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Middle Permian Seamount from Xiahe Area, Gansu Province, Northwest China: Zircon U-Pb Age, Biostratigraphy and Tectonic Implications

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Journal of China University of Geosciences 2009年第2期20卷 364-380页

作者：寇晓虎张克信朱云海陈中强林启祥陈奋宁黄金元 Key Laboratory of Biogeology and Environmental Geology of Ministry of Education Faulty of Earth SciencesChina University of Geosciences State Key Laboratory of Geological Processes and Mineral resources Key Laboratory of Biogeology and Environmental Geology of Ministry of EducationChina University of Geosciences faulty of earth Sciences China University of Geosciences School of earth & Environment The University of Western Australia

The well-preserved seamount buildups are documented from the northwestern Qinling （秦岭） orogenic belts, Northwest China. The study sections are located in the Ganjia （甘加） area of the Xiahe （夏河） County, Gansu （甘肃） Province. The dark basalt and overlying massive reef carbonate characterize the Xiahe seamount buildup. Basalts are dominated by the olivine type of rocks and bear distinct porphyritic textures, and fumarole and amygdaloidal structures. The basalts are dominated by SiO2 （up to 48.49 wt.%-52.29 wt.%） followed by （Na2O＋ K2O）（3.80 wt.%-4.96 wt.%） and TiO2 （2.04 wt.%-2.52 wt.%）. They are featured by considerably high content of Ti. The tholeiiteseries rocks dominate the basalts, while calc-alkali-series rocks are also present. The REE of the basalts shows the LREE-enrichment type with distinct positive Eu abnormal. The trace elements of the basalts are characterized by the lack of P and high content of Ti. These geochemical signals suggest that the Xiahe basalts were formed in an ocean-island setting. The LA ICP-MS zircon U-Pb age of the basalts is 267.6±5 Ma, which is reinforced by the presnce of the fusulinid Neoschwagerina Zone of the Wordian （Middle Permian） in the limestone interbeds of the basalts. Integration of petrological and geochemical studies of seamount basalts and lateral correlation of seamount buildups reveals that the Qinling-Qilian-Kunlun orogenic belts were probably the archipelagic oceans during the Permian.

关键词： seamount basalt zircon U-Pb age biostratigraphy geochemistry petrology Middle Permian western Qinling tectonic complex Northwest China.

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Petrological and Geochemical Constraints on the Protoliths of Serpentine-Magnetite Ores in the Zhaoanzhuang Iron Deposit,Southern North China Craton

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 627-665页

作者： MENG Jie LI Houmin LI Lixing SANTOSH M SONG Zhe YANG Xiuqing MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China State Key Laboratory of Geological Processes and Mineral resources School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China Department of earth Sciences University of Adelaide SA 5005 Australia faulty of earth resources China University of Geosciences Wuhan 430074 China Chang'an University Xi'an 710064 China

The uncommon Mg-rich and Ti-poor Zhaoanzhuang serpentine-magnetite ores within Taihua Group of the North China Craton （NCC） remain unclear whether the protolith was sourced from ultramafic rocks or chemical sedimentary sequences. Here we present integrated petrographic and geochemical studies to characterize the protoliths and to gain insights on the ore-forming processes. Iron ores mainly contain low-Ti magnetite （TiO2 -0.1wt%） and serpentine （Mg#=92.42-96.55）, as well as residual olivine （Fo=89-90）, orthopyroxene （En=89-90） and hornblende. Magnetite in the iron ores shows lower AI, Sc, Ti, Cr, Zn relative to that from ultramafic Fe-Ti-V iron ores, but similar to that from metamorphic chemical sedimentary iron deposit. In addition, interstitial minerals of dolomite, calcite, apatite and anhydrite are intergrown with magnetite and serpentine, revealing they were metamorphic, but not magmatic or late hydrothermal minerals. Wall rocks principally contain magnesian silicates of olivine （Fo=83-87）, orthopyroxene （En=82-86）, humite （Mg#=82-84） and hornblende [XMg=0.87--0.96]. Dolomite, apatite and anhydrite together with minor magnetite, thorianite （Th-rich oxide） and monazite （LREE-rich phosphate） are often seen as relicts or inclusions within magnesian silicates in the wall rocks, revealing that they were primary or earlier metamorphic minerals than magnesian silicates. And olivine exists as subhedral interstitial texture between hornblende, which shows later formation of olivine than hornblende and does not conform with sequence of magmatic crystallization. All these mineralogical features thus bias towards their metamorphic, rather than magmatic origin. The dominant chemical components of the iron ores are SiO2 （4.77-25.23wt%）, Fe203T （32.9-80.39wt%） and MgO （5.72- 27.17wt%） and uniformly, those of the wall rocks are also SiO2 （16.34-48.72wt%）, MgO （16.71- 33.97wt%） and Fe203T （6.98-30.92wt%）. The striking high Fe-Mg-Si contents reveal that protolith of the Zhaoanzhu

