bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alkaline Intrusives at the East Foot of the Taihang‐Da Hinggan Mountains: Chronology, Sr, Nd and Pb Isotopic Characteristics and Their Implications
Authors: Guohan YAN , Baoliang XU , Baolei MU , Guanyu WANG , Zhaoshan CHANG , Tingli CHEN , Yongchao ZHAO , Xiaofang WANG , Renhu ZHANG , Guangsheng QIAO , Zhuyin CHU 
Published: September 2010

AbstractBased on the Rb‐Sr isochron dating results, this paper suggests that the alkaline intrusive belt at the east foot of the Taihang‐Da Hinggan Mountains were formed between 135 and 122 Ma. And the alkaline intrusives in the north and south sections of this belt have entirely different Sr, Nd and Pb isotopic characteristics, i.e., all the rocks in the south section have positive ɛSr(t) and negative ɛNd(t) values and all those in the north have the opposite values. On the ɛSr(t) versus ɛNd(t) correlation diagram, the samples from the south are concentrated along the enriched mantle evolution trend lines and nearby, while those from the north fall along the depleted mantle trend lines and nearby. On the Pb isotope composition diagram, most of the samples from the south section fall on the mantle Pb evolution line and nearby, while those from the north lie between the Pb evolution lines of the mantle and the orogenic belt. The above‐stated isotopic characteristics not only indicate that the source rocks of the alkaline intrusives in the south section have a close connection to materials from the enriched mantle reservoir, while those in the north are related to materials from the depleted one, but also reveal that the upper mantle below the North China platform is enriched and that below the Inner Mongolia geosyncline is depleted.
U‐Pb Zircon Dating of the Yeniutan Granitic Intrusion in the Western Sector of the North Qilian Mountains
Authors: Jingwen MAO , Zuoheng ZHANG , Ping JIAN , Zhiliang WANG , Jianmin YANG , Zhaochong ZHANG 
Published: September 2010

AbstractZircons from granodiorite and biotite granite in the Yeniutan granitic intrusion in the western North Qilian Mountains yielded a weighted mean 206Pb/238U apparent age of 460±3 Ma, suggesting that the intrusion originated during the late stage of plate subduction. Its related Ta'ergou and Xiaoliugou deposits are two of the few large tungsten deposits formed in the plate subduction environment in the world. The U‐Pb dating of the zircons from the biotite granite gave a discordant lower intercept age of 183±4 Ma, which implies that the Yanshanian event was probably superimposed on the North Qilian region.
Rock Series and Genetic Types of Granitoids in the Western Kunlun Orogenic Belt, China
Authors: Yaohui JIANG , Xunruo ZHOU , Xingjian RUI , Kunyi GUO , Jurui HE , Wanzhi YANG 
Published: September 2010

AbstractA systematic geological and geochemical study was conducted for the granitoids of different periods in the western Kunlun orogenic belt. The study indicates that the granitoids belong to tholeiitic, calc‐alkaline, high‐K calc‐alkaline, alkaline and shoshonitic series, and that there are 5 genetic types, i.e., I‐, S‐, M‐, A‐ and SH‐type, of which SH‐type is first put forward in this paper, which corresponds to shoshonitic granitoids.
The Altun Fault: Its Geometry, Nature and Mode of Growth
Authors: Junwen CUI , Li LI , Jingsui YANG , Yongjun YUE , Pengwu LI , Jianxin ZHANG , Wen CHEN 
Published: September 2010

AbstractThe Altun (or Altyn Tagh) fault displays a geometry of overlapping of linear and arcuate segments and shows strong inhomogeneity in time and space. It is a gigantic fault system with complex mechanical behaviours including thrusting, sinistral strike slip and normal slip. The strike slip and normal slip mainly occurred in the Cretaceous—Cenozoic and Plio‐Quaternary respectively, whereas the thrusting was a deformation event that has played a dominant role since the late Palaeozoic (for a duration of about 305 Ma). The formation of the Altun fault was related to strong inhomogeneous deformation of the massifs on its two sides (in the hinterland of the Altun Mountains contractional deformation predominated and in the Qilian massif thrust propagation was dominant). The fault experienced a dynamic process of successive break‐up and connection of its segments and gradual propagation, which was synchronous with the development of an overstep thrust sequence in the Qilian massif and the uplift of the Qinghai‐Tibet plateau. With southward propagation of the thrust sequence and continued uplift of the plateau, the NE tip of the Altun fault moved in a NE direction, while the SW tip grew in a SW direction.
Thrusting and Exhumation Processes of a Bounding Mountain Belt: Constraints from Sediment Provenance Analysis of the Hefei Basin
Authors: Shaofeng LIU , Wencan LIU , Shaowu DAI , Siji HUANG , Wuyun LU 
Published: September 2010

