANG Wenlan, WANG Rucheng, LU Jianjun, XIE Lei, CHE Xudong
    2013, 19(1):  159. 
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    Youmaling tungsten deposit is located in the southern margin of the Miaoershan granitic complex in the northern
    Guangxi province. Its mineralization types are diverse, and the main type is stratoid skarn-type scheelite in outer contact zone of
    the granite body. In this study, we carried out a comprehensive research including zircon U-Pb dating,petrology and geochemical
    studies on the granite related to the tungsten deposit. Petrologically,it is medium-fine grained two-mica granite. LA-ICP-MS
    zircon U-Pb chronology indicates that the granitic pluton emplaced at 212~215 Ma during the Indosinian period. Chemical
    analyses show that the granite has high SiO(2 SiO2=73.73%~78.68%),high alkalies( ALK=6.99%~8.36 %),low Ca and Ti
    (CaO=0.13%~0.96%,TiO2=0.05%~0.27%),and is slightly-strongly peraluminous( ACNK=1.03 ~1.28) ;The granite also
    displays low total REE contents( ΣREE=61.39×10-6~161.22×10-6),with strong negative Eu anomalies( δEu=0.04~0.20),
    and is enriched in Rb,Cs etc. LILEs, Th,U,Ta etc. HFSEs and ore-forming element W( averaging 6.55ppm), depleted in Ba,Sr. These characteristics are similar to the typical highly fractionated S-type granites in Nanling region. Our petrological and
    geochemical data suggest that the granite has the ability to provide materials for formation of tungsten deposit.