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    A Discussion on the Adsorption Mechanism of Palygorskite Clay to Pollutants in Wastewater
    CHEN Tian-hu
    Abstract1507)      PDF (1467KB)(1364)       Save
    Palygorskite is a chain-layered silicate, with a a perture pass of 3.8 ×6.3A.It is gene?rally regarded that because this mineral has microapertur e pass and relatively larger specific surface area, the palygorskite clay is capable o f adsorbing the pollutants in wastewater. Based on the crystal structure of paly gorskite,its adsorption selectivity and our adsorption experiments, the present author holds the following opinion: because most molecules and hydrated ions hav e the diameters larger than that for the aperture pass of palygorskite, they u sually can not get into the aperture pass of palygorskite. Moreover, the inner ape rture pass of palygorskite preferentially adsorbs the water molecules. Terefore, in most cases during wastewater disposal processing the adsorption of palygorsk ite to pollutants is not an inner-surface adsorption, but an outer-surface ad sorption. This outer-surface adsorption is a kind of colloidal and ion exchange ad s orption. Besides the acidity of the solutions, the interaction of coexisting col loidal montmorillonite and palygorskite may play an important role in adsorption ability of palygorskite clay.
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    Chloritization of Qitianling Granite Related to Bailashui Tin Deposit,Southern Hunan Province
    ZHAO Zhan-jie, LU Jian-jun, YAO Yuan, ZHANG Rong-qing, GUO Wei-min, ZHANG Huai-f
    J4    2011, 17 (4): 531-545.  
    Abstract1919)      PDF (5927KB)(1867)       Save

    The Bailashui tin deposit is located in Qitianling Yanshanian biotite granite, Southern Hunan province. Chloritization
    is a universal hydrothermal alteration in this ore-bearing granite. Based on the research of the samples collected from the
    drillhole, we found a notable variation in the chloritized degree of the granite. This study was carried out by selecting three groups
    of granite samples which displayed notable different degree of chloritization. The chloritization nhich closely related to oreforming
    in the Sn-bearing granite had been discussed. The results indicated that, in the granite samples of different degrees of
    chloritization the petrography and chemical composition of chlorite changed with a series of obviously variable characteristics.
    According to the analysis of micropetrography and relevant geochemical data, some conclusions could be drew as follows. Themetasomatic sequence of rock-forming minerals in the granite replaced by chlorite is: amphibole and biotite→plagioclase and
    potassium feldspar→quartz. The variable shape of chlorite was, on the one hand, related to the composition of chlorite; on the
    other hand, related to the crystal texture of rock-forming minerals which were replaced by chlorite. As the chloritization of granite
    was stronger, the LOI and Zn content of whole-rock samples would be higher, and the Cl contents losing to hydrothermal liquid
    from original rock would be more. With the chloritized degree of granite becoming stronger, main compositions of chlorites would
    present regular variations. The Si content of chlorite decreased in the process of chloritization. Al elements were released after
    the breakdown and dissolution of feldspar. The mobilization and redistribution of Al on the thin-section scale increased the
    aluminum content of chlorite. Fe element were brought in to the chrorite by hydrotherm. The amounts of chlorite formed depended
    on how much Fe had been introduced into the hydrothermal system. The Mg for the formation of chlorite was primarily related to
    the redistribution of Mg which was released from mafic minerals. Mn element was mainly brought in to the chlorite by the outer


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    A Microanalysis Study on Monazite Composition Distribution
    HONG Wen-xing1, ZHU Xiang-kun2
    Abstract1316)      PDF (1223KB)(844)       Save
    The monazite samples of various genetic types are taken fro m different localities in China and have been analysed by EPMA. The available analytical data show that the monazites of magmatic granite and pegmatite have l ower contents of La (4%~13%), Ce (18%~28%) and higher contents of Sm (2% ~5%), Gd (1%~3%), Y (1%~3%), Th (3%~7%). The monazite of hydrothermal metasomatic origin has higher contents of La (12%~18%), Ce (>28%), and lowe r contents of Gd (<0.3%), Th (0.1%~0.3%) and Y (0.06%~0.14%). The composi tional change profiles of monazite demonstrate a heterogeneous distribution of e lements La, Ce, Nd, P, Th, Si, Ca and U. This was caused by the differences in geological environments, temperatures, pressures and compositions of the hy drothermal solutions.
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    DistributionSummaryofCenozoic Basalts in CentralandEasternChina
    CHEN Xiayu, CHEN Lihui*, CHEN Yang, ZENG Gang, LIU Jianqiang
    J4    2014, 20 (4): 507-.  
    Abstract1425)      PDF (4273KB)(2323)       Save