AbstractLithic (or gravel) composition analyses of the Jurassic Sanjianpu Formation and Fenghuangtai Formation in the Hefei basin show that the sediment provenance consists mainly of four kinds of rock units: the basement metamorphic complex, granitic rocks, medium‐ and low‐grade metamorphic rocks, and sandy and muddy sedimentary rocks, which are distributed along the bounding thrust belt. The whole stratigraphic section can be divided into 2 lithic sequences and 7 subsequences. The regular distribution and changes of lithic fragments and gravels in lithic (or gravel) sequences reflect that the bounding thrust belt of basin has undergone 2 thrusting cycles and 7 thrusting events. Lithic (or gravel) composition analyses of the basin fully reveal that the northern Dabie basement metamorphic complex was exhumed on the earth's surface in the Middle and Late Jurassic, and extensive intermediate and acid intrusive rocks were developed in the southern North Huaiyang or northern Dabie Mountains during the basin's syndepositional stage.
Post‐Collisional Ductile Extensional Tectonic Framework in the UHP and HP Metamorphic Belts in the Dabie‐Sulu Region, China
Authors: Shutian SUO , Zengqiu ZHONG , Zhendong YOU , Zeming ZHANG 
Published: September 2010

AbstractThe present‐day observable tectonic framework of the ultrahigh‐pressure (UHP) and high‐pressure (HP) metamorphic belts in the Dabie‐Sulu region was dominantly formed by an extensional process, mostly between 200 and 170 Ma, following the Triassic collision between the Sino‐Korean and Yangtze cratons. The framework that controls the present spatial distribution of UHP and HP metamorphic rocks in particular displays the typical features of a Cordilleran‐type metamorphic core complex, in which at least four regional‐scale, shallow‐dipping detachment zones are recognized. Each of these detachment zones corresponds to a pressure gap of 0.5 to 2.0 GPa. The detachment zones separate the rocks exposed in the region into several petrotectonic units with different P‐T conditions. The geometry and kinematics of both the detachment zones and the petrotectonic units show that the exhumation of UHP and HP metamorphic rocks in the Dabie‐Sulu region was achieved, at least in part, by non‐coaxial ductile flow in the multi‐layered detachment zones, and by coaxial vertical shortening and horizontal stretching in the metamorphic units, under amphibolite‐ to greenschist‐facies conditions, and in an extensional regime. All ductile extensional deformations occurred at depths below 10 to 15 km, i.e. below the brittle/ductile deformation transition.
Oil Source and Entrapment Epoch of the Ordovician Oil Reservoir in the Kongxi Burial‐Hill Zone, Huanghua Depression, North China
Authors: Tieguan WANG , Feiyu WANG , Hong LU , Chiyin YANG , Qianjin LIAO , Jiansheng ZHOU 
Published: September 2010

AbstractAn oil flow obtained from the Middle Ordovician Fengfeng Formation carbonate reservoir in the well KG‐3, Kongxi burial‐hill zone in 1993 marked a breakthrough in petroleum exploration of the high‐mature Lower Palaeozoic strata, North China. Both the Lower member of the Fengfeng Formation and the Second Member of the Upper Majiagou Formation in the Middle Ordovician are supposed to be the main source beds. Oil generation peaks range from 1.0% to 1.6% in Ro, showing a “lag effect” of oil generation in high‐mature carbonate source rocks under multicyclic tectonic movement conditions. The Kongxi burial‐hill zone adjoins a potential Ordovician source kitchen. The KG‐3 Ordovician burial‐hill reservoir has undergone two oil filling events, i.e., an early event in the Late Carboniferous‐Permian and a more significant late event in the early Eogene.
Quantitative Modelling of Multiphase Lithospheric Stretching and Deep Thermal History of Some Tertiary Rift Basins in Eastern China
Authors: Changsong LIN , Yanmei ZHANG , Sitian LI , Jingyan LIU , Zhigang TONG , Xiaozhong DING , Xichen LI 
Published: September 2010