关键词： protolith serpentine-magnetite ores Fe-Mg-Si-rich rocks Zhaoanzhuang North China Craton

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Sedimentary Evolution of the Qinghai-Tibet Plateau in Cenozoic and its Response to the Uplift of the Plateau

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Acta Geologica Sinica(English Edition) 2013年第2期87卷 555-575页

作者： ZHANG Kexin WANG Guocan XU Yadong LUO Mansheng JI Junliang XIAO Guoqiao WANG An SONG Bowen LIANG Yinpin JIANG Shangsong CAO Kai CHEN Fenning CHEN Ruiming YANG Yongfeng Key Laboratory of Biological and Environmental Geology of Ministry of Education China University of Geosciences faulty of earth Sciences China University of Geosciences State Key Laboratory of Geological Processes and Mineral resources China University of Geosciences Xi'an Institute of Geology and Minerals resources Region of Shaanxi Bureau of Geology and Mineral resources and Mineral Research

We have studied the evolution of the tectonic lithofacies paleogeography of Paleocene- Eocene, Oligocene, Miocene, and Pliocene of the Qinghai-Tibet Plateau by compiling data regarding the type, tectonic setting, and iithostratigraphic sequence of 98 remnant basins in the plateau area. Our results can be summarized as follows. （1） The Paleocene to Eocene is characterized by uplift and erosion in the Songpan-Garze and Gangdise belts, depression （lakes and pluvial plains） in eastern Tarim, Qaidam, Qiangtang, and Hoh Xil, and the Neo-Tethys Sea in the western and southern Qinghai-Tibet Plateau. （2） The Oligocene is characterized by uplift in the Gangdise--Himalaya and Karakorum regions （marked by the absence of sedimentation）, fluvial transport （originating eastward and flowing westward） in the Brahmaputra region （marked by the deposition of Dazhuka conglomerate）, uplift and erosion in western Kunlun and Songpan-Garze, and depression （lakes） in the Tarim, Qaidam, Qiangtang, and Hoh Xil. The Oligocene is further characterized by depressional littoral and neritic basins in southwestern Tarim, with marine facies deposition ceasing at the end of the Oligocene. （3） For the Miocene, a widespread regional unconformity （ca. 23 Ma） in and adjacent to the plateau indicates comprehensive uplift of the plateau. This period is characterized by depressions （lakes） in the Tarim, Qaidam, Xining-Nanzhou, Qiangtang, and Hoh Xil. Lacustrine facies deposition expanded to peak in and adjacent to the plateau ca. 18-13 Ma, and north-south fault basins formed in southern Tibet ca. 13-10 Ma. All of these features indicate that the plateau uplifted to its peak and began to collapse. （4） Uplift and erosion occurred during the Pliocene in most parts of the plateau, except in the Hoh Xil-Qiangtang, Tarim, and Qaidam. The continuous uplift and intensive taphrogeny in the plateau divided the original large basin into small basins, deposition of lacustrine facies decreased considerably, and boulderst

关键词： lithofacies paleogeography depositional evolution uplift event Cenozoic Qinghai-Tibet Plateau

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Late Pleistocene sedimentary sequences and paleoclimate changes in Xunhua basin in the upper reach of Yellow River in China

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Frontiers of earth Science 2012年第3期6卷 297-305页

