bluuebunny/crossref_metadata_2025_split huggingface dataset:
Yixunite and Damiaoite—A Twin of New Native Alloys of Indium and Platinum from the Yanshan Mountains
Authors: Zuxiang Yu 
Published: September 2010

AbstractYixunite and damiaoite were found in a cobalt‐ and copper–bearing platinum ore vein of a contact metasomatic deposit. The chief ore minerals are bornite, chalcopyrite, magnetite and carrollite. The platinum minerals include moncheite, sperrylite, daomanite, cobalt malanite and cooperite. Yixunite and damiaoite occur as immiscible globules, 1.0 to 2.0 mm in diameter. Yixunite is always in the central part of a globule. It is opaque with metallic lustre, bright white colour and black streak. HM=5.8; VHN50 = 634 kg/mm2 (573–681 kg/mm2); insoluble in HCl, HNO3, HF or H3PO4; no cleavage; no magnetism. Density is hard to measure because of small grain size. Calculated density = 18.21 g/cm3. Reflective colour is bright white with a yellowish tint. Isotropic. The mean analytical results (ranges) (%) are: Pt 82.8 (81.8–83.6), In 16.4(15.6–17.1) and total 99.2. The empirical formula (based on 4 atoms) is Pt2.993 In1.007. The five strongest lines of X–ray diffraction (hki, d, I) are 111, 2.30 (100); 200, 1.99(60); 202, 1.411 (40); 311, 1.203 (80); 222, 1.151(40). Space group: Pm3m with a = 0.3988(3) nm and Z= 1. Damiaoite occurs as single globules or was exsolved from yixunite. Opaque with metallic lustre; bright white colour with black streak; HM = 5.3; VHN50 = 485 kg/mm2 (434–529 kg/mm2); insoluble in HCl, HNO3, HF or H3PO4; cleavage: no; magnetism: no. Density: hard to measure because of small grain size. Calculated density = 10.95 g/cm3. Reflective colour is bright white with a yellowish tint. Isotropic. The mean analytical results (ranges) (%) are Pt 45.6 (45.4–46.0), In 53.5 (52.4–53.9), total 99.1. The empirical formula (based on 3 atoms) is P1.002 In1.998. The six strongest lines of X–ray diffraction (hkl. d. I) are 220,2.25 (100); 311,1.92 (60); 400,1.59 (60); 422,1.299 (80); 440,1.125 (60); 620,1.006 (70). Space group: Fm3m with a = 0.6364 (3) nm and Z = 4.
The Equilibrium Coefficient Kp and Petroleum Exploration: Design of the New Generation of Petroleum Exploration Instrument
Authors: Weiheng FENG , Yun FENG 
Published: September 2010

Abstract  The main reason why the application of nuclear technology in petroleum exploration has not yet been accepted by most exploration workers is that they are not clear about the homologous distribution features of oil and gas fields and radioactive radiation. The authors hold that the disequilibrium of uranium, radium and radon as a natural radioactive series is the basic feature in the use of this technology in petroleum exploration. The invention Gamma‐ray Spectral Measurement of the Equilibium Coefficient Kp and Its Embodiment of the senior author now can readily solve that problem and replace the impedient measure of normalization of uranium and potassium to thorium that had to be proposed before. Application of this impedient measure has some limitations. In areas where the surface is covered by beach or river sands, thorium minerals such as monazite may be concentrated by placering. This could result in local thorium highs that would yield local uranium and potassium lows after normalization to thorium, and these would constitute false anomalies.This paper elucidates the relation between the equilibrium coefficient Kp and petroleum exploration and points out that immediately over petroleum the radioactive equilibrium is biased with uranium, while at peripheries of the petroleum reservoir the equilibrium is biased with radium; therefore, the true uranium content immediately over petroleum is not lower but higher, and by constrast the uranium content at peripheries of the petroleum reservoir is not higher but lower. This paper further introduces the main technical requirements for the instrument used in petroleum exploration with nuclear technology and the design basis and work procedure of the petroleum‐field effective equilibrium coefficient ground detector and finally introduces the applicability of the detector in petroleum exploration through the distribution features of the equilibrium coefficient Kp of five types of trap‐type petroleum deposits.
New Discovery of the Early Cretaceous Volcanic Rocks on the Barton Peninsula, King George Island, Antarctica and Its Geological Significance
Authors: Xiangshen ZHENG , Haiqing SANG , Ji QIU , Jiaqi LIU , Ik LEE Jong , Hyeoncheol KIM 
Published: September 2010