    Abstract:Distribution information of Cenozoic basalts were extracted by pixel from the geological map of central and Eastern China,
    and overlaid on the high-precision geomorphologic map, utilizing a digital-rimage processing program. Based on this method, we
    estimated the total and sub-regional area of Cenozoic basalts exposed in Central and Eastern China. The main observations include:(1)
    The total area of Cenozoic basalts in Central and Eastern China is 78 525 km2. (2) The area of Cenozoic basalts in Central China is
    35 487 km2, while that in Eastern China is 43 038 km2, with a ratio of 45∶55. (3) The area of Cenozoic basalts increases along with
    younger age, and the ratio of which from Paleogene, Neogene, to Quaternary is 0.36∶21.65∶77.99. (4) Cenozoic basalts of Central China
    are mainly distributed in the north. Three main regions include: Great Xing'an Range, Xilin Gol region and northern edge of North
    China, with an area of 7334 km2, 13 843 km2, and 14 310 km2, respectively. (5) In Eastern China, Cenozoic basalts are more widely
    distributed, from Heilongjiang province in the north to Hainan Island in the south, and they can be divided into three regions: Northeast
    China to the east Songliao basin (33 324 km2), Eastern China including Shandong, Zhejiang, Jiangsu and Fujian provinces (1 707 km2),
    and Leiqiong region including Hainan Island and Leizhou Peninsula (8 007 km2). (6) Taken Shandong province as the boundary,
    Cenozoic basalts in Central and Eastern China are mainly distributed in the north with an area of 69 191 km2, while that of the southern
    part is 9334 km2, and their ratio is 88∶12.

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    Application of Small Baseline Subsets D-InSAR Technology to Estimate the Time Series of Land Subsidence
    WANG Yanxia, SHI Zhaoliang, CAO Min, LIU Bo
    J4    2014, 20 (2): 333-.  
    Abstract664)      PDF (3259KB)(1055)       Save
    At present, the geological disasters of ground subsidence occur in many cities of China, which are particularly severe in the Yangtze River Delta region where subsidence has long duration, large-scale causing huge economic losses. Wuxi is one of the typical cities of the large-scale land subsidence in Yangtze River Delta. In this article, we use ten ALOS PALSAR images, the time series of land subsidence of Wuxi city from January 12, 2007 to March 10, 2011 is estimated using the small baseline subsets D-InSAR technology. The results show that obvious subsidence occurred in the Hui Shan area, and the settlement in other areas is relatively stable with the average settlement about 15 mm; The settlement spatial pattern changed during 2007-2009, but the settlement rate increased from 2009 to 2010. Experiments prove that the short baseline subset (SBAS) interference in long time series of large-scale subsidence monitoring is feasible and effective. The results of monitoring ground subsidence provide an important scientific basis for disaster prevention and mitigation, and enable policy makers to make the right decisions. In the meantime, we can also trace the history of engineering activities according to the subsidence.
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    Zeng Lian-buo1, Gao Shao-qing2
    Abstract1116)      PDF (1425KB)(880)       Save
    Based on the core description and three-dimensional finite-element numerical simulation, the authors comprehensively evaluated the distribution characteristics, development rule and effect on exploitation of different fracture groups. There are four group fractures which were controlled by sedimentary microfacies and structure in Daan oil field. Under the effect of modern stress field, the permeability of the EW fracture is the best, then the NW and NE fractures, the NS fracture is the worst. The mudstone partings absorb water seriously and have important influence on exploitation effect because both hig-dip tectonic fracture and low-dip bedding detachment fracture are developed wel1.
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    A Study on the Feasibility of Ground Freezing Method in Nanjing Metro Engineering
    JIANG Huang1, L1 Xiao-zhao2, YOU Sheng-wu3
    Abstract1360)      PDF (2076KB)(1104)       Save
    The authors summarized the application of artificial ground freezing method (AGFM) to geotechnical engineering at home and abroad. Although AGFM has been used in mining shaft construction for over 100 years at abroad and over 40 years in China, its application in other geotechnical engineering is still in its beginning stage. Nanjing Metro will be built in a complicated and adverse geoenvironment, facing a series problems as the alternation of rockmass with soft soils, surface water, pore water in ancient buried river, karst water and fault water etc. Alternation of rockmass with soils makes the excavation hard in Shield Method and is difficult proof water and support in current NATM. Therefore, the authors suggest AGFM, and discuss its feasibility, design method and technical key points taking Zhu-Gu section (from Zhujiang road station to Gulou station) as an example. Considering the unfavorable factors, which will be encountered in urban underground freezing engineering, we suggest that higher safety coefficient should be used in the ice wall design according to Lamé's formular. The authors also believe that the following environmental problems arising from AGFM deserve particular attention: weakening of mechanical properties of soil in freezing-thawing cycle, freezing expansion and thawing collapse, additive stress on subject structure arising from the freezing-thawing process and frost defect to concrete of underground structure. From engineering analogy, it can be concluded that freezing expansion and thawing collapse in the Zhu-Gu section can be limited by building protection of effective engineering countermeasures.
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    Microbial Bioremediation of Metal-and Radionuclide-Contaminated Soils and Groundwater
    Ye Qi 1 2, Zhan Chuan-lun1 2
    Abstract1209)      PDF (2489KB)(912)       Save
    Contamination of environments by heavy metals and radionuclides has become a serious problem worldwide.The treatment of heavy metals and radionuclides in environments by specific microorganisms such as meta1-reducing and metal-resistant bacteria has become promising technology.The successful application of in-situ bioremediation will provide potential ways to clean up heavy metals and radionuclides in contaminated environments.Recent studies also focus on understanding the effect of heavy metals and radionuclides on the microorganisms in the microbial community.Microbial mats and biofilms are two representative microbial communities functioning in bioremediation.Metal speciation and valence variation, transport processes,and microbial metabolism are three important ingredients for metal and radionuclide remediation.Combining these ingredients enables us to better understand the relationships between the naturally occurring microorganisms and bioremediation processes.
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    Effects of Air Exposed Coal Fly Ash on Groundwater Contamination
    J4    2013, 19 (4): 683-.  
    Abstract745)      PDF (1921KB)(1206)       Save
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    New Ideas on the Origins of Potash Deposits in Yunnan China and Laos
    LI Minghui,YAN Maodu,FANG Xiaomin,ZHANG Zengjie,SUN Shurui
    J4    2016, 22 (1): 60-.   DOI: 10.16108/j.issn1006-7493.
    Abstract868)      PDF (868KB)(829)       Save