作者： Fang HAN Kexin ZHANG Junliang JI Yadong XU Fenning CHEN Xiaohu KOU faulty of earth Sciences China University of GeosciencesWuhan 430074China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China Xi'an Institute of Geology and Mineral resources Xi'an 710054China

The third terrace of the Yellow River was well developed in Xunhua basin in the north-east margin of the Tibetan Plateau. The terrace was formed at ca 75 ka as dated by the optically stimulated luminescence （OSL） method. On the basis of grain size, magnetic susceptibility and palynological data, six episodes of the climatic change were identified in Xunhua basin; they include very warm and humid period during 120-114 ka, cool and dry period during 114-105 ka, warm and humid period during 105- 98 ka, gradually cooling period during 98-85 ka, warm and humid period during 85-75 ka, very cold and dry period during 75-63 ka. The six stages of climatic change recorded in Xunhua basin correspond to the marine oxygen isotope stages （MIS） of 5e, 5d, 5c, 5b, 5a and 4, respectively.

关键词： sedimentary sequences river terrace Xunhuabasin Tibetan Plateau Late Pleistocene paleoclimaticchange

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Spatio-temporal framework of tectonic uplift stages of the Tibetan Plateau in Cenozoic

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Science China earth Sciences 2011年第1期54卷 29-44页

作者： WANG GuoCan CAO Kai ZHANG KeXin WANG An LIU Chao MENG YanNing XU YaDong State Key Laboratory of Geological Processes and Mineral resources China University of Geosciences Wuhan 430074 China faulty of earth Sciences China University ofGeosciences Wuhan 430074 China The Bureau of Non-ferrous Geology of Liaoning Province Shenyang 110013 China

Four intensive uplift periods, i.e., 60–35, 25–17 and 12–8 Ma (but 18–13 Ma in the Himalayas of the southern Tibet), and since about 5 Ma, can be determined on the Tibetan Plateau by synthetical analysis of low-temperature thermo-chronology data, sedimentary deposit records, and structural deformation records of different areas. The strong tectonic uplift periods in different areas on the Tibetan Plateau are penecontemporaneous, except for the Himalayan area of the southern Tibet, where a rapid uplift and exhumation period, controlled by the activity of the South Tibetan Detachment System faults, occurred during 18–13 Ma. These strong uplift and exhumation periods correspond well to intensive deformation activity periods, suggesting tectonically-controlled uplift and exhumation. The deposit records, such as the distribution of coarse clastic sediments, the distribution of tectonically-controlled basins, stratigraphic discontinuousness or unconformity, and fault-controlled geomorphologic evolution, also match well with the strong uplift and exhumation periods. Expanding processes of the plateau are also discussed.

关键词： Tibetan Plateau Cenozoic intensive tectonic uplift and exhumation periods plateau growth and expansion

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Lateral Stress Concentration in Localized Interlayer Rock Stratum and the Impact on Deep Multi-Seam Coal Mining

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International Journal of Geosciences 2013年第9期4卷 1248-1255页

作者： Mingwei Zhang Hideki Shimada Takashi Sasaoka Kikuo Matsui Department of earth resources Engineering Faulty of Engineering Kyushu University Fukuoka Japan

To explore the impact of lateral stress concentration in interlayer rock stratum on the exploitation of protected coal seam, a field experiment was carried out in a multi-seam mining structure. Lateral stress redistribution and interlayer rock failure behavior were surveyed. Then an assistant numerical investigation was implemented to evolve the effect of liberated seam mining and its influence on stress reconstruction in surrounding rock mass. The cause of lateral stress concentration and its impact were discussed finally. Key findings turn out that a certain lateral stress increases in interlayer rock stratum and concentrates on its lower region. Lateral stress concentration and interlayer rock failure are interactional. The former is an inducing factor of the latter;the latter promotes the increase of concentration degree. Extent of lateral stress concentration increases to the maximum as seam distance is about 50 m. But the efficacy of liberated seam mining decreases as the seam spacing gets larger. Protected seam mining is then classified based upon the impact of lateral stress concentration, which helps to prevent the rock burst hazard and then to achieve a reliable mining in deep mines.