AbstractAges determined with the 40Ar/39Ar isotopic system affirms the Early Cretaceous volcanic activity in the Barton Peninsula, King George Island, Antarctica. Two specimens of basaltic andesite collected from the lower‐most volcanic sequence of the peninsula were irradiated and analyzed in different experiments, yielding an identical age spectrum, and two magmatic thermal events of the Early Cretaceous (120.4±1.6 Ma, 119±1 Ma) and Early Tertiary (53.1±1.5 Ma, 52±1 Ma) are distinguished. The former is interpreted to represent the primary cooling age of basaltic andesite, whereas the latter is the thermal reset age caused by the intrusion of granitic pluton. These new ages clearly indicate that volcanism was active during the Early Cretaceous on the Barton Peninsula and that intensive hydrothermal alteration and mineralization of Mesozoic volcanic rocks resulted from Tertiary magmatism.
Basement Characteristics and Crustal Evolution of the Copper‐Gold Metallogenic Belt in the Middle and Lower Reaches of the Yangtze River: Some Isotope Constraints
Authors: Taofa ZHOU , Shucang YUE 
Published: September 2010

AbstractStudies of the Pb, Sr and Nd isotopic composition of Mesozoic intrusive rocks indicate that the basement of the copper‐gold metallogenic belt of the middle and lower reaches of the Yangtze River has “two‐layer structure” and partly has “multi‐layered structure”, and is inhomogeneous and shows the distinct feature of E‐W provincialism. The calculated model lead ages (t1) are mostly greater than 2600 Ma, and the model neodymium ages (TDM) vary from 953 to 2276 Ma and concentrate in two time intervals: 1800–2000 Ma and 1200–1600 Ma. It is concluded that the basement of the MBYR is composed of the Late Archaeozoic to Middle Proterozoic metamorphic series and that the crust was initiated in the Archaean and continued to grow in the Early and Middle Proterozoic, and the proportion of new crust formed by mantle differentiation during the Late Proterozoic is low.
Characteristics of the Geotectonics in South China and Their Constraints on Primary Diamond
Authors: Wenquan TANG , Chaomin BAO 
Published: September 2010

AbstractThe Asian continent is one of the best places in the world to study continental dynamics. In this region the tectonic framework of the South China plate is related to the activity of the Pacific plate and Indian plate since the Mesozoic. In the South China plate, as the ophiolitic mélange of the middle Proterozoic in the Shaoxing‐Yingtan‐Tengxian‐Beihai faulted zone was confirmed to be a subducting ocean, the evolution of the Yangtze block and Cathaysian block, which are located on both sides of the fault zone, becomes clearer and clearer. A primary diamond deposit, which was first found by Bao Chaomin and his colleagues in Longyou County of Zhejiang Province in 1998, originated from kimberlitoid pipes. The pipes are located in the Cretaceous basin beside this deep fault and the diamond‐bearing pipe was formed deep within a favourable geological structure. Diamond there occurs as octahedral crystals without visual impurities. There are more than 100 similar pipes in the area, which have been poorly studied so far, so this area should have great prospects for diamond exploration.
Pulsation Solution to the Equation of Earth's Gravitational Field (Main Outcome)
Authors: Zhi JIANG , Layers Spherical , Model Density 
Published: September 2010

AbstractUsing d'Alembert equation as the approximation of Einstein's equation, a solution is given in this paper to the time‐dependent gravitational equation of the Earth in consideration of the Earth's features, which describes the characteristics of pulsation of the Earth and the structures of spherical layers of its interior, thus providing a theoretical basis for establishing the idea of mantle pulsation.
Geochronology and Significance of Granites Associated with Gold Deposits in the Jidong Area, China
Authors: Kang GUAN , Zhenkuan LUO , Youshou QIU , Laicheng MIAO , Yumin QIU , MCNAUGHTON Neal , GROVES David 
Published: September 2010

