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Study of the minerogenetic mechanism and origin of qinghai nephrite from Golmud, qinghai, Northwest China

Science China Earth Sciences 2016年第8期59卷 1597-1609页

作者： YU HaiYan WANG RuCheng GUO JiChun LI JiaGui YANG XiaoWen State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing 210023 China College of Materials Engineering Jinling Institute of Technology Nanjing 211169 China Center for Jewelry Research Nanjing University Nanjing 210093 China Jewelry Inspection Station Nanjing University Nanjing 210093 China Station of Precious Metal Gemstone Quality Control and Inspection Qinghai Province Xi'ning 810008 China

Electronic microprobe analysis showed that all QN samples are mainly composed of tremolite and minor accessory minerals, such as diopside, calcite, serpentinite, and magnetite. According to the cation coefficients, the crystallo-chemistrygenesis illustration demonstrates that all QN deposits are contact metasomatic. Depending on the mole percent of Fe^(2+(3+))/(Mg^(2+)+Fe^(2+(3+)) and the content of Cr, Co, and Ni in all QN samples measured by X-ray fluorescence spectroscopy(XRF) and inductively coupled plasma-mass spectrometry(ICP-MS), green and azure-green QNs are characterized as serpentinite-related contact metasomatic deposit(S-type), whereas white, green-white, brown, blue-violet, yellow, and viridis QNs are dolomite-related contact metasomatic deposit(D-type). The assemblages and chemical composition of accessory minerals of the eight-color QN samples show evident characteristics, which reveal four possible ore-forming processes. We also measured trace and rare earth elements(REEs) in these samples through ICP-MS to deduce the origin of and the changes in metallogenic conditions. The chondrite-normalized REE patterns of D-type QN exhibit moderately negative Eu anomalies with moderate light REE enrichment, flat heavy REE(HREE), and low(50)REE concentrations, similar to dolomitic marble. Green QN samples of S-type show enrichment in HREE and moderately negative Eu anomalies, which is consistent with characteristics of dunite. Whereas azure-green QN samples of S-type exhibit a right-dipping V-type curve with severe depletion in Eu(δEu=0.36–0.47), in accordance with the characteristics of gabbro from Yushigou ophiolite in North Qilian mountains. Furthermore, this finding is consistent with the content of trace elements and the petrographic analysis results. On the basis of several significant differences in the characteristic elements, which may have been affected by the metallogenic environment, we inferred the differences in oxygen fugacity and basicity of mine

关键词： qinghai Nephrite Tremolite Type Process Origin Environment

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A high-resolution climatic change since the Late Glacial Age inferred from multi-proxy of sediments in qinghai Lake

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Science China Earth Sciences 2005年第6期48卷 742-751页

作者： Ryo Matsumoto Geology Institute Tokyo University Tokyo 113 Japan

Based on multi-proxy analysis of pollen, carbonate, TOC, TN and δ13C of organic matters, a high-resolution climatic evolution of qinghai Lake since the Late Glacial Age is recon-structed. The results indicate that the boundary between the Last Glacial Maximum and the Late Glacial Age is at about 18.2 *** BP. The warm and wet period, which began at about 15.4 *** BP, culminated at 7.4 *** BP and came to its end at about 4.5 *** BP. After that, the climate gradually became cold and dry. The multi-proxy analysis indicates that the climate fluc-tuated greatly during the transitional period from the Late glacial Age to the Holocene, and this is in good accordance with that reflected by deep sea cores of North Atlantic, ice cores of Greenland, lake sediments in Europe, loess sequences and Guliya ice core in China. The cli-matic evolutional characteristic of the qinghai Lake since the Late Glacial Age shows that the driving force of the East-Asia Monsoon correlates with solar radiation on the ten-thousand-year scale.

关键词： qinghai Lake, Late-Glacial Age to Holocene, multi-proxy analysis, high-resolution, palaeoclimate.