关键词： Lateral Stress Concentration Interlayer Rock Stratum Multi-Seam Coal Mining Stress Relaxation Zone Floor Failure Behavior

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Cenozoic sedimentary records and geochronological constraints of differential uplift of the Qinghai-Tibet Plateau

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Science China earth Sciences 2008年第11期51卷 1658-1672页

作者： ZHANG KeXin WANG GuoCan CAO Kai LIU Chao XIANG ShuYuan HONG HanLie KOU XiaoHu XU YaDong CHEN FenNing MENG YanNing CHEN RuiMing Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral resources China University of GeosciencesWuhan 430074China faulty of earth Sciences China University of GeosciencesWuhan 430074China

Geological mapping data (1:250000) in the Qinghai-Tibet Plateau and its adjacent regions reveal the sediment sequences, distribution and tectonic evolution of the 92 Tertiary remnant basins. Southern Tibet and the Yecheng area in Xinjiang, located at southern and northwestern margins of the Qinghai-Tibet Plateau, respectively, were parts of the Neo-Tethys remnant sea in the Paleogene. In southern Tibet, both the subabyssal and abyssal sequences occur at the Gyangze, Saga, Guoyala, and Sangmai areas. The deep-water facies successions outcrop in the west, whereas the shallow-water facies sequences in the east, indicating the east to the west retreat of the Neo-Tethys Ocean. The retreat of the Neo-Tethys Ocean in the east was contributed to the earlier tectonic uplift of the eastern Qinghai-Tibet Plateau. The uplift process of the Plateau from the Late Cretaceous to Pliocene is described as follows: During the Late Cretaceous, tectonic uplift of the Qinghai-Tibet Plateau occurred in the northeastern part and the configuration of the Qinghai-Tibet Plateau was characterized by rise in the northeast and depression in the west. In the Paleocene-Eocene interval, the Tengchong-Baingoin and Kuyake-Golmud areas experienced local tectonic uplifting, the West Kunlun uplift zone broadened easterly, the Qilian uplift zone broadened southerly, and the Songpan-Garzê uplift zone shrank easterly. The Oligocene configuration of the Qinghai-Tibet Plateau was characterized by mountain chains rising along its margins and sedimentary basins in the central part because of tectonic uplifts of the Gangdisê and the Himalaya blocks. Meanwhile, the Kunlun-Altyn-Qilian uplift zones have also broadened southerly and northerly. In contrast, the great uplift zones of the Gangdisê, the Himalaya, the Karakorum, and the Kunlun blocks characterize the paleogeographic contours of the Qinghai-Tibet Plateau during the Miocene-Pliocene. Additionally, the thermochronological data on tectonic uplift events in

关键词： Cenozoic tectonic uplift thermochronology sedimentary records the Qinghai-Tibet Plateau

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Paleogene-Neogene stratigraphic realm and sedimentary sequence of the Qinghai-Tibet Plateau and their response to uplift of the plateau

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Science China earth Sciences 2010年第9期53卷 1271-1294页

作者： ZHANG KeXin WANG GuoCan JI JunLiang LUO ManSheng KOU XiaoHu WANG YueMing XU YaDong CHEN FenNing CHEN RuiMing SONG BoWen ZHANG JianYu LIANG YinPing Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of GeosciencesWuhan 430074China faulty of earth Sciences China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral resources China University of GeosciencesWuhan 430074China Geological Survey of China University of Geosciences Wuhan 430074China Gansu Province Bureau of Geo-exploration and Mineral Development Lanzhou 730000China Xi’an Institute of Geology and Mineral Xi’an 710054China

Based on the data of 1:250000 geological mapping completed by CGS and the previous literature of the Cenozoic strata, 98 remnant basins and 5 stratigraphic realms with 13 stratigraphic subrealms have been recognized on the Qinghai-Tibet Plateau and its adjacent area. Through the research of the types of remnant basins, tectonic setting, stratigraphic sequence and sedimentary characteristics, contact relationship between the strata, the formation time and evolution history of sediments, we divided the uplift process and sedimentary response of the Qinghai-Tibet Plateau into 3 stages and 8 sub-stages, namely, subduction-collision uplift stage (65-34 Ma) with three sub-stages, intercontinental convergence and compressive uplift stage (34-13 Ma) with three sub-stages, and intercontinental isostatic adjustment uplift stage (since 13 Ma) with two sub-stages.