AbstractThe Jidong area is located on the north margin of the North China craton. It is a nucleus composed of the oldest rocks in China. Precambrian metarnorphic rocks with various Phanerozoic granitoids invaded are widespread. Gold deposits here have close spatial relations to granitoids. Some deposits occur within them and others in the outer zone of the contact belt of the intrusion, extending thousands of metres. There have been controversial views in regard to the relations of the deposits to the intrusions although traditional techniques have been used to date the intrusions. In order to solve such a problem, the SHRIMP technique was adopted to date the U‐Pb ages of zircon collected from the Yuerya intrusion which hosts the large‐sized Yuerya Au deposit and Qingshankou intrusion 2 km away from the Jinchangyu (larger‐sized) Au deposit. Analysis shows that the ages of 175±1 Ma and 174±3 Ma for Yuerya intrusion and the age of 199±2 Ma for Qingshankou granite indicate the Early Yanshanian stage of the Mesozoic. The Yuerya intrusion also contains inherited zircon aged at about 2500 Ma, indicating that part of its source materials are Archaean metamorphic rocks. In addition to the SHRIMP data of this study, a great deal of data related to the alteration of Au deposits indicate the formation of the deposits at the Yanshanian stage of the Mesozoic, so the ore formation of Au deposits is inferred to relate to granitic intrusion.
Geochemistry of Alkali‐rich Igneous Rocks of Northern Xinjiang and Its Implications for Geodynamics
Authors: Zhenhua ZHAO , Zhenghua BAI , Xiaolin XIONG , Houjun MEI , Yixian WANG 
Published: September 2010

AbstractFive nearly E‐W‐trending alkali‐rich igneous rock belts are distributed from north to south in northern Xinjiang, and they are composed mainly of riebeckite, K‐feldspar granite and high‐K and medium‐K calc‐alkaline volcanic rocks and shoshonite. They were mainly emplaced or erupted between the Carboniferous and Permian. The compositions of Sr, Nd, Pb, and O isotopes imply that their principal resource materials are derived from the upper mantle or juvenile crust, indicating obvious continental growth in the Phanerozoic. The trace element association implies that their tectonic settings are within plate and volcanic arc for alkali‐rich granites, and post‐collisional are, late oceanic are and continental are for alkali‐rich volcanic rocks. An archipelago model was suggested for the tectonic evolution in northern Xinjiang. It can be named the central‐Asia‐type orogeny, which is different from the so called circum‐Pacific ocean‐continent‐type tectonics or the Alpine‐Himalayan continent‐continent‐collisional orogeny.
Application of the Landsat‐5TM Image Data in the Feasibility Study of Mudflow Hazards in the Southern Taihang Mountains
Authors: Yanxiao QIAO , Miwen LI 
Published: September 2010

AbstractThe Taihang Mountains area is an area in North China where serious mudflow hazards take place frequently. The hazards often obstrust traffic and make it difficult to carry out conventional ground investigations of the mudflow hazards. This paper introduces the feasibility study of mudflow hazards by using Landsat‐5TM data. The study has achieved a great success through adopting both the faint spectral enhancement technique for mudflow fans (or other depositional areas) and comprehensive study of the environmental background of pregnant mudflows. Thus, remote sensing as a fast, convenient, low‐cost and effective technical method can be used to recognise the situation of mudflow hazards so that effective rescue can be provided.
The Effect of Geologic Structures on the Control of Floods in the Middle Yangtze River Valley
Authors: Qianming Tong 
Published: September 2010

AbstractThis paper discusses the role of geologic structures in the occurrence of floods and how to prevent flood in the middle reaches of the Yangtze River, and gives the author's suggestion that the Luoshan Qiakou be expanded and the land reclaimed from Dongting Lake be returned to the lake in compliance with the law of geology.
Heat Flow Pattern in the Mainland of China and Its Geodynamic Significance
Authors: Yang WANG , Jiyang WANG , Liangping XIONG 
Published: September 2010

AbstractOn the basis of 723 heat flow measurements in the mainland of China and over 2000 data from the global heat flow data set, the authors compiled the heat flow map of the mainland of China and its adjacent areas to exhibit the overall variation of the heat flow pattern in the mainland. The heat flow pattern of the mainland is complex, and can not be simply summarized as “low in the north and west and high in the south and east”. Significant difference exists between eastern and western China in the spatial pattern of heat flow. Divided by the 105°E meridian, heat flow values in eastern China show a westward‐decreasing trend; and a northward variation is observed in western China. The high‐heat flow regions correspond to tectonically active belts such as Cenozoic orogens and extensional basins, where mantle heat flow is high; and the low‐heat flow regions correspond to stable units such as the Tarim and Yangtze platforms. This heat flow pattern is controlled by India‐Asia collision in the west and Pacific plate subduction in the east. The lateral variation in lithospheric strength corresponds to the heat flow variation, and there is a generally reversely proportional relation between heat flow and lithospheric strength in the mainland of China. The mosaic pattern of present deformation in the mainland results from lateral rheological heterogeneity. The good coincidence between weak strength domains and seismic zones demonstrates the intrinsic relation between the strength heterogeneity and regional seismicity pattern in the mainland of China.
Error Propagation in Geochemical Calculations of Groundwater‐Mineral Interactions: A Case Study from the Pingdingshan Coalfield, Henan
Authors: Guangcai WANG , Shu TAO , Zhaoli SHEN , Zuoshen ZHONG 
Published: September 2010

