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    20 April 2004, Volume 18 Issue 4
    Engineering Geology and Environmental Geology
    BASIN-MOUNTAIN COUPLING AND FORELAND BASIN PETROLEUM PLAY ANALYSIS
    LIU He-fu,LI Xiao-qing,LIU Li-qun ,Li Xiao-jun
    2004, 18(4):  389-403. 
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    Economic globalization leads naturally to the globalization of oil and gas exploration and development. On one hand, plate tectonic theory provides a solid base for hydrocarbon global exploration and development. On the other hand, the practice of hydrocarbon exploration and development in Asian and North American continental basins supplies a wealth of useful experience. According to a basin-mountain mechanical coupling scenario, there are three types of orogenic belts with their foreland basin counterparts:(1)oceanic subduction orogenic belts and retro-arc foreland basins;(2)continental collision orogenic belts and peripheral foreland basins; and (3)intracontinental orogenic belts and their associated foreland basins. There are two important guidelines for the exploration and development of foreland basin petroleum plays. Firstly, the deformations of the mountain front thrust belt and the foreland basin are spatially under the same strain conditions. Secondly, the pre-thrusting sedimentary sequence, the syn-thrusting sedimentary sequence, and the post-thrusting sedimentary sequence should be explored integrally.

    RESEARCH ON PRESENT STATUS AND VISTA OF GEODYNAMICS—AN OVERVIEW OF RESEARCH RESULTS IN THE 32nd INTERNATIONAL GEOLOGICAL CONGRESS
    LIU Shao-feng,CHEN San-you,ZHANG Hui-ping,SU San
    2004, 18(4):  404-414. 
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    The research results about geodynamics were shown in 11 sessions partitioned by regions and tectonism in the 32nd International Geological Congress. Through completely overview, the research results include: the tectonic evolution of Tethyan domains and the detailed processes of their rift, close and modification at later stages, supercontinents and their origin in Earth’s history, deep seated tectonics and metamorphism in subduction-collision belts, flat subduction in the Andes and its response of crustal deformation and magmatism, microstructural influence and control on dynamic process, melting and the rheology of the crust and upper mantle, and their significance for geodynamics, structure and evolution of  oceanic lithosphere, tectonics and reactivity of shield area, stable continental region earthquakes, space geodesy and present plate motion etc. These research results fully represent that the study of geodynamics is characterized by multi-subject, multi-means(for example, paleomagnetism, superdeep borehole, geophysics, geodesy and GPS),multi-scale(macroscopic, microscopic) and  multi-stage, complete, integrative, timing, positioning and quantitative exploration, and progressively probes into the evolution and dynamics of the earth (mainly lithosphere).

    PROGRESSES OF GEOMAGNETISM, PALEOMAGNETISM AND ENVIRONMENTAL MAGNETISM: AN OVERVIEW ON THE PRESENTATIONS IN THE 32nd INTERNATIONAL GEOLOGICAL CONGRESS
    2004, 18(4):  415-422. 
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    Regarding the theoretical research and applications of Geomagnetism, Paleomagnetism and Environmental Magnetism, over 120 absreacts were accepted by the 32nd inrenational geological cogress for oral or poster presentations. The principal contents are about:(1)Paleomagnetism applied in paleocontinental reconstruction, particularly in the study of assembly and breakup of the supercontinent Rodinia and Cenozoic tectonic evolution in the Mediterranean system;(2)Theory, observation and application of the geomagnetic polarity reversal and secular variation, magnetostratigraphy; (3) Magnetic susceptibility measurement applied in stratigraphic classification and correlation;(4) Magnetic evidence of climate changes at a millennial to Milankovitch time scale;(5) Environmental magnetism employed to identify anthropogenic pollution in sediments and soils. Together with other presentations associated with magnetic exploration, the magnetic methods show the strong potential in the global geological renaissance.

    SUMMARIZATION OF ADVANCES IN STRUCTURAL GEOLOGY IN THE 32ND INTERNATIONAL GEOLOGICAL CONGRESS
    WANG Gen-hou,HU Ling
    2004, 18(4):  423-428. 
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    The updated fruits in the structural geology and tectonics were brought forth in the 32nd International Geological Congress (IGC). Five aspects of these fruits could be summarized as follows:(1) Tectonics and sedimentation. This topic focused on the interrelation of tectonic processes and sedimentation in variable tectonic regimes, such as extensional and compressional tectonics. An important progress is the quantitative deformation inferred from the sedimentary sequence;(2) Structural styles of continental compression. Structural geologists paid more attention to the recognized styles, including thin-skinned, thick-skinned, simple shear and pure shear in the orogenic belt;(3)Tectonic inversion processes and structural inheritance in mountain belts. This describes the regional kinematic evolution after a sharp changing of the tectonic level;(4)Controls of continental margin structure in the formation of foreland thrust and fold belts with key to the basin-range coupling;(5)High strain zones and technological methods,including mapping,modeling, experiments and materials.