    The Lanping-Simao basin in the southwestern China is located at the junction of the Eurasian and Indian Plates, and
    adjacent to a large potash deposit of Khorat Basin and Sakon Nakhon Basin in Thailand and Laos. Chinese scientists thought that the
    potash deposit in Lanping-Simao basin should be as large or important as that in Khorat Basin and Sakon Nakhon Basin. The
    relationship between Mengyejing potash in Lanping-Simao basin and potash deposits in the Sakon Nakhon Basin and Khorat Basins has
    long been discussed in many respects such as tectonic belt, depositional features, salt minerals, geochemical elements, and forming era.
    Many scientists thought that they had similar brine origins, and hydrothermal fluid was one important origin for the potash deposit.
    However, the ideas have received no supporting evidence. The type of hydrothermal fluid was not clear either. This study presents δ18O
    and δD of halite inclusions from a ZK2893 core in Laos to provide isotopic evidence for the idea. The values of δ18O are from -2.3 to
    9.5‰ with an average of 2.9‰ , while those of δD are from -78 to -150‰ with an average of -108.6‰ . Most of δD was less
    than -90‰. The relationship between δ18O and δD shows that the hydrothermal fluid is metasomatic hydrothermal fluid which was
    originated from reactions between rainwater and surrounding rocks. Surrounding rocks are important origin for potash deposits. Most
    data were plotted near to the 150℃-curve in the δ18O-δD diagram. The possible forming temperature of halite inclusion in Laos could be

    about 150℃. On the other hand, the forming temperature of halite inclusion in Lanping-Simao Basin was about 145℃ with the highest
    value of 170℃. The similar temperatures provide new evidence for their similar brine origins of the two basins.

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    Influence of Biodegradation on Light Hydrocarbon Parameters in Crude Oil of Kuqa Formation from Dawanqi Oilfield
    YANG Lu, LI Meijun*, ZHANG Chunming
    J4    2016, 22 (3): 549-.  
    Abstract384)      PDF (620KB)(902)       Save

    Oil samples from Dawanqi Oilfield in the Tarim Basin, NW China, that have been biodegraded to various degrees were
    analyzed to study the effect of biodegradation on light hydrocarbons. The results show that biodegradation led to preferential depletion
    of n-alkanes, followed by iso-alkanes and cycloalkanes, which results in variations in the corresponding C6 and C7 ternary diagram. With
    increasing biodegradation, the values of n-heptane and isoheptane decrease, ratios of toluene/n-heptane and benzene/n-hexane increase,
    and n-heptane/methylcyclohexane ratio decreases. In Dawanqi Oilfield, the crude oil with heptane values of 0~21 and isoheptane
    values of 0~2.6, is categorized as“Biodegraded”zone. The graph of toluene/n-heptane versus n-heptane/methylcyclohexane indicates
    that secondary alterations should be applied with caution in slightly biodegraded crude oil.