AbstractThe WATEQ4F‐based “multiple step method”, or the method of running WATEQ4F repeatedly, was used to evaluate the error propagation in computations of water‐mineral interactions under the circumstances of constant and varied temperatures due to the uncertainties of input variables. The results show the following: the errors of water chemistry analysis can strongly affect the modelling results of water‐mineral reactions; different input variables (errors) have different effects on the saturation indices (S.I.) of different minerals; in many cases, the S.I. errors of minerals change with temperatures.
Kinetics of Hydrothermal Reactions of Minerals in Near‐critical and Supercritical Water
Authors: Ronghua ZHANG , Shumin HU , Xuetong ZHANG 
Published: September 2010

AbstractThis work presents new experimental results on the kinetics of mineral dissolution in near‐critical and supercritical water in a temperature range (T) from 25 to 400°C and a constant pressure of 23 MPa. Kinetic experiments were carried out by using a flow reactor (packed bed reactor) of an open system. The dissolution rates of albite and magnetite were measured under these experimental conditions. Na, Al and Si release rates for albite dissolution in water were measured as a function of the temperature and flow velocity in the reaction system. The maximum release rates of Na, Al and Si of albite dissolution in the hydrothermal flow systems under different flow velocities were always obtained at 300°C, that is to say, the maximum albite dissolution rates in the flow systems, regardless of different flow rates, were repeatedly measured at 300°C. Results indicate a wide fluctuation in albite dissolution rates occurring close to the critical point of water. The dissolution rates increased when the temperatures increased from 25 to 300°C and decreased when the temperatures increase from 300 to 400°C. At some flow velocities, the dissolution rates rose as the temperature surpassed 374°C. Albite dissolution was incongruent in water at most temperatures. It was only at 300°C that albite dissolution was congruent. The albite dissolution from 25 to 300°C (at 23 MPa) will change from incongruent to congruent, whereas from subcritical 300 to 400°C (at 23 MPa), the dissolution will change from congruent to incongruent. The release ratio of Al/Si (or Na/Si) is positive at T<300°C, and it is negative at T>300°C. The dissolution rates of magnetite in water increased with increasing T until T at the critical point of water or around it. The authors believe that this is caused by the wide fluctuations in water properties under the conditions from the near‐critical to supercritical state.
Mineral Surface after Reaction with Aqueous Solution at High Temperatures and Pressures
Authors: Xuetong ZHANG , Ronghua ZHANG , Shumin HU , Wenbin YU 
Published: September 2010

AbstractThis work presents new experimental results on surface chemistry of reacting minerals and interface kinetics between mineral and aqueous solutions. These experiments were carried out using a flow reactor (packed bed reactor) of an open system as well as a continuous stirred tank reactor, CSTR. The authors measured reaction rates of such minerals as zeolite, albite and carbonate (rhodochrosite, dolomite) in various solutions, and tested corresponding mineral surface by using SEM, XPS, SIMS, etc. This paper mainly presents the experimental results of zeolite dissolution in water and in low pH solutions at room temperature, and dolomite dissolution at elevated temperatures. The results show that the release rates of Si, Al and Na of zeolite are different in most cases. The incongruent dissolution of zeolite is related to surface chemical modifications. The Na, Al and Si release rates for dissolution of albite and zeolite in water and various solutions were measured as a function of temperature, flow velocity, pH and solution composition in the reaction system. In most cases, dissolutions of both albite and zeolite are incongruent. Dissolution of dolomite is also incongruent in most cases and varied with T, pH, and nature of aqueous solutions. For dolomite dissolution, the release rates of Mg are less than those of Ca at high temperatures as T increases from 25 to 300°C. SIMS study indicates that the contents of Al, Na and Si in the leached layer of zeolite or albite surface, change with the distance from the surface, exhibiting a non‐linear behaviour within a thickness range of 1000%. The distributions of Ca, Mg, Mn, H and Cl in the leached surface layer of carbonate have a non‐linear behaviour too.
SHRIMP U‐Pb Dating of Zircons of a Dark Eclogite and a Garnet‐bearing Gneissic Granitic Rock from Bixiling, Eastern Dabie Area, Anhui Province: Isotope Chronological Evidence of Neoproterozoic UHP Metamorphism
Authors: Yuqi CHENG , Dunyi LIU , WILLIAMS I.S. , Ping JIAN , Yuxun ZHUANG , Tianshan GAO 
Published: September 2010