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Depositional model of Permian Luodianian volcanic island and its impact on the distribution of fusulinid assemblage in southern qinghai,Northwest China

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Science China Earth Sciences 2008年第4期51卷 594-607页

作者： NIU ZhiJun XU AnWu WANG JianXiong DUAN QiFa ZHAO XiaoMing YAO HuaZhou Yichang Institute of Geology and Mineral Resources China Geological SurveyYichang 443003China

Pan-riftizational tectonic activity reached climax at Luodianian (Permian) in the East Tethyan Domain, qinghai-Tibet Plateau. Because of eruptive volcanics and influence of terrigenous materials, a complex volcanic-sedimentary landform formed on the sea floor in southern qinghai. Four sedimentary facies types were recognized based on detailed field mapping. Spatially, platform facies volcanic-limestone type was located at the center belt approximately trending NWW, surrounded by shallow water slope facies tuff/tuffite type at the two flanks and deep water slope facies breccia/calcirudite at the most outside. The depression facies sandstone-mudstone type, which comprised mainly mudstone, de-posited between volcanic islands (platform facies volcanic-limestone type). Based on the field map-ping and stratigraphic section data, seven rift-related sedimentary facies were recognized and a depo-sitional model for volcanic island was proposed. It is revealed that some volcanic island chain formed quickly and intermittently in the Qamdo Block during violent eruption, and small carbonate reef, shoal, platform occurred above or on edge of volcanic island, and some slope sedimentary facies surrounded volcano island chain during dormant period of volcanic activities. Three types of fusulinid assemblages were distinguished in the carbonate rocks, which deposited in varied positions of a palaeo-volcanic island: (1) Misellina-Schwagerina assemblage occurred above or on edge of volcanic island, (2) Para-fusulina assemblage was located at restricted depression facies among volcanic islands or carbonate platform, and (3) the reworked Pseudofusulina-Schwagerina assemblage occurred at slope facies near margin of volcanic island, which originally deposited in the shallow-water carbonate platform, then collapsed along the volcanic island margin with fusulinid-bearing grain-supported carbonate con-glomerate or calcirudite, and finally re-deposited on the deeper slope. The sedimentary sequen

关键词： volcanic rocks sedimentary facies depositional model fusulinid Permian qinghai

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A 16000-year pollen record of qinghai Lake and its paleoclimate and paleoenvironment

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Chinese Science Bulletin 2002年第22期47卷 1931-1936页

作者： LIU Xingqi SHEN Ji WANG Sumin YANG Xiangdong TONG Guobang ZHANG Enlou Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Institute of Hydrological and Environmental Geology Chinese Academy of Geological SciencesZhengding 050803China

The paleoclimate and paleoenvironment of qinghai Lake indicated by a 16000-year pollen record are as follows. It was very cold and dry before 15200 years. During the Late Glacial, the climate varied from colder and semiarid to cool and semi-humid and fluctuated frequently but with little amplitude. Three cold events in the periods of 13400-13000, 11600-12000, and 11000-10400 aBP respectively correspond to the Oldest Dryas, Older Dryas and Younger Dryas events, whereas the two warm periods between them, 12000-13000 and 11600-11000 aBP, respectively correspond to Boiling and Allerod periods. The temperature increased abruptly after the Younger Dryas event, and then the climate gradually turned to be warm and wet from warm and semiarid. In the Holocene, the largest amplitude of cold event that occurred at ca. 8200 aBP is quite prominent. The Holocene climatic optimum culminated at 6700 aBP. After 2100 aBP, the climate tended to be cold and dry, keeping on up to now. Palaeoclimatic evolution and events of

关键词： qinghai Lake pollen Lateglacial paleoclimate and paleoenvironment.

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Geophysical survey on the tectonic and sediment distribution of qinghai Lake basin

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Science China Earth Sciences 2006年第8期49卷 851-861页

作者： AN Zhisheng1, WANG Ping2, SHEN Ji3, ZHANG Yixiang2, ZHANG Peizhen4, WANG Sumin3, LI Xiaoqiang1, SUN Qianli1, SONG Yougui1, AI Li1, ZHANG Yechun2, JIANG Shaoren2, LIU Xingqi3 & WANG Yong31. Institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi’an 710075, China 2. South China Sea Institute of Oceanology, CAS, Guangzhou 510301, China 3. Nanjing Institute of Geography and Limnology, CAS, Nanjing 210008, China 4. Institute of Geology, China Earthquake Administration, Beijing 100029, China Institute of Earth Environment Chinese Academy of Sciences (CAS) Xi’an China South China Sea Institute of Oceanology CAS Guangzhou China Nanjing Institute of Geography and Limnology CAS Nanjing China Institute of Geology China Earthquake Administration Beijing China

The intensive geophysical survey of qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of qinghai Lake sediments: T1 is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.