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    Influence of Magmatic Intrusion on the Distrbution of REE in Coals at Western Huagou, Huaibei
    J4    2013, 19 (4): 671-.  
    Abstract635)      PDF (551KB)(983)       Save
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    An Estimation of Hot-Dry-Rock (HDR) Resources in Jiangsu Province
    XU Li , WANG Liangshu, YANG Qian
    J4    2014, 20 (3): 464-.  
    Abstract644)      PDF (589KB)(1355)       Save

    As a clean renewable geothermal resource, the hot-dry-rock has been more and more maturely utilized because of its
    obviously increasing values. The extensive volcanic activities and upwelling flow of deep-seated thermal energy in Jiangsu Province
    during the Mesozoic and Cenozoic time provided abundant hot-dry-rock storage. Based on an analysis of the heat flow, rock thermal conductivity at different depths, radioactive heat generation, and the temperatures at different depths in Jiangsu Province are calculated using the contribution rate of the superposition method. The calculated results are compared to the data from thermal gradient method in 5~8 km, eventually the hot-dry-rock resource amount at the depth of 3~8 km in Jiangsu Province is estimated by means of the volume method. The results show that the resource amount at the depth of 3~8 km could reach 2.18×1021 J, which is equivalent to the heat of 7.49 billion tons of standard coal. On the basis of 2% of the exploitable rate, the resource is estimated to be half of the current total energy consumption of Jiangsu Province in a year (about 0.15 billion tons of standard coal), thus demonstrating a promising potential for utilization.

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    Major Elements Characters of the Middle Pleistocene Vermicular Red Clay from the Western Sichuan Plain
    Ying Lichao, Liang Bing, Wang Quanwei, Zhu Bing, Hao Xuefeng, Wang Xin, Liu Lian
    J4    2012, 18 (4): 759-.  
    Abstract1216)      PDF (541KB)(1209)       Save
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    CharacteristicsoftheLateTriassicDeep-waterSlopeBreakBeltin SouthwesternOrdosBasinandItsControlonSandbodies
    LIU Fen,ZHU Xiaomin*,LI Yang,XU Liming,ZHU Shifa,XUE Mengge
    J4    2015, 21 (4): 674-.  
    Abstract1232)      PDF (3827KB)(1179)       Save

    DuringtheLateTriassic,theslopebreakbeltofdepressionlakebasinwasdevelopedintheOrdosBasin.Basedontherock types,faciesassociations,andseismicreflectioncharacters,thedeep-waterslopebreakbeltswererecognizedinthesouthwesternand northeasternpartofthelakebasin,whichwerenamedasthesouthwestslopebreakbeltandthenortheastslopebreakbeltaccordingly. Theterrainslopewascalculatedwiththerateofformationthicknesschange,andthustheslopebreakpointswereorientatedtoidentify thedistributionofslopebreakbeltsduringtheChang7-Chang6period.Thesouthwesternslopebreakbeltisoflargescale,whilethe northeasternoneissmaller.Theslopebreakbeltsobviouslyhavecontrolsonsandbodies,mainlyreflectedinthreeaspects:origin types,thicknessvariations,anddistributionalmorphology.Uponthedeep-waterslopebreaks,sandbodiesofdeltafrontweredeveloped. However,underthedeep-waterslopebreaks,sandbodieswereformedmostlybygravityflows,suchassublacustrinefanandslump olistolith.Meanwhile,differenttypesofgravityflowssandbodiesdevelopedinsteepslopebeltandgentleslopebelt.Thethicknessofsandbodiesfromthesameprovenancedecreasedfirstlyandthenincreasedfromtheupperslopebreakbelttotheslopetoe.Uponthe slopebreakbelt,sandbodiesoccurinstripsorasasheet.Undertheslopebreakbelt,theirpatternsvariedaccordingtotheterrainslope andthedistancetotheslopetoe.

