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Spatio-temporal patterns of drought in north xinjiang, China, 1961–2012 based on meteorological drought index

Journal of Arid Land 2015年第4期7卷 527-543页

作者： WU Yanfeng Batur BAKE ZHANG Jusong Hamid RASULOV College of Grassland and Environmental Science Xinjiang Agricultural University College of Agronomy Xinjiang Agricultural University Faculty of Hydrometeorology Tajik Agrarian University

Drought, which is one of the most frequently occurring severe hazards with long time scales and cov- ering wide geographical areas, is a natural phenomenon resulting in significant economic losses in agriculture and industry. Drought is caused by an imbalance between the inputs of and the demand for water which is insufficient to meet the demands of human activities and the eco-environment. As a major arid and semi-arid area and an important agricultural region in northwest China, north xinjiang （NX） shows great vulnerability to drought. In this paper, the characteristics of inter-annual and seasonal drought were analyzed in terms of drought occurrence and drought coverage, by using the composite index of meteorological drought and the data of daily precipitation, air temperature, wind speed, relative humidity and sunshine duration from 38 meteorological stations during the period 1961-2012. Trend analysis, wavelet analysis and empirical orthogonal function were also applied to investigate change trend, period and regional characteristics, respectively. In NX, annual and seasonal drought occurrence and drought coverage all showed a decreasing trend that was most significant in winter （with rates of-0.26 month/10a and -15.46%, respectively）, and drought occurrence in spring and summer were more frequent than that in autumn and winter. Spatially, drought was severe in eastern regions but mild in western regions of NX. Annual and seasonal drought occurrence at 38 meteorological stations displayed decreasing trends and were most significant in ＂Shi- hezi-Urumqi-Changji＂, which can help to alleviate severe drought hazards for local agricultural production and improve human livelihood. NX can be approximately classified into three sub-regions （severe drought region, moder- ate drought region and mild drought region）, which were calculated from annual drought frequencies. The cross wavelet transform suggested that SOl （Southern Oscillation Index）, AOI （Arctic Oscillation I

关键词： drought spatio-temporal pattern drought indices north xinjiang

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Metallogenic Series Related to Permian Mafic Complex in north xinjiang:Post-collisional Stage or Mantle Plume Result?

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Acta Geologica Sinica(English Edition) 2008年第4期82卷 788-795页

作者： WANG Yuwang WANG Jingbin WANG Lijuan LONG Lingli School of the Earth Sciences and Resources China University ofGeosciences Beijing 100083 China Beijing Institute of Geology for Mineral Resources Beijing 100012 China

There are four deposit types related to a Permian mafic complex in northern xinjiang, i.e., copper-nickel sulfide deposit, vanadic titanomagnetite deposit, magnetite （-cobalt） deposit and Cu-Ni- VTiFe composite deposit. The deposits are distributed spanning tectonic units with close and consecutive metallogenic ages. A transitional deposit type can occur among the end-member deposits. Trace elements of host rocks show that they can derive from similar source area. Hence, they constitute a particular metallogenic series related to a mafic-ultramafic complex that is also a symbol series of the post-collisional stage of the Central Asia Metallogenic Province （CAMP）. The metallogenic ages of the series are between 260 Ma and 300 Ma throughout the Permian. Unlike mineralization from a mantle plume, the metallogenic period of this series spans at least 40 Ma. Compared with related deposits of the Emeishan mantle plume, the north xinjiang series has a similar ore-forming element assemblage but has preferably developed Cu-Ni sulfide deposits rather than vanadic titanomagnetite deposits. In concomitance with this series, north xinjiang area has developed a set of syntectonic Au-Cu-Mo metallogenic series related to a felsic volcanic-intrusive complex, which might indicate that there is no direct relationship with mantle plume activity. From early to late, i.e., the sequence of copper-nickel sulfide to magnetite （-cobalt） to vanadic titanomagnetite deposit, the host rock series evolves from mafic-ultramafic and tholeiite series to mafic and alkalic series, the ~REE content tends to increase with increasing of REE fractionation, and some of the trace elements （particularly LIL） also show an increasing tendency. The above evolutionary regularity possibly reflects a course where the magma source deepens and thermal interface moves down, energy gradually exhausts, and neo-continental crust forming in the postcollision stage tends to stabilize.