关键词： Paleogene-Neogene remnant basin stratigraphic realm sedimentary evolution Qinghai-Tibet Plateau

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Corrosion and Electrochemical Behavior of Zn-Cu-Ti Alloy Added with La in 3% NaOH Solution

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Journal of Wuhan University of Technology(Materials Science) 2016年第2期31卷 408-416页

作者：冀盛亚 LIANG Shuhua 宋克兴 WANG Qing faulty of Materials Science and Engineering Xi'an University of Technology Xi'an 710048 China School of Materials Science and Engineering Henan University of Science and Technology Luoyang 471023 China Department of Materials Engineering Henan Institute of Technology Xinxiang 453003 China

The corrosion mechanism of Zn-Cu-Tialloy added with La in 3% NaOH solution was investigated by electrochemicaltesting and SEM *** curves manifested that the overallcorrosion kinetics of alloys are under anodic *** anodic passivation of the Zn-Cu-Tialloy is remarkably improved by the addition of *** La can effectively improve the hydrogen evolution/oxygen reduction over-potentialof alloy elements,and the rare earth oxide film plays an important role in insulation that can strengthen the dielectric properties of Zn-Cu-Tialloy,the corrosion resistance of Zn-Cu-Tialloy is made significantly better by adding a trace amount of *** improvement of corrosion resistance is not positively correlated with the adding amount of La to *** Zn-Cu-Ti-0.5La alloy displays the best corrosion resistance *** corrosion form of the alloys mainly belongs to a selective corrosion and the main solid corrosion products are Zn（OH）_2 and ZnO.

关键词： Zn-Cu-Ti alloy rare earth La polarization curves EIS selective corrosion

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Assessment of Soil Erosion and Sediment Yield in Liao Watershed, Jiangxi Province, China, Using USLE, GIS, and RS

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Journal of earth Science 2010年第6期21卷 941-953页

作者：李辉陈晓玲 Kyoung Jae Lim 蔡晓斌 Myung Sagong faulty of earth Sciences China University of Geosciences Three Gorges Research Center for Geo-hazard Ministry of Education China University of Geosciences The Key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University State Key Laboratory for Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Department of Agricultural Engineering Kangwon National University Institute of Geodesy and Geophysics Chinese Academy of Sciences Track & Civil Engineering Research Department Korea Railroad Research Institute

Soil erosion by water is a serious problem all over the world. In China, about 1 790 000 km2 of land suffers from water erosion, which accounts for 18.3% of China＇s total area. This study was conducted in the Liao （潦） watershed in Jiangxi （江西） Province to assess annual soil erosion and sediment yield using the Universal Soil Loss Equation （USLE）. A geographic information system （GIS） was used to generate maps of the USLE factors, which include rainfall erosivity （R）, soil erodibility （K）,slope length and steepness （LS）, cover （C）, and conservation practice （P） factors. By integrating these factors in a GIS, a spatial distribution of soil erosion over the Liao watershed was obtained. The soil erosion was found to vary from nil for flat and well-covered areas to more than 500 t/ha/a in mountainous places with sparse vegetation. The average soil erosion is 18.2 t/ha/a with a standard deviation of 109.3 t/ha/a. The spatial distribution of erosion classes was estimated. About 39.5% of the watershed is under the tolerant erosion rate, and 60.5% of the study area experienced erosion to different extents. A spatially distributed sediment delivery ratio （SDR） module was developed to account for soil erosion and deposition. It was found that the SDR value at the outlet of the Liao watershed was 0.206, and the sediment yield was 1.32 million t/a, which was 20% higher than the measured sediment. The results can be used to identify the soil erosion hot spots and develop the best soil erosion management practices and help estimate the quantity of soil that was transported into the downstream Poyang （鄱阳） Lake.

关键词： soil erosion USLE GIS sediment delivery ratio.

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