    ADVANCES IN REGIONAL GEOLOGY IN THE 32ND INTERNATONAL GEOLOGICAL CONGRESS
    ZHANG Da, WU Gan-guo
    2004, 18(4):  429-434. 
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    There are a whole series of recent achievements about regional geology presented in the 32nd International Geological Congress. A comparative study of PreCambrian period and younger orogens indicated that as reflected in structures within these areas, Central Europe has experienced a complex tectonic history during the Late Palaeozoic. These terranes were accreted along the margin of Baltica that was formed during the break-up of Rodinia. New data provide a more complete analysis on how the Afar plume and plate-scale tectonic events interacted the Red Sea Basin evolution. An intensive compressive structural stress field resulted from thrust existed in Caspian and Aral sea regions controlled the locations of oil, gas and deposites. Geochronology of Himalayan crystallines and oregenic evolution since Tertiary made great progress. Recent regional geological results in Alpine region are presented. The advances and actuality in North American and Caribbean area are reviewed during the congress.

    COEXISTING OF CONTRAST LITHOSPHERIC DEFORMATION AND MAGMATISM IN THE MEDITERRANEAN REGION: MANTLE FLOW AS THE RESPONSE AND EXPRESSION TO THE CONTINENT-CONTINENT COLLISION
    DENG Jin-fu,Martin F.J.Flower,SU Shang-guo,YU Xue-hui, LUO Zhao-hua
    2004, 18(4):  435-442. 
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    Based on the learning and understanding of the new data during the 32nd International Geological Congress and the Post-Congress field trio across the Apenninic-Maghrebian orogen in Sicily, this paper describes:(1)the coexisting of the striking contrast lithospheric deformation and magmatism in the Mediterranean region,(2)their synchronous migration with time, and suggests (3)a preliminary working model of the mantle flow during the continent-continent collional processes.

    ADVANCES IN OREGENIC BELTS AND OPHIOLITES IN THE 32ND INTERNATIONAL GEOLOGICAL CONGRESS
    ZHANG Da ,WU Gan-guo
    2004, 18(4):  443-448. 
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    There are a whole series of recent achievements about oregenic belts and ophiolites in the 32nd International Geological Congress. A comparative study of Archean and younger orogens lead to a conclusion that the key factor in determining these orogens’ overall geometries of Rodinia supra-continent about Mesoproterozoic assembly and Neoproterozoic breakup is further discussed. Oregenic process and possible model during late pre-Cambrian period and Paleozoic were ananlyzed. Deep exhumation, uplift and denudation of oregens are closely related to changes of weather and environment evolution, which is an important geological field. Igneous petrogenesis of ophiolites can not be explained by a simple model. It is studied that igneous petrogenesis of ophiolites are multi-genesis. Recent studies also set up several ophiolite emplacement models, such as bidivergent emplacement, domino-like rotation emplacement and subduction and rapid exhumation emplacement. Ophiolites occurred in Tethys and circum Pacific Ocean display obvious variety.

    KAMAFUGITES: A YOUNGER HOT TOPIC IN THE IGNEOUS PETROLOGY
    YU Xue-hui
    2004, 18(4):  449-453. 
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    The kamafugite is a rare type of ultra-potassic rocks, and a rock series contained generally that rock types of alnoite, olvine-melilitite, mafurite, katungite andwugangite and so on. The kamafugite and associated carbonatite contained abundant deep information from the Earth interior and is a younger hot topic in the igneous rocks. This paper presents simply the definition and classification of the ultra-potassic rocks, and petrological and geochemical characteristics of the kamafugites and carbonatites, according to the observation in the field and studies on the kamafugites and carbonatites from Italy and West Qinling, China, and also gives a simple review for the genesis and tectonic settings formed the kamafugites and carbonatites.