关键词： metallogenic series mafic complex mantle-derived magma post-collision Permian north xinjiang China

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A Report of the Newly Discovered Cu–Ni Ore Deposit in the West of East Tianshan, north xinjiang, China

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 857-858页

作者： CHEN Baoyun YU Jinjie WANG Junliang TIAN Jiangtao LI Dahai LIU shuaijie WANG Cheng MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources CAGS Beijing 100037 China xinjiang Geological Survey Urumqi 830000 China

Objective The Early Permian mafic-ultramafic intrusions （298- 270 Ma, Mao et al., 2008）, which are widely distributed in different tectonic domains in north xinjiang, host magmatic sulfide ore deposits, making north xinjiang the second most important region for Ni resources in China. The bulk of Cu-Ni ore deposits in East Tianshan, making up a large portion of Ni resources in north xinjiang, were concentrated in the east of East Tianshan （the Huangshan- Jing＇erquan region）（Feng Yanqing, et al., 2017）, while no any analogue was discovered in the west of East Tianshan until the Lubei Cu-Ni （Co） ore deposit （90°21＇E, 42°10rN） was identified by xinjiang Geological Survey in 2014. The Lubei Cu-Ni （Co） ore deposit is a medium- to large- sized deposit with Ni and Cu grades in the range 0.2%- 7.76% and 0.2%-2.30%, respectively. This work has initiated the prospection for a large-sized Cu-Ni ore deposit in the west of East Tianshan.

关键词： north xinjiang A Report of the Newly Discovered Cu China Ni Ore Deposit in the West of East Tianshan

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Problems of PGE metallogenesis related to mafic-ultramafic complexes in north xinjiang,China

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Geoscience Frontiers 2011年第2期2卷 187-198页

作者： Yuwang Wang Jingbin Wang Lijuan Wang Lingli Long Zhen Liao Huiqiong Zhang Pingzhi Tang Beijing Institute of Geology for Mineral Resources Beijing 100012 China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Platinum group element （PGE） mineralization is mostly related to mafc--ultramafic complexes of the dominant magmatic deposit type. Mineralization of this type mainly relies on two conditions： the abundance of PGE in magma, and the presence of mechanisms favorable to PGE enrich- ment and separation from sulfur-saturated magma during magmatic evolution. Mafic-ultramafic complexes are widely developed in north xinjiang, including （1） the large-scale copper-nickel deposits of Kelatongke, Huangshan, Huangshan East, and Tulargen, （2） numerous small to medium-sized copper- nickel deposits such as Xiangshan, Tudun, Hulu, Baishiquan, and （3） the Xiangshan West and Weiya medium-sized V--Ti magnetite deposits. However, mafic-ultramafic complexes in north xinjiang rarely form PGE deposits. Therefore, questions about PGE metallogenesis in north xinjiang are discussed in this paper from the standpoint of the ore-forming mechanism of PGE deposits and the characteristics of the north xinjiang magma sources. The rock types of the post-collisional mafic--ultramafic complexes in north xinjiang are of a ferrous rock series formed by fractional crystallization, a rock type generally favorable for hosting PGE. For the Cu-Ni sulfde deposits of north Xingjiang, the assimilation of crustal material causes sulfide liquation during processes of magmatic evolution and mineralization. This can be shown petrogeochemically, including the characteristics of Sr, Nd, Pb, O, Os, and S isotopes, which indi- cate a magmatic ore-forming mechanism for the Xingjiang PGE deposits. The principal reason for weak PGE mineralization in north xinjiang may be ascribed to a widely-developed depleted mantle source （with positive end values） that underlies it. The north xinjiang lithosphere is not of typical Precambrian cratonal type, but has more affinities with modified oceanic lithosphere or immature continental lithosphere that would constitute PGE-poor original magma sources unfavorable to PGE mineralization.

关键词： Mafic-ultramaficcomplex PGE mineralization Nd isotope Ore-forming mechanisms north xinjiang

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Comparison of Calculation Methods for Potential Reference Crop Evapotranspiration ET_0 in north xinjiang

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Agricultural Science & Technology 2017年第5期18卷 920-923页

作者： Chunyan YIN Hu LIU Ruiqiang ZHANG Jian WANG Yongfu WEI Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Institute of Water Resources for Pastoral Area Ministry of Water Resources

Reference crop evapotranspiration (ET_0) is a critical part in water cycle and water balance of ecosystem, which is greatly important to effective utilization of agricultural water resources and for making reasonable irrigation system. In order to propose a suitable method for computing ET_0 in north xinjiang, based on daily meteorological data from May 1 to September30, 2010 provided by Weather Station of Fuhai County, we used FAO56 Penman-Monteith as the standard formula to compute ET_0, compared the differences and relations between such the method and other 4 calculation formulas, and analyzed the cause of the deviation, finally evaluated the applicability of computational method in north xinjiang. The results showed that the calculation results by FA056 PM Method was approximate to that by FAO Penman method and IA method, of which the relative error was 9.26% and 13.51% respectively, the ET_0 results calculated by PT method and HS method were generally greater than the results by FAO56 PM, and their deviation was very obvious.

关键词： north xinjiang Reference crop evapotranspiration Calculation method FAO56 PM

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Paleozoic Epithermal Au and Porphyry Cu Deposits in north xinjiang,China:Epochs,Features,Tectonic Linkage and Exploration Signi ficance

Paleozoic Epithermal Au and Porphyry Cu Deposits in North Xi...