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    TraceandRareEarthElementsandSulfurIsotopeAnalysisofBarite DepositsinWestHunanandEastGuizhou
    SUN Zehang, HU Kai, HAN Shanchu, Liu Yin
    J4    2015, 21 (4): 701-.  
    Abstract1149)      PDF (837KB)(916)       Save

    ThebaritedepositsformedintheearlyCambrianinXinhuangandTianzhuarethelargestbaritedepositintheworldandare representativeintheglobalscope.Thisstudycarriedouttherareearthelementsandsulfurisotopeanalysesofthesebaritedeposits.All thesample'sV/CrandU/ThvaluesandtheCenegativeanomalyimpliedthatthedepositswereformedinanaerobicandreduction environment.TherareearthelementsofbaritehaveobviouslyEuelementpositiveanomaly,indicatingthattheore-formingprocesswas stronglyaffectedbytheseafloorhydrothemalfluidandthesourceofthebariumismainlyfromtheseafloorhydrothemalmaterial;The sulfurisotopecompositionofBaSO4mainlyrangedfrom+40‰to+45‰,enrichedin34SandthesulfurisotopeofBaSO4ischaracterized bytowerstyledistribution,whichindicatesthatthesourceofsulfurisofsingle-sourceandfromtheseawatersulfate.Theδ34Sofpyrite islowerthantheδ34Softhecontemporaryseawater,indicatingthatbiologicalbacteriaplayedanimportantroleinthesulfatereduction intheseawaterandimplythatthebaritedepositformedinanenvironmentwherethereislimitedseawaterexchange.Basedontheaboveanalysis,thebaritedepositwasformedinasemiclosed-closedlagoonalandanaerobicenvironmentwheretherearefrequent seafloorhydrothermalactivities.

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    YUAN Xiao-qi1, MIN Qi1, YANG Jun-jie1, GUO Zhong-ming1, LIU Guan-bang2
    Abstract1325)      PDF (988KB)(806)       Save
    Piece of pottery had not been found previously from the sediments of 10000 years old in China and abroad.During a research of the Quaternary stratigraphy in Qingyang district, Gansu Province, some pieces of pottery have been discovered from the upper silty clay layer and basal gravel bed of the Salawusu Formation.In the some horizon, many mammalian fossils and human cultural remains, such as the palaeoliths, ashes and charcoal bits, have also been found.Among the mammalian fossils are such taxa as Palaeolarodon naumanni, Coelodonta antiquitatis, Eqnns prsewalskyi, Crocuta ultima, Megaloceros ordosianus, Spirocerus kiakhtensis, Ovis ammon, Bos primigenius etc., which are typical for the Late Pleistocene.14 C dating for the calcareous nodule of the upper part of Salawusu Formation at Shilipodi of Jiaozichuan in Qingyang suggests a age about 25 290±500aB.P.,which is consistent with the geological age indicated by the mammalian fossils.Therefore, the age of these Pieces of pottery discovered in the Salawusu Formation should also be the Late Pleistocene.The new discovery suggests that the history of human pottery-making could be further traced back from about 10 000 years ago to about 30 000 years ago.
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    REE Geochemistry of Each Metallogenic Series in Laojunshan Tin Poly-metallic Metallogenic Region,Southeastern Yunnan Province, China
    JIA Fuju, NIAN Hongliang, LI Xing, WU Wei, YAN Yongfeng, LIU Xiaowei, GUO Yuejin
    J4    2014, 20 (4): 549-.  
    Abstract1056)      PDF (787KB)(1488)       Save

    This paper focuses on the Laojunshan tin poly-metallic metallogenic region and studies the geological processes related to
    ore forming processes such as volcaniclastic sedimentation in early Caledonian, regional metamorphism in Indo-China period,
    superimposed late Yanshanian granitic process magmatism. Three types of metallogenic series were recognized, and each kind of
    metallogenic series has different REE distribution patterns. Type Ⅰ. Volcaniclastic sedimentation in early Caledonian-regional
    metamorphism in Indo-China period metallogenic series in the northeastern part of the study area have the similar REE distribution
    patterns with marine extrusive-sedimentation rocks (island-arc tholeiite type). Type Ⅱ. Volcaniclastic sedimentation in early
    Caledonian-regional metamorphism in Indo-Chinese epoch metallogenic series, near the granite contact zones, the REE distribution
    patterns show the coexistence of marine extrusive-sedimentation rocks and granites. Type Ⅲ. Superimposed granitic metallogenic

    series of the late Yanshanian epoch have the similar REE distribution patterns with those of granites.