    ADVANCES IN MINERALIZATION ASSOCIATED WITH MAFIC-ULTRAMAFIC IGNEOUS ROCKS
    SU Shang-guo, DENG Jin-fu, TANG Zhong-li, LUO Zhao-hua, YU Xiao-yan, LI Fan-ning
    2004, 18(4):  454-459. 
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    Mineralization of Cu、Ni、Co、PGE、V、Ti、Cr、Fe are associated with mafic-ultramafic rocks. Why some mafic-ultramafic rocks bear deposits, and some not? The characteristics of primary magma, degree of partial melting, tectonic setting of mafic-ultramafic rocks, and an fault with long-term activity are the main controlling elements. In this paper there are some introductions to new mineralization processes of some famous deposits, for example, Bushveld Cu-Ni-PGE deposits. There are also some introductions to also new geophysical and geochemical methods to explore PGE deposits associated with mafic-ultramafic rocks.

    REVIEW ON ADVANCES IN ORE DEPOSITS AND RELATED SUBJECTS ON THE BASIS OF SUBMITTED ABSTRACTS OF THE 32nd IGC, FLORENCE, ITALY
    CUI Bin, BAI Guang-yu, GUO Hong-xia
    2004, 18(4):  460-462. 
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    Topics about developments of mineral deposits in the 32nd International Geological Congress are comprised of the following four parts: Mineral deposits associated with black shales; Mineral deposits and tectonics of central Asia; New developments in tin, tungsten and other rare metal deposits; Recent developments in marine minerals. This paper reviews these advances on ore deposits and related subjects.

    REVIEW AND EXPECTATION ON GEOCHEMISTRY ON THE BASIS OF SUBMITTED ABSTRACTS OF THE 32nd IGC, FLORENCE, ITALY
    CHEN Yue-long, TANG Jin-rong,Hou Qing-ye
    2004, 18(4):  463-486. 
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    The paper summarized systematically main geochemical advances related to genesis of life, surveillance on volcanic and seismic active areas, interaction between the crust and upper mantle at island arcs, mining and human production activities, interaction between water and rocks, surface processes of the earth, paleoclimatology and paleoenvironment as well as stable isotopic geochemistry, geochemical thermodynamics, organic geochemistry, analytical techniques of geochemistry on the basis of abstracts submitted to the 32nd International Geological Congress, Florence, Italy. The authors expect that geochemistry will act key roles on monitoring and predication of geological disasters, reclamation of polluted lands, synthetical programming of land use, origin and evolution of life and exploration of energetic and resource reservoirs for sustainable development. Geochemical data will be able to be gotten by accurate, sentitive instruments rapidly and economically through technological progress. Numeric and experimental simulations of geochemistry will make our recognition to geological process toward their realities under constraints of geochemical parameters.

    RECENT DEVELOPMENTS IN MINERAL MATERIALS SCIENCE-A SUMMARY OF THE 32nd INTERNATIONAL GEOLOGICAL CONGRESS
    LIAO Li-bing
    2004, 18(4):  487-492. 
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    Based on the analysis of the papers related to mineral materials science submitted to the 32nd International Geological Congress,recent developments in resource assessment of nonmetallic minerals and their beneficiation, modification and application of minerals, synthesis of minerals, synthesis of minerals, utilization of mine tailings and solid industrial wastes and utilization mechanism of minerals are summarized and compared to the 31st International Geological Congress. In view of the above analysis combined with the author’s understanding of the present situation of materials science, the trends of development in mineral materials science are presented.

    THE HOT POINTS AND TRENDS OF RESEARCH ON ANALYTIC TECHNOLOGY ACCORDING TO THE ABSTRACTS OF THE 32nd IGC, ITALY
    ZHAO Lei, TIAN Chuan
    2004, 18(4):  493-496. 
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    Authors discuss the general and special symposiuns in the 32nd IGC, read the abstracts about the introduction of analytic technology received in the congress. This paper intends to introduce the new trend that analytic technologies applied to Earth science, addressed some important instruments and suggests the related methods for testing on the basis of the abstracts of the congress. Authors give some thoughts to the analytic technology development.