AbstractThe stretching process of some Tertiary rift basins in eastern China is characterized by multiphase rifting. A multiple instantaneous uniform stretching model is proposed in this paper to simulate the formation of the basins as the rifting process cannot be accurately described by a simple (one episode) stretching model. The study shows that the multiphase stretching model, combined with the back‐stripping technique, can be used to reconstruct the subsidence history and the stretching process of the lithosphere, and to evaluate the depth to the top of the asthenosphere and the deep thermal evolution of the basins. The calculated results obtained by applying the quantitative model to the episodic rifting process of the Tertiary Qiongdongnan and Yinggehai basins in the South China Sea are in agreement with geophysical data and geological observations. This provides a new method for quantitative evaluation of the geodynamic process of multiphase rifting occurring during the Tertiary in eastern China.
Hydrothermal Alteration Zoning and Kinetic Process of Mineral‐Water Interactions
Authors: Ronghua ZHANG , Shumin HU , Yanfeng SU 
Published: September 2010

AbstractThis study reports the kinetic experimental results of albite in water and in KCl solution at 22 MPa in the temperature range of 25 to 400°C. Kinetic experiments have been carried out in an open flow‐through reaction system (packed bed reactor). Albite dissolution is always incongruent in water at most temperatures, but becomes congruent at 300°C (close to the critical point 374°C). At temperatures from 25 to 300°C, the incongruent dissolution of albite is reflected by the fact that sodium and aluminum are easily dissolved into water, from 300 to 400°C it is reflected by silicon being more easily dissolved in water than Al and Na. Maximum albite dissolution rates in the flow hydrothermal systems have been repeatedly observed at 300°C, independent of flow rates.The kinetic experiments of albite dissolution in a KCl aqueous solution (0.1 mol KCl) indicate that the dissolution rate of albite increases with increasing temperature. Maximum silicon release rates of albite have been observed at 400°C, while maximum aluminum release rates of albite at 374°C. The reaction rates of albite also depend on the potassium concentration in the aqueous solution.These results can be used to interpret the mechanism for forming hydrothermal alteration. The kinetic experiments of mineral‐aqueous solutions interactions in the hydrothermal system from 25 to 400°C and at 22 MPa indicate that the formation of the feldspar‐mica‐kaolinite zoning occurring in some ore deposits may depend not only on the mineral stability but also on the kinetics of feldspar hydration, which is affected by the water property variation when crossing the critical point.
Origin and Superposition Metallogenic Model of the Sandstone‐type Uranium Deposit in the Northeastern Ordos Basin, China
Authors: Ziying LI , Anping CHEN , Xiheng FANG , Guangxi OU , Yuliang XIA , Ye SUN 
Published: September 2010

AbstractThis paper deals with the metallogenic model of the sandstone type uranium deposit in the northeastern Ordos Basin from aspects of uranium source, migration and deposition. A superposition metallogenic model has been established due to complex uranium mineralization processes with superposition of oil‐gas reduction and thermal reformation.
Typomorpic Characteristics of the Major Minerals in the Puziwan Gold Deposit, Datong, Shanxi, China
Authors: Min QING , Cuiyi NIU , Shibin LEI 
Published: September 2010

AbstractUtilizing theories of minerageny and prospecting mineralogy, the authors studied the attitude, morphotype and chemical composition of metallic minerals of pyrite, gold, chalcopyrite, galena and sphalerite, non‐metallic minerals of quartz, carbonate, dolomite and rutile in the Puziwan gold deposit. The study shows the following results. (1) The mineral assemblage is complex and the species of sulfide are abundant with occurrences of sulfosalt minerals. (2) The composition in the minerals is complex and there rich micro elements, including As, Sb, Bi, Se, Te, Au, Ag, Cu, Pb, Zn, and Cr, Ni, V. The typomorphic characteristics of the association of the elements and their specific value suggest that gold mineralization is associated with shallow magmatic hydrothermal activity, the ore‐forming fluid is the mixture of abundant rising alkali magmatic water originating from the mantle or the lower crust and the descending acid atmospheric water. (3) Ankerite, Fe‐rich sphalerite, granular Ti‐rich rutile are widely distributed, which indicate great denudation depths, high mineralization temperature. The deposit is found in the middle and shallow positions of the porphyry series. The deep layers are not favorable for gold mineralization. (4) Copper minerals are rich in the ores and sulfides have high content of copper, suggesting possible porphyry‐type Cu (Au) mineralization in deep positions and the surrounding areas.
Yangshan Gold Deposit: The Largest Carlin and Carlin‐Iike Type Gold Deposit in China
Authors: Fengzeng YAN , Qiangzhi LI 
Published: September 2010