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    Raman Spectroscopic Characteristics of Different Hydrocarbon-Forming Organisms
    Bao Fang, Tenger , Yang Yunfeng, Xie Xiaomin, Zhang Meizhen, Wang Rucheng
    J4    2012, 18 (1): 174-179.  
    Abstract1276)      PDF (998KB)(2058)       Save

           This study proposed a method to distinguish the bio-precursors of organic matter in hydrocarbon source rocks. Through
    analysis of the Raman spectra of two common types of organisms, phytoplankton and benthic algae, in hydrocarbon source rocks, we found that the organic matter originated from different organisms have different Raman spectra characteristics. The difference in Raman shift between G-mode peak and D-mode peak normally indicates the polymerization degree of aromatic structures, and the intensity ratio of D-mode peak to G-mode peak reflects the order degree of aromatic structures. By comparing the spectra parameters of different hydrocarbon-forming organisms, we found that the polymerization degrees of the macerals originated from benthic algae are greater than those of phytoplankton as well as the order degree of phytoplankton is also greater than benthic algae. Our research shows that the difference in Raman shift between G-mode peak and D-mode peak of different hydrocarbon organisms sampled from the same layer displays significant difference. The polymerization degree of aromatic structure of organic matter can be detected by Raman spectroscopy to distinguish different organisms. Although the intensity ratio of D-mode peak to G-mode peak is not only subject to the thermal maturity of materials but also sensitive to their structure properties of bio-precursor organism, it may also serve as a reference for distinguishing different hydrocarbon-forming organisms in practice.

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    ZirconU-PbAgesandGeochemicalCompositionofthePolunshan PlutonintheTenchongBlock,WesternYunnan
    WU Jiade, WANG Yan, XIE Qinglu, QI Yue, LI Junhui, HE Jianfeng, CHEN Fukun
    J4    2015, 21 (3): 508-.  
    Abstract1022)      PDF (1200KB)(742)       Save

     Mesozoic to Cenozoic magmatic activities, widely distributed in the Tethyan belt of western Yunnan, are induced by the long-time complicated orogenic processes. Zircon U-Pb age data and geochemical characteristics of the Polunshan granite, exposed in the Tenchong block, are reported in this study. The Polunshan granite pluton is composed mainly of porphyritic coarse-grained granodiorites. Geochemically, this granite is characterized by high alkali contents and belongs to the high-potassic calc-alkaline rock type. It enriches in large-ion lithosphile elements and depletes in high field-strength elements (Nb, Ta, Ti and P). Results of the zircon U-Pb dating suggest emplacement ages of 66~63 Ma for the magma(s) of the Polunshan granite, pointing to a magmatic product related to the closure of the Neo-Tethys Ocean. Many analysed zircon grains or crystal domains have high contents of U and Th. They yield U-Pb ages of about 35~30 Ma, significantly younger than emplacement time of the granite, but similar to the age of deformation or metamorphism of the Gaoligongshan metamorphic belt. This phanomenon implies that the U-Pb isotopic system of those zircons of high Th-U-contents was reset during the late thermal event. The Polunshan granite exhibits entrenchment feature in Sr-Nd isotopic composition, with initial 87Sr/86Srratios of 0.7158 to 0.7164 and initial εNd values of -14.5 to -15.3, corresponding to Nd modal ages of 2.04~2.10 Ga, suggesting that Paleoproterozoic crustal material as a major source of the magma(s).

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    Migration Pathway System of the Reservoir in Shawan Formation in Chepaizi Salient, Junggar Basin
    WANG Kun, REN Xincheng, MA Kui, HUANG Qingyu, SHI Shuyuan, GAO Jianwen
    J4    2016, 22 (2): 350-.  
    Abstract387)      PDF (2239KB)(785)       Save

    The Neogene Shawan formation is one of the important hydrocarbon-rich strata in Chepaizi salient. Based on the analysis of
    reservoir distribution and oil nature, coupled with results of previous studies, the accumulation process of Shawan hydrocarbon is
    divided into two stages: paleoreservoir stage and secondary adjustment stage. The migration pathway systems and their spatial
    combinations are discussed. In the paleoreservoir stage, the Cretaceous basal unconformity and syngenetic reverse faults composed the migration pathway in the Hongche fault zone formed system. The effective thickness of migration zone in the unconformity is thicker in the northern and estern part of the research area while pinching out toward the west; syngenetic reverse faults controlling the formation and development of Hongche fault zone have large fault displacements and beneficial for hydrocarbon migration. In the secondary adjustment stage, sandstone in the first member of Shawan Formation (N1s), epigenetic normal faults in Hongche fault zone, Aika fault zone and Neogene normal fault in Chepaizi salient formed the migration pathway system, the N1s sandstone salient with continuous and stable deposition distributes in the Chepaizi, blanket-like pinching out from the south to the north. As the lowest sandstone bed, the blanket-liked sandstone is the most important transverse migration bed in this stage. Large-scale normal faults in the Hongche fault zone were developed in the late Neogene; Normal faults in the Chepaizi salient were also developed in the same period; the Aika fault zone continued to be active in the Neogene, all of which formed the vertical migration pathway system in the secondary adjustment stage. The dominant migration zones of the Cretaceous unconformity and blanket-liked sandstone migration beds are predicted using
    migration pathway index (MPI) and Quantitative Grain Fluorescence (QGF). In the plane, area with MPI greater than 0.3 is regarded as
    the dominant migration zone of unconformity migration bed and the area with QGF greater than 3.8 is regarded as the dominant
    migration zone of N1s blanket-like sandstone. Based on the analysis of spatial combination of migration pathway systems in different
    stages and the relationship between hydrocarbon distribution and migration pathway systems, the control action of migration pathway
    system on hydrocarbon accumulation is confirmed prospecting to have. The well P609 area is predicted to have advantages of
    hydrocarbon migration, which can be regard as the exploration target of further prospecting.