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中国科学院地质与地球物理研究所2003学术年会

作者： Kezhang QIN,Shu SUN,Jiliang LI,Tonghui FANG~*,Shulai WANG~* and Wei LIU Key Laboratory of Mineral Resources.Institute of Geology and Geophysics,Chinese Academy of Sciences.Beijing 100029,China * Beijing Institute of Geology for Mineral Resources,Beijing 100012,China

Based on field investigation of large number of ore deposits including some latest discoveries and multidiscipline comprehensive research,we demonstrated the general features of metallic deposits and we suggest that Paleozoic archipelago -type collisional orogen at north xinjiang,northwestern China show intimate similarity with the metallogenesis of Southeast Asia Cenozoic *** briefly described the characteristics of major porphyry-type,skarn-type Cu deposits and typical high-sulfidation type(HS-type) and low-sulfidation type(LS-type) epithermal Au deposits as well as some latest *** isotopic age-dating on the Tuwu-Yandong superlarge porphyry Cu deposits revealed that they formed in Late Devonian to Early Carboniferous in an accretionary arc *** tectonic settings of epithermal Au deposits and its linkage with porphyry Cu deposits are further *** formation condition for porphyry Cu deposits is more strict than epithermal Au *** distribution width for porphyry Cu deposits in the orogenle belts is more limited than epithermal Au *** discovery and prospecting progress of the Kalatage HS-typc Cu-Au deposit were *** significance in further exploration was suggested.

关键词： Paleozoic porphyry Cu epithermal Au epochs accretionary arc north xinjiang NW China

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Paleozoic Epithermal Au and Porphyry Cu Deposits in north xinjiang,China:Epochs,Features,Tectonic Linkage and Exploration Significance

Paleozoic Epithermal Au and Porphyry Cu Deposits in North Xi...

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中国科学院地质与地球物理研究所2002学术年会

作者： Kezhang QIN~a,Shu SUN~a,Jiliang LI~a,Tonghui FANG~b,Shulai WANG~b and Wei LIU~a a.Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China b.Beijing Institute of Geology for Mineral Resources,Beijing 100012,China

Based on field investigation of large number of ore deposits including some latest discoveries and multidispline comprehensive research,we demonstrated the general features of metallic deposits and we suggest that Paleozoic archipelago-type collisional orogen at north xinjiang,northwestern China show intimate similarity with the metal logenesis of Southeast Asia Cenozoic *** briefly described the characteristics of major porphyry-type,skarn-type Cu deposits and typical high-sulfidation type(HS-type) and low-sulfidation type(LS-type) epithermal Au deposits as well as some latest *** isotopic age-dating on Tuwu-Yandong superlarge porphyry Cu deposits revealed that they formed in Late Devonian to Early Carboniferous in a accretionary arc *** tectonic settings of epithermal Au deposits and its linkage with porphyry Cu deposits are further *** formation condition for porphyry Cu deposits is more stricter than epithermal Au *** distribution width for porphyry Cu deposits in the orogenic belts is more limited than epithermal Au *** discovery and prospecting progress of Kelatage HS-type Cu-Au deposit was *** significance in further exploration was suggested.

关键词： Paleozoic porphyry Cu epithermal Au epochs accretionary arc north xinjiang NW China

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Vegetation and environment changes inferred from pollen records since 3000 cal. yr BP in Kanas wetland, xinjiang

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Journal of Plant Ecology 2019年第5期12卷 907-916页

作者： Yumei Li Yun Zhang Zhaochen Kong Long Zhao Li Wang Yuanyuan Li Lixin Chen State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China College of Earth Sciences Jilin UniversityChangchun 130061China Beijing Geological and Mineral Exploration and Development Bureau Beijing 100195China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

Aims climate change can significantly affect the vegetation ***,paleovegetation and paleoclimate reconstruction should consider the quantitative relationship between modern vegetation and *** specific objectives of this study were(i)to assess the influence of environmental variables on pollen assemblages in the Kanas region,(ii)to reconstruct the evolution of vegetation over the past 3000 years using pollen records and(iii)to quantify historical climate change(including mean annual temperature and total annual precipitation)using a weighted averaging partial least squares regression method(WAPLS)applied to fossil pollen data from the Kanas wetland in xinjiang,*** A total of 65 surface and 50 fossil samples were collected from the Kanas wetland and analysed for 14c,pollen and grain *** com-bining these data with those obtained from 214 samples of surface pollen assemblages in north xinjiang,the late Holocene climate was reconstructed using a WAPLS *** Findingsthe vegetation in Kanas was dominated by forest for the past 3000 years,undergoing an arbour-vegetation transition from predominantly pine to spruce over that *** WAPLS model showed that the paleoclimate progressed from cold-wet to warm-dry and subsequently back to *** to 1350 calibrated years before the present(*** BP),the climate of Kanas was cold and wet,and conditions became increasingly warm and dry until 870 *** *** temperature reconstruction model indicated that a‘Little Ice Age’occurred~380 *** *** data will help us improve the understanding of abrupt climate change and provide important information regarding the prediction of climate.

关键词： climate change Kanas wetland north xinjiang pollen grain size

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