AbstractThe paper reports SHRIMP U‐Pb zircon data of a dark eclogite and a post‐eclogite garnet‐bearing gneissic granitic rock from the Bixiling area, Yuexi County, Anhui Province, in the eastern Dabie Mountains. The eclogite, which is metamorphosed basic tuff, contains very scarce zircons in omphacite or garnet, but more zircons in quartz. They usually exhibit a double‐layered texture, as shown clearly in cathodoluminescence images. Their inner main parts give a 206Pb/238U age of 757±7 Ma, representing the approximate age of the high‐pressure (HP)‐ ultrahigh‐pressure (UHP) metamorphic event during which the eclogite was formed. The outer peripheral parts of the zircons, which have been modified by late‐stage fluids, give an age of 223±3 Ma. The granitic rock contains more zircons of anatectic origin found mostly in feldspar and quartz and usually also showing a similar composite texture. The inner main parts of the anatectic zircons with oscillatory zoning give a 206Pb/238U age of 727±15 Ma for the approximate age of the emplacement of the granitic rock, and their outer parts, an age of 219±3 Ma for a similar or even the same fluid event. It is thus suggested that the HP‐UHP metamorphism of the Bixiling eclogite facies rocks took place during the Neoproterozoic Jinningian, and the Indosinian age values may only represent a late event in the nature of fluid activity.
Control of Melt Structures on Cu–Au Mineralization in Basic‐Ultrabasic Complexes of Northern China
Authors: Wanming YUAN , Xuanxue MO 
Published: September 2010

AbstractBased on systematic analyses of 72 samples of different basic‐ultrabasic rocks, the present paper discusses the relationship between melt structure and Cu and Au mineralization. It is found that if the NBO/T, NBO, M2+, FeO and MgO values are relatively high and the T, M3+, Fe2O3 and CaO values are low the basic‐ultrabasic melt will be favourable to Cu (Ni) mineralization, but if the former are low and the latter are high it is favourable to Au metallization. Cu ions occupy dominantly octahedra in basic‐ultrabasic melt and the higher the NBO/T, NBO and M2+ values, the more the octahedra in the melt. Au element mainly takes the form of Au+ ions in basic‐ultrabasic melt and the Au+ ions constitute tetrahedral sites together with Fe3+ ions. Therefore, low M2+ and high Fe3+, i.e. high oxygen fugacity, can promote the enrichment of Au+ ions and Au mineralization. Components M+ (other than Au+), Al2O3 and SiO2 in basic‐ultrabasic melt have no effect on metallogenetic species. As mentioned above, in relevant diagrams distribution areas of the characteristic values of ore‐free melt and those of ore‐forming melt are overlapped in different degrees, which possibly indicates that not all the magmas have mineralizing ability. It can be well distinguished whether basic‐ultrabasic rocks are favourable to Cu or Au mineralization or they are just ore‐free rocks by analysing integrated diagrams of the characteristic values of the magmatic melt structure.
Geochronology and Geochemistry of the Middle Proterozoic Aoyougou Ophiolite in the North Qilian Mountains, Northwestern China
Authors: Zhaochong ZHANG , Jingwen MAO , Guochao ZUO , Jianmin YANG , ROBINSON Paul T. 
Published: September 2010

AbstractThe Aoyougou ophiolite lies in an early Palaeozoic orogenic belt of the western North Qilian Mountains, near the Aoyougou valley in Gansu Province, northwestern China. It consists of serpentinite, a cumulate sequence of gabbro and diorite, pillow and massive lavas, diabase and chert. Ages of 1840±2 Ma, 1783±2 Ma and 1784±2 Ma on three zircons from diabase, indicate an early Middle Proterozoic age. The diabases and basalts show light rare‐earth element enrichment and have relatively high TiO2 contents, characteristic of ocean island basalts. All of the lavas have low MgO, Cr, Ni contents and Mg numbers indicating a more evolved character. They are believed to have been derived from a more mafic parental magma by fractionation of olivine, Cr‐spinel and minor plagioclase. Based on the lava geochemistry and regional geology, the Aoyougou ophiolite was probably believed to have formed at a spreading centre in a small marginal basin. Subduction of the newly formed oceanic lithosphere in the Middle Proterozoic produced a trench‐arc‐basin system, which is preserved in the North Qilian Mountains.