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    Organic Carbon Isotope Stratigraphy of the Early Cambrian Huitong Section in Hunan Province, Southeastern Yangtze, China
    WANG Dan, LING Hongfei*, ULRICH Struck, YAO Suping, LI Da, WEI Wei, WEI Guangyi
    J4    2016, 22 (2): 274-.  
    Abstract385)            Save

    The early Cambrian is one of the critical periods during Earth evolution involving significant evolution of marine
    environment and metazoans. However, the early Cambrian strata in the deep-water setting along the southeastern margin of the Yangtze Platform are still lack of systematically and accurately stratigraphic correlations. Here we conduct a high-resolution organic carbon isotope chemostratigraphy of the deep-water chert in the Liuchapo Formation and black shales in the Xiaoyanxi Formation, which werecollected from drill cores in the Huitong section of Hunan Province. Results indicate four positive δ13Corg excursions (termed P1, P2, P3 and P4 ) and two negative δ13Corg excursions (termed N1 and N2 ) in ascending order. Combined with the fossil records and zircon U-Pb dating data, we correlate the δ13Corg curve of the Huitong section with the δ13Corg and δ13Ccarb curves of other sections in Hunan and shallow-water areas including Yunnan and Three Gorges. The correlation implies that the Ediacaran-Cambrian boundary was placed at the negative δ13Corg excursion (Basal Cambrian Carbon isotope Excursion, BACE) in the upper Liuchapo Formation of Hunan Province. This negative δ13Corg excursion (BACE), however, has not been identified at the Huitong section, owning to the limited drill core depth.
    The three positive δ13Corg excursions P1, P2 and P3 can be correlated with ZHUCE (ZHUjiaqing Carbon isotope Excursion, Stage 2),
    CARE (Cambrian Arthropod Radiation isotope Excursion, Stage 3) and MICE (Mingxinsi Carbon Isotope Excursion, Stage 4) δ13Corg
    excursions, respectively. In contrast, the two negative δ13Corg excursions N1 and N2 are likely correlated with SHICE (SHIyantou Carbon
    isotope Excursion, Stage 2) and AECE (Archaeocyathid Extinction Carbon isotope Excursion, Stage 4) δ13Corg excursions, respectively.
    Therefore, the upper Liuchapo and the basal Xiaoyanxi formations probably belong to the Cambrian Stage 2. The lower Xiaoyanxi
    Formation belongs to the Cambrian Stage 3 and the middle-upper Xiaoyanxi Formation belongs to the Cambrian Stage 4. However, it is
    still unclear whether the top of the Xiaoyanxi Formation covers the end of the Cambrian Stage 4. The negative δ13Corg excursions
    probably result from the transportation of 12C-enriched anoxic bottom water through upwelling from deep to shallow water, and might be
    faunacouldincreasetheprimaryproductivityandassociatedrateoforganicmatterburial,whichleadtothepositiveδ13Corg excursions.