AbstractGold Headquarter of the CAPF has discovered the Yangshan super large‐scale gold deposit in Gansu Province, which is a great breakthrough of gold exploration and prospecting in Western Qinling Mountains of China. The gold resources of this deposit achieved 308 tons with increasing potentials. Preliminary geological investigations indicate that the Yangshan gold deposit is located in the intra‐continental collision orogenic belt; and the deposit was formed during the continent‐continent collision orogenic processes. The geological characteristics of the deposit are similar to that of the typical Carlin‐type gold deposits, while differences still exist. The ore‐forming background is notably different from the Carlin gold deposit province in the United States; and the ore‐forming fluids are similar with that of the orogenic‐type gold deposit. Accordingly, the Yangshan gold deposit is a transitional type between the Carlin‐type and the orogenic type gold deposits. At present, the Yangshan gold deposit is the largest Carlin and Carlin‐like type gold deposit that is ever discovered in China. Researches on metallogeny, metallogenic model and ore‐enrichment regularities of the Yangshan gold deposit are crucial to meet the pressing needs of the current geological investigation and ore exploration of the deposit.
A Preliminary Study on Fluid Inclusions and Mineralization of Xitieshan Sedimentary‐Exhalative (SEDEX) Lead‐Zinc Deposit
Authors: Lijuan WANG , Xinyou ZHU , Jingbin WANG , Jiniu DENG , Yuwang WANG , Heping ZHU 
Published: September 2010

AbstractThe Xitieshan lead‐zinc deposit is located at the northern margin of the Qaidam Basin, Qinghai Province, China, and had developed a complete marine sedimentary‐exhalative system. Our preliminary study of ore‐forming fluids shows that fluid inclusions in quartz from altered stockwork rocks that represent the pipe facies have a wide range of temperature and salinity. The intense fluid activities are characteristics of the pipe facies of the exhalative system. Fluid inclusions in carbonates near the unstratified ore bodies hosted in the thick‐bedded marble which represents vent‐proximal facies are large in size and have moderate to high temperatures. They represent unerupted sub‐seafloor fluid activity. Fluids in altered stockwork rocks and carbonates have similar H2O‐NaCl‐CO2 system, both belonging to the sedimentary‐exhalative system. The fluids migrate from the pipe facies to the unstratified ore bodies. Boiling of the fluids causes the separation of CO2 vapor and liquid H2O. When the fluids migrate into the unconsolidated thick‐bedded marble, the escape of CO2, decreasing temperature and pressure as well as some involvement of seawater into the fluids result in the unmixing of fluids with high and low salinity and deposition of ore‐forming materials. The two unmixed fluids were trapped in unconsolidated carbonates and the ore‐forming materials were deposited in the unconsolidated carbonates to form the sedimentary‐exhalative type unstratified ore bodies. The ore‐forming temperature of unstratified ore bodies is up to high temperature indicating that there is a huge ore‐forming potential in its deep.
Diagenesis and Metamorphism of Triassic Flysch Along Profile Zoigê‐Lushan, Northwest Sichuan, China
Authors: Hejing WANG , RAHN M. , Xiaofeng TAO , Nan ZHENG , Tingjing XU 
Published: September 2010

AbstractWe used illite and chlorite crystallinities, index minerals, mineral assemblages, polytype and domain size of white mica, electron microprobe analysis (EMPA), b0 geobarometer and chlorite geothermometer to quantify the diagenetic and metamorphic overprint on the Triassic flysch formations in the Songpan‐Garzê orogen along profile Zoigê‐Lushan, northwest Sichuan. Two anchizones, two epizones, one diagenetic zone and a transition belt in‐between them are defined on the basis of the obtained data. Illite crystallinity correlates strongly with the best mean domain size of mica and moderately with chlorite crystallinity. 2M1 white mica polytype are observed within the epizone whilst 2M1 and 1M polytypes occur in the anchizone and diagenetic zone. Epizonal metamorphism reached maximum temperatures of 370°C±21°C at low‐to intermediate pressure conditions. Clay minerals underwent Ostwald ripening during metamorphism. Rocks from both sides of the Longmenshan fault reveal contrasting degrees of metamorphic overprint: on the northwest side of the Longmenshan fault, epimetamorphic conditions contrast with diagenetic rocks on the southeast side.
Geochemical Mapping—Evolution of Its Aims, Ideas and Technology
Authors: Xuejing XIE 
Published: September 2010