    HE DUCTILE SHEAR DEFORMATION AND ITS TECTONIC BACKGROUND IN MIDDLE-PROTEROZOIC, CENTRAL INNER MONGOLIA
    CHEN Zhi-yong, ZHANG Hong, XU Li-quan, ZHANG Zhi-xiang
    2004, 18(4):  497-504. 
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    The characteristics of the ductile shear deformation developed between the Neoarchaeozoic Se’erdengshan Group, and Neoarchaeozoic to Paleoprozoic gneissic tonalite (the basement),and the Dulahala and Jianshan formation of the Baiyun’ebo Group, and the Shujigou and Zenglongchang formations of the Zha’ertaishan Group, Changcheng System ( the cover) are identical. The mylonitic foliations of the ductile deformation in this region strike nearly east-west, and dip to the north with the angle from 35°to 50°. The kinematic direction inferred from mineral stretching lineations shows that the cover slides to the north(northwest or northeast). The rock system of the basement at contact zone consists of mylonitic schist and mylonite; the lower part of the cover consists of mylonitic quartzite, mylonitic limestone, slate. Recumbent folds are developed in the quartzite of the Shuijigou and Dulahala formation, whereas boudinage and folding layer are developed in the slate and limestone from low amphibolite--high green-schist facies of the basement to low green-schist of the cover. It is shown by the characteristics of sedimentary, metamorphism and deformation that the Changcheng System of the Baiyun’ebo and Zha’ertaishan Group are the sediments of stable passive continental margin, and the ductile shear deformation developed in the Baiyun’ebo, Zha’ertaishan Group is a production of the same structural process in the same stage. The tectonic background of the ductile shear deformation is the extensional detachment of the Changcheng System. The deformation environment belongs to a lower temperature-pressure one, and the age when the ductile shear deformation began is in the end of the Changcheng period (1,400Ma). The ductile-shearing, upwarping and rifting in the Middle-Proterozoic in the middle part of Inner Mongolia were producted at different stages in one extensional tectonic event.

    FAULT SYSTEM AND TECTONIC STYLE OF THE YITONG GRABEN
    SUN Wan-jun, LIU Bao-zhu, LI Ben-cai, SONG Li-zhong
    2004, 18(4):  505-510. 
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    Strike-slip basins are commonly complex, mainly because of its complicated fault system and tectonic style. Based on systematic structural interpretation with 3D seismic data and analysis on regional geology and drilling data, the fault system and tectonic style of the Yitong Graben are studied. It is shown that the fault system of the Yitong Graben mainly composed of EW strike extensional normal faults and NE strike wrench faults, and reflects a right lateral strike-slip stress field. There are four evolution types of faults, and well matched with the basin formation and evolution. The main tectonic style of the graben is the “basement involved”, and is strike-slip and pull-apart origins, and can be subdivided into 5 types. There is only one dominant tectonic type in each fault depression. The difference of the tectonic styles is the main reason which causes each fault depression to have its own oil distribution law.

    GEOLOGIC AND GEOCHEMICAL CHARACTERISTICS OF VOLCANIC ROCKS IN SHIDUO, WESTERN GANGDISE, TIBET
    HUANG Gui-cheng, LI Zhi-chang, QIU Rui-zhao, Cai Zhi-yong
    2004, 18(4):  511-517. 
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    Shiduo volcanic rocks in the western segment of Gangdise, Tibet belong to high potassium calc-alkali series and calc-alkali series. They are divided into two stages of volcanicism:Paleocene(59.7Ma) and Miocene(17.2Ma). In time and position, the formor corresponds to Dianzhong Formation volcanic rocks of Linzizong Group in eastern Gangdise magmatic belt. Both of ∑REE(58.83x10-6)and degree of fractionation between LREE and HREE ((La/Yb)N=3.44 in the Paleocene volcanic rocks are much less than those in the Dianzhong Formation volcanic rocks. 143Nd/144Nd(0.512 275 to 0.512 420) and εNd(t)(-6.7 to -4.0) in the Paleocene volcanic are also smaller than those in the Dianzhong Formation volcanic rocks. These geochemical characteristics imply that volcanicism had some differences between western and eastern Gangdise magmatic belt in the same period. Based upon the Pb-Nd-Sr insotopes composition character and tectonic setting discrimination of trace element geochemistry, Shiduo volcanic rocks are formed in the environment of continental margin-arc-continental collision orogenic, and volcanicism orginated from the transitional process from the subduction of Neo-Tethyan oceanic plate to continental collision orogenics. Minerogenesis of Shiduo iron-copper deposit is related to Paleocene volcanism.