关键词： sediment, geophysical survey, qinghai Lake.

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Environmental cost and pollution risk caused by the industrial transfer in qinghai Province

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Frontiers of Earth Science 2014年第3期8卷 362-374页

作者： Qun'ou JIANG Chengcai TANG Jinyan ZHAN Wei ZHANG Feng WU School of Soil and Water Conservation Beijing Forestry University Beijing 100038 China School of Tourism Management Beijing International Studies University Beijing 100024 China State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China

With the rising pressure due to energy consumption and costs of environmental protection and recovery, industrial transfer from the eastern to central and western areas has surged in China. However, extremely fragile ecological conditions and severe water shortage are significant hurdles for industry development in Western China. Whether the vulnerable environment can bear the pollution caused by the transferred industry from Eastern China becomes a significant issue. This study firstly estimates energy and environmental costs in different areas of China, and assesses the necessity to upgrade the industrial structure of qinghai Province. Then the emis- sions of waste water, waste gas, and smoke caused by transferred industries are calculated by Input-Output Model. On the basis of the effect analysis of waste emission on environment, pollution risks of qinghai province are assessed. The results illustrate that the costs of environmental protection and recovery in China have a gradient distribution, of which the energy efficiency is Lower while environmental costs are higher in Western China. Industrial structure adjustment has different impacts on the pollution of different sectors. Although the development of machinery and equipment, hotels and catering services, and real estate, leasing, and business services has increased the emission of pollutants, it is offset by the decreasing emissions caused by other industries such as construction and metal products. Therefore, although economic development will increase environ- mental pollution, industrial adjustments can effectively decrease waste water and waste gas emissions to reduce the pollution risk. It should be noted that there are still tremendous challenges for industrial transfer in qinghai Province to coordinate the environment and industry development.

关键词： environmental cost industrial transfer energy,pollution risk qinghai

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Modern pollen rain in the Lake qinghai basin, China

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Science China Earth Sciences 2009年第10期52卷 1510-1519页

作者： SHANG Xue LI XiaoQiang AN ZhiSheng JI Ming ZHANG HongBin State Key Lab of Loess&Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710075China Graduate University of Chinese Academy of Sciences Beijing 100049China

Lake qinghai is the largest inland brackish lake in China and lies within the NE Tibetan Plateau. Our study shows that pollen assemblages in each vegetation belt are significantly correlated with the vegetation types of this area. Among the herbaceous and shrubby pollen assemblages, Artemisia is over-represented, while Poaceae, Cyperaceae and Polygonaceae are under-represented. Artemisia/ Chenopodiaceae (A/C) ratios with the regional vegetation characteristic can be used as a proper index to reconstruct the history of vegetation and climate in Lake qinghai basin. Modern pollen in the lake mainly comes from the nearby vegetation, controlled by the directions and velocity of the wind. The distribution of modern pollen in Lake qinghai tends to be similar in most part of the lake. The difference of pollen sedimentation process in the lake can be potentially influenced by the focusing function of the lake, river streams, and lake current.

关键词： Lake qinghai basin modern pollen pollen sources dominant factors

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Origin of Aldehydes in Sediments of qinghai Lake

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Science China Chemistry 1993年第4期36卷 507-512页

作者：应光国范璞 Lanzhou Institute of Geology Academia Sinica Lanzhou 730000 PRC

This paper has analysed the aldehyde fractions in sediments and living organisms of qinghai Lake using GC-MS and discussed their origin, n-Aldehydes detected in the sediments ranged from C_(16) to C_(32) with a maximum at C_(22) C_(24) or C_(26) and showed a strong even over odd predominance. n-Aldehydes in the living organisms analysed ranged from C_(16) to C_(32) with a maximum at C_(26) or C_(28). The authors believed that aldehydes in modern sediments may directly derive from biosynthesis.

关键词： aldehyde sediment qinghai Lake.