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    PerformanceandMechanismsfortheRemovalofCopperIonsfrom AqueousSolutionsbyClayeyDolomite
    QIU Gao, XIE Qiaoqin, CHEN Tianhu*, LIU Haibo, XIE Jingjing, LI Hongwei, TIAN Yi
    J4    2015, 21 (4): 616-.  
    Abstract1421)      PDF (626KB)(5877)       Save

     In comparison to common dolomite and palygorskite clay, the effects of parameters such as pH, contact time, initial concentrationofcopperonremovalofcopperionsusingclayeydolomiteinpalygorskiteclaydepositwasinvestigatedusingstatic adsorptionexperiments.Thekineticsofcopperremovalwasdiscussedbythepseudo-first-order,thepseudo-second-orderandthe Elovichmodel,andthesorptionisothermwasanalyzedbyLangmuirandFreundlichisothermequations.Theresultsshowthatthe effectofpHontheremovalofcopper(II)ionbyclayeydolomitewaslessthantheothertwo.Morethan85%ofcopper(II)ionswere removedinthepHrangeof3to5andtheoptimumpHis5.Thekineticdataoftheremovalofcopperbyclayeydolomitefittedthe pseudo-second-orderkineticmodelverywell.Theremovalrateaswellastheefficiencywasthehighest.Theisothermdatacanbe described by the Freundlich model and the removal capacity was 186.2×10-3. The removal mechanisms were mainly surface precipitationinducedbythemineral-waterinteractionsandelectrostaticattractionbetweenpalygorskiteandthenewlyformedcolloid [Cu2CO3(OH)2].Thepresentstudyconcludesthatclayeydolomiteismoreeffectivebecauseoftheintergrowthofnanoscalepalygorskite andsub-micronporousdolomite,leadingtothehigh-efficientremovalofcopperionsthanthecommondolomiteandpalygorskiteclay, anditpossessesthepotentialfortreatingcopperwastewater.

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    ThePhaseTransitionofPyriteThermalDecomposition inNitrogenGas
    SHI Yadan, CHEN Tianhu, LI Ping, ZHU Xiao, YANG Yan
    J4    2015, 21 (4): 577-.  
    Abstract1520)      PDF (714KB)(1938)       Save

     The phase transition of pyrite to monoclinic pyrrhotite and monoclinic pyrrhotite to hexagonal pyrrhotite in the nitrogen atmosphere has been investigated. The study was performed using differential thermal analysis and thermo-gravimetric analyzer (DTA-TGA), X-ray powder diffractometer (XRD) and magnetic susceptibility meter. The decomposition of pyrite begins at the temperature of about 400℃. At the temperature below 500℃, there is no phase change. As temperature increases to 500-600℃, pyrite phase begins to transform to monoclinic pyrrhotite and the transformation rate rises as the temperature rises. And the magnetic susceptibility is also higher as a result of the existence of monoclinic pyrrhotite. The rate of pyrite transformation to monoclinic pyrrhotite is higher than the rate of monoclinic pyrrhotite transformation to hexagonal pyrrhotite. With the temperature elevating, the two rates increase as well. When the temperature is higher than 600℃, hexagonal pyrrhotite, even troilite (FeS), is the primary product. The rate of pyrite transformation to monoclinic pyrrhotite is lower than the rate of monoclinic pyrrhotite transformation to hexagonal pyrrhotite.

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    Evaluation on Potential Carbon Sequestration Capability of Typical Mafic Tailings in Eastern China
    WANG Xiaoyan, ZHANG Lijun, YUAN Xuyin, LIU Lianwen, JI Junfeng
    J4    2012, 18 (2): 248-.  
    Abstract1355)      PDF (1153KB)(1193)       Save

           The carbon sequestration by interaction of mafic tailings with CO2 to form a stable carbonate minerals is a new and
    promising method for reducing CO2 emission. The evaluation of CO2 sequestration potential of mafic tailings is the essential premise for the reasonable utilization of these tailings. This paper mainly aims at 10 tailings in two typical ultrabasic rock belts (Donghai-Rizhao rock belt and Chicheng-Chaoyang rock belt) of eastern China, and analyzes mineral components, size distributions and major elements of tailing samples. Then a comprehensive evaluation about the carbon sequestration potential is taken for these mafic tailings in the two rock belts based on analysis results. In the Donghai-Rizhao rock belt, tailings are dominated by the serpentine, with higher MgO content (36.81%-41.39%) and relative coarser sizes. Compared with minerals in Donghai-Rizhao tailings, a variety of hornblende are the common minerals in the Chicheng-Chaoyang tailings, with moderate MgO content (5.84%-15.60%), higher CaO content (5.68%-19.28%) and finer sizes. By field survey and calculation with the chemical equation, the carbon sequestration capacity of Chicheng-Chaoyang tailings is estimated about 4.0×108 t, which is much bigger than Donghai-Rizhao tailings. Considering chemical composition, specific surface area, the tailings resources and other factors comprehensively, mafic tailings in Chicheng-Chaoyang rock belt has the large carbon sequestration potential and can be served as one of the most promising storage sites for carbon sequestration.

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