    GEOCHEMISTRY AND TECTONIC SETTING OF THE META-VOLCANIC ROCKS FROM DANFENG GROUP IN WESTERN QINLING
    YANG Gen-sheng. CHEN Yan-wen, HU Xiao-long
    2004, 18(4):  518-523. 
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    Taiyangsi gold polymetal deposit in Liangdang Country, western Qinling is a supper large gold deposit. Danfeng Group is a principle ore-bearing rock formation with gold, silver and lead-zinc mineralization. The volcanic rocks of Danfeng Group mainly consist of basalts and a few of andesite and rhyolite. The meta-basalt of Danfeng Group is characterized by high content in Al2O3 and low content in TiO2. The trace elements in the meta-basalt show the same characteristics as the island-arc tholeiite. The REE distribution patterns with high value of ∑REE,enrichment of LREE and incline to the right are similar to the island-arc tholeiit. The rock association, lithochemical and geochemical characteristics of Danfeng Group show its immature island-arc environment at Early Paleozoic. The large volcanic activities formed the primitive earth crust and the initial ore-source bed around the Taiyangsi area. The remobilization of ore-bearing hydrothermal solution formed further mineralization and enrichment in gold, silver, lead and zinc through the fractures and modification.

    ORIGIN OF ORE-FORMING FLUIDS OF THE XINQIAO Cu-Au DEPOSIT IN THE TONGLING MINERAL DISTRICT, ANHUI: EVIDENCE FROM He AND Ar ISOTOPES
    WANG Yan-bin,ZENG Pu-sheng,Li Yan-he,MENG Yi-feng,YANG Zhu-sen,
    2004, 18(4):  524-528. 
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    The ore genesis model of the Xinqiao Cu-Au deposit in Tongling of Anhui Province has long been in dispute, and the major debate focuses on whether the stratiform orebodies formed during the Yanshanian magmatic-hydrothermal event or they were products of carbonferious syn-sedimentary exhalative-hydrothermal event. The paper presents helium isotope data from fluid inclusions of five pyrites. The pyrites were collected from the stratiform orebodies in the deposit, and their 3He/4He ratios are significantly higher than 1, range from 1.2 to 1.22 Ra, which indicateds a mantle component in the responsible hydrothermal fluids. It is suggested that the ore-forming fluids were a mixture of deep circulating seawater and a mantle-derived fluids, which are similar to many of those modern submarine hydrothermal fluids. The data provide a new evidence that favor the submarine exhalative-hydrothermal origin for the stratiform mineralization in Xinqiao Cu-Au deposit.

    STUDY ON FLUID INCLUSIONS OF MOFANGGOU GOLD DEPOSITS IN PINGYI, WESTERN SHANGDONG
    2004, 18(4):  529-536. 
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    This paper studies in detail the characteristics of primary fluid inclusions and H, O isotope, which hosted in quartz, calcite and fluorite from alteration samples of Mofanggou and Lifanggou ore districts in Pingyi, western Shangdong. Research indicates that all inclusions, with similar size, shape and types, contain NaCl-H2O solution of vapor and liquid two phases. The temperature of homogenization of the fluid inclusions ranges from 120 to 450℃, and dominates by 120 to 260℃, with a bimodal distribution from 110 to 150℃ and 170 to 250℃. Temperature of gold mineralization ranges from 170 to 250℃. Ice-melting temperature varies from -2.8℃ to -11.5℃,corresponding to a range of salinities from 4.65% to 15.47% NaCl equivalent. δ34S values of pyrites in oredodies and wall rocks range from salinities from -0.71‰ to +2.99‰. δDSMOW and δ18DSMOW value in calcite and quartz vary from -63‰ to -70‰ and +18.4‰ to + 22.2‰, respectively. These data suggest that fluids originated from mantle and mixed with formation water during later mineralization.

    NEW INSIGHTS OF QUANTITATIVE ASSESSMENT TO FOUR DIMENSIONAL SPACE-TIME OF DEPOSITES-A CASE STUDY OF PORPHYRY Cu DEPOSIT IN THE YULONG AREA OF TIBER
    WANG Gong-wen, CHEN Jian-ping
    2004, 18(4):  537-542. 
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    Mineral exploration has stridden forward a new era of application of comprehensive ore-forming information to systematically quantitative search for buried large and super-large ore deposits with help of sophisticated techniques. The sophisticated survey, including 3S( GPS, GIS, RS) technology, dating technology and information processing techniques supply new support for mineral exploration. Based on the multi-information of porphyry Cu deposit in the Yulong area of eastern Tibiet, the forming and preservation of Cu deposit can be quantitatively evaluated through DEM (Digital Elevation Model) data processing and three dimensional simulation with 3S. The research result shows that ancient geography and ancient climate characters are favor to estimate the origination time of porphyry denudation; the denudation speed and the forming age of deposit are the important parameters to research deposit scale and conservation environment; the quantitative data of stratum, rock, structure and DEM are the important factors to evaluate ore-forming pattern.