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Late Caledonian Ductile Thrusting Deformation in the Central East Kunlun Belt, qinghai, China and Its Significance: Evidence from Geochronology

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Acta Geologica Sinica(English Edition) 2003年第3期77卷 311-319页

作者： WANG Guocan, CHEN Nengsong, ZHU Yunhai and ZHANG Kexin Faculty of Earth Sciences, China University of Geosciences, Wuhan, Hubei 430074 E-mail: wgcan@*** Ren Xifei, Liu Ruixun and Xie Guanglian China Univ Geosci Fac Earth Sci Wuhan 430074 Peoples R China

A high-angle ductile thrusting deformation with top-to-the-north movement penetratively developed in the Proterozoic-Early Paleozoic metamorphic rocks along the Central East Kunlun belt. The deformed rocks suffered epidote-amphibolite facies metamorphism. On the basis of our previous study, we present more data in this paper to further support that the ducdle thrust deformation occurred in the later Caledonian and more detailed information about the deformation. A zircon U-Pb concordant age of 446±2.2 Ma of a deformed granodiorite in the ductile thrust zone was obtained and can be interpreted as the lower limit of the deformation. A syntectonically crystallized and also strongly deformed hornblende Ar/ Ar dating gives an Ar/Ar plateau age of 426.5±3.8 Ma, which represents the deformation age. A strongly orientated muscovite gives an Ar/Ar plateau age of 408±1.6Ma, representing the cooling age after the peak temperature, constraining the upper limit of the ductile thrust deformation. This ductile thrust deformation can be interpreted as the result of the closing of the Central East Kunlun archipelago ocean. To the north, Ar/Ar plateau ages of 382.9±0.2 Ma and 386.8±0.8 Ma of muscovite in the deformed Xiaomiao Group represent the uplift cooling ages of deeper rocks after the thrusting movement. The original thrusting foliation has a low angle. A rotation model was put forward to explain the development of the foliation from the original low-angle to present high-angle dipping.

关键词： ductile thrust deformation geochronology Central East Kunlun Belt qinghai China

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Case series of COVID-19 patients from the qinghai-Tibetan Plateau Area in China

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World Journal of Clinical Cases 2021年第24期9卷 7032-7042页

作者： Ji-Jie Li Hui-Qiong Zhang Pei-Jun Li Zhi-Lan Xin Ai-Qi Xi Zhuo-Ma Yue-He Ding Zheng-Ping Yang Si-Qing Ma Department of Respiratory Medicine Qinghai Province Fourth People’s HospitalXining 810000Qinghai ProvinceChina qinghai Provincial Center for Disease Control and Prevention Xining 810000Qinghai ProvinceChina qinghai Province Fourth People's Hospital Xining 810000Qinghai ProvinceChina Department of Intensive Medicine The First People's Hospital of Qinghai ProvinceXining 810000Qinghai ProvinceChina

BACKGROUND Coronavirus disease 2019(COVID-19)is a serious infection caused by the new coronavirus severe acute respiratory syndrome coronavirus *** disease was first identified in December 2019 and has caused significant morbidity and mortality *** To explore the clinical characteristics and treatments for COVID-19 in the qinghai-Tibetan Plateau Area in *** We retrospectively analyzed the blood cell counts(neutrophils and lymphocytes),blood gas analysis,and thoracic computed tomography changes of patients from qinghai Province before,during,and after treatment(January 23,2020 to February 21,2020).In addition,we summarized and analyzed the information of critical *** data were analyzed using SPSS 17.0(SPSS Inc.,Chicago,IL,United States).The quantitative and count variables are represented as the mean±SD and n(%),*** The main symptoms and signs of patients with COVID-19 were fever,dry cough,cough with phlegm,difficulty breathing,and respiratory distress with a respiration rate≥30 times/min,finger oxygen saturation≤93%in the resting state,and oxygenation index less than 200 but greater than 100(after altitude correction).Eighteen patients with COVID-19,of whom three were critical,and the others were in a mild condition,were *** main manifestations included fever,dry cough,and *** patients developed difficulty breathing and had a *** were eventually cured and *** examinations showed one case with reduced white cell count(6%)(<4×10^(9)/L),six with reduced count of lymphocytes(33%)(<0.8×10^(9)/L),and one with abnormal blood glucose *** 18 patients were discharged,and no death *** Our findings provide critical insight into assessing the clinical diagnosis and treatment for COVID-19 in the Tibetan plateau area.

关键词： qinghai Plateau COVID-19 Blood cell Pneumonia Case series

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