AbstractThe development of geochemical mapping progressed from local geochemical prospecting through regional geochemical exploration and regional geochemical mapping to national and global geochemical mapping. This paper discusses the evolution of aims, ideas and methodology of geochemical mapping in Western countries, Russia and China. The sophistication of geochemical mapping methodology will make great contributions to solving resources and environmental problems in the 21st century.
Weathering‐pedogenesis of Carbonate Rocks and Its Environmental Effects in Subtropical Region
Authors: Lijun ZHU , Shouyang HE , Jingyang LI 
Published: September 2010

AbstractWe investigated the weathering‐pedogenesis of carbonate rocks and its environmental effects in subtropical regions of China. The investigation demonstrated that the weathering‐pedogenesis of carbonate rocks is the process of a joint action of corrosion and illuviation and metasomatism in subtropical region. It is characterized by multi‐stage, multi‐path and multi‐style. With the persisting development of weathering‐pedogenesis of carbonate rocks, metasomatic pedogenesis progressively became the main process of the weathering‐pedogenesis and the dominant style of formation of minerals. And it proceeds through the whole process of evolution of the weathering‐pedogenesis of carbonate rocks. The stage evolution of weathering‐pedogenesis of carbonate rocks and the fractionation evolution of newly produced minerals are characterized by obvious vertically zoning structures and the rules of gradation of elements geochemical characteristics in the carbonate rocks weathering profiles. The geochemical process of weathering‐pedogenesis of carbonate rocks can be divided into three geochemical evolution stages, i.e., the Ca, Mg‐depletion and Si, Al‐enrichment stage; the Fe, Mn enrichment stage and the Si‐depletion and Al‐enrichment stage in the subtropical regions. Consistent with the three geochemical evolution stages, the sequence of formation and evolution of minerals can be divided into the clay mineral stage; the Fe, Mn oxide and the gibbsite stage. The influence of weathering‐pedogenesis of carbonate rocks on the chemical forms of heavy elements is mainly affected via newly produced components and minerals in the process of weathering‐pedogenesis, e.g., iron oxide minerals and organic matters. The important mechanism for the mobilization, transport and pollution of F and As is affected the selective adsorption and desorption of F and As on the surface of iron oxide minerals in the subtropical karst zones, i.e., the selective adsorption and desorption on mineral surfaces of newly produced minerals in the process of weathering‐pedogenesis control the geochemical behavior of elements on the Earth's surface and environmental quality in subtropical regions.
Heavy Metal Distributions and Source Tracing in the Lacustrine Sediments of Dongdao Island, South China Sea
Authors: Xiaodong LIU , Liguang SUN , Xuebin YIN , Yuhong WANG 
Published: September 2010

AbstractThe levels and depth distributions of As, Cd, Cu, Zn, Pb, Hg, Fe and Mn in two sediment cores DY2 and DY4 collected from the “Cattle Pond” of Dongdao Island, South China Sea, were determined and analyzed with the main objective to identify the sources of these elements and evaluate the corresponding sedimentological and geochemical processes. Lithological characters and sedimentary parameters such as LOI950°C, CaO, LOI550°c and TOC indicate that the depth of 96 cm and 87 cm are the critical points for DY2 and DY4 cores, respectively. As, Cd, Cu, Zn, Hg and P are remarkably enriched in the ornithogenic sediments above the critical depth points; their concentration‐versus‐depth profiles are similar to those of TOC and LOI5S0 c; the ratios of As, Cd, Cu, Zn, Hg over Ca are significantly correlated with P/Ca. Statistical and comparative analyses of these elements' levels in the ornithogenic sediments of DY2 and DY4 strongly suggest that seabird droppings are the main source of these elements. Additionally, for the upper sediment layers of DY2 and DY4 cores, Fe oxide sorption mechanism, like organic matter, may also play an important role in the abundances of heavy metals. Heavy metal Pb has geochemical characteristics distinctly different from those of As, Cd, Cu, Zn, Hg and P, and its isotope composition indicates an origin of anthropogenic emissions from the surrounding countries. These geochemical characteristics in the orinithogenic sediments of Xisha Islands are compared with the studies in the remote Antarctic and Arctic regions.