Li K.,Peking University |
Zhang Z.-C.,Peking University |
Li J.-F.,Peking University |
Tang W.-H.,Peking University |
And 2 more authors.
Geological Bulletin of China | Year: 2012
The Xi Ujimqin Banner area in southern Da Hinggan Mountains is characterized by extensively-distributed Mesozoic volcanic rocks. Two groups of different age volcanic rocks in the Late Mesozoic were chosen for SHRIMP zircon U-Pb dating. The SHRIMP zircon U-Pb age of the intermediate rock is about (163 ± 2) Ma, and the dating of the Chagannuoer Formation rhyolite yields 144.2 Ma ± 1.4 Ma, indicating that these volcanic rocks were formed from Late Jurassic to Early Cretaceous, which is incompatible with the stratigraphic column. The intermediate rocks fall into trachytes belonging to the alkaline series in the TAS diagram, with enrichment of LILE and LREE and depletion of HREE and some HFSE. The rhyolites with characteristics of A2-type granite are of the high-K calc-alkaline series, with enrichment of LILE and LREE and depletion of HREE and, especially, Ba, Sr, HFSE. The trachytes originated from the fractional crystallization of the alkaline or peralkalic depleted mantle source and the rhyolites came from the middle-upper crustal magma that had suffered partial melting. Combined with the distinct geochemical features of Xi Ujimqin Banner volcanic samples and many previous researches in the study area, it is held that the Late Jurassic (163 Ma) volcanism occurred in an intense lithopheric extension tectonic setting which resulted from closure of the Mongol-Okhotsk Ocean and subsequent orogenic collapse.
Zhu X.-Y.,Beijing Institute of Geology and Mineral Resources |
Zhu X.-Y.,Sinotech Mineral Exploration Co. |
Wang J.-B.,Beijing Institute of Geology and Mineral Resources |
Wang J.-B.,Sinotech Mineral Exploration Co. |
And 5 more authors.
Geology in China | Year: 2012
The early Yanshanian granites related to tungsten and tin deposits in Nanling region have been considered to be biotite granite, monzogranite, albite granite etc. However, microscope and electron microprobe analyzes of the granite related to tungsten mineralization in Yaogangxian, Shizhuyuan, Xitian, Dengfuxian, Limu and Meiziwo show that all the feldspars of the granite consist of K-feldspar and albite (An<5), which suggests that the name should be alkali feldspar granite. The albite of greisen inclusions in the alkali feldspar shows the character An<3. There is no obvious vertical regular variation or zoning of the compositions of the albite and granite within the depth range of 1000m. On the contrary, the plagioclases of the granite inclusions (xenoliths), some granite porphyry dykes, giant batholiths, and Triassic and Paleozoic monzogranite or granodiorite have a wide range of An value of 0∼93, belonging to oligoclase, andesine or even basic plagioclase. The alkali-feldspar granite that contains two kinds of alkali feldspar was usually formed from the rich -volatile (Li -F) magma, with the extensive development of liquid immiscibility at the top of the granite, which caused the enrichment and mineralization of W, Sn, Bi, Mo in the hydrothermal-magma. The An value of the albite in alkali-feldspar granite could be used as an indicator for evaluating granite in search for W-Sn mineralization, because the value is obvious lower than that of barren granite.
Diao L.-P.,Institute of Geology and Mineral Resource Exploration |
Han R.-S.,Kunming University of Science and Technology |
Fang W.-X.,China Non ferrous Metals Resource Geological Survey
Geological Bulletin of China | Year: 2010
Determination of sampling layer, rough machining size fraction of samples and indicator elements are important contents for experimental study of soil geochemical survey of valley, directly related to the validity of the soil geochemical anomalies for using soil geochemical survey of valley to mine searching. Studied the weathering soil from limestone, basalt and shales sandstone, dried soil geochemical samples of three horizons (epipedon, illuvial horizon, parent material horizon) at room temperature. Samples sieving for Shenyang layer vibrating screen of 20, 40, 60 and 80 meshs. determined element content of samples. An experiment study on soil mechanical composition and element content of soil measured for three horizons of four size fractions (-20~+40, -40~+60, -60~+80, -80) in the Puan-Qinglong antimony-gold exploration area, determined upper part of illuvial horizon for sampling layer in the Puan-Qinglong antimony-gold exploration area, rough machining size fraction of samples is from 20 to 40 mesh fraction. The Au, Sb, As, Cu elements had been mainly considered the indicator elements. Results to ensure that, soil geochemical anomalies from soil geochemical survey of valley are effective for geological prospecting in the Puan-Qinglong antimony-gold exploration.
You J.,CAS Institute of Geology and Geophysics |
You J.,University of Chinese Academy of Sciences |
Hong T.,CAS Institute of Geology and Geophysics |
Hong T.,University of Chinese Academy of Sciences |
And 3 more authors.
Yanshi Xuebao/Acta Petrologica Sinica | Year: 2016
The time and metal logenesis of collision between different terrains is one of the hottest topics for tectonic evolution and mineralization of the Central-Asia Orogenic Belt. It's unclear that whether there is late-collisional magmatic activity in northeni Xinjiang arra The tectonic transformation time from collision to post-collision, characteristics of magmatic activity and metallogenenic response during this tectonic evolution are also undefined. The present paper reports new geochemical and chronological daia if intrusive rocks in the Xileknduke district, northern area of East Junggar. The intrusive rocks are divided ilito four types, including the 340Ma diorite . 328Ma molizonitie granIte, 325 1a granite porpliyty and 315 Ma quartz prplly. All the four kind intrusive rocks are high-K caic-alkalic. The diorites possibly formed at late-collisional setting. The diontes are rns'talununous , and have typical geochemical signatures of are, including depletion of Nb, Ta and Ti. and without depletion of P and abnormality of ôEu. The nionzonitie granites and granite porphyries possibly fornisl at the early stage of post collisional setting. The nsonzonitie granites are weakly peraliirniisoiis , and have transformational geochemical signatures of arc and post-collisional granite, such as weakly possive abnormality of ôEu , depletion of Nb, Ta and Ti, and medium depletion of 1'. The granite porphvries are weakly iwraltiminous , and have untypical geochemical signatures of post collisional grami ite , itiel imd ing negative Eu ammomnaly , the obvious depletion of NI. Ta , Ti I'. The weakly ps'raluminous quartz porphynes have typical geochemical signatures of Post collisional granite, including negative Eu anomaly, strong depletion of P. were possibly formed at post-collisional extension setting. Evidence that the intrusive rocks in the XilekLmduke district have low (hSr/wSr), ratio (0.702976 toO. 704306) and positive e(D vaiLmes ( +5.8 to +6.8) with t ages ranging from 524Ma to 588Ma suggests that they were possibly derived from partial melting of the Early Paleozoic oceanic crust. It is suggested that the Sawuer island arc had experienced live evolutional perioils in the Late I'alaeozoic as following: subditetion period (froni 400 to 370Ma) , major collision period (froni 360 to 340Ma) late-collision period (1mm 340 to 330Ma), early post-collisioni period (1mm 330 to 320Ma) and post- collisioni extension period ( from 320 to 280Ma).
Zhu X.,Beijing Institute of Geology and Mineral Resources |
Zhu X.,Sinotech Mineral Exploration Co. |
Wang J.,Beijing Institute of Geology and Mineral Resources |
Wang J.,Sinotech Mineral Exploration Co. |
And 2 more authors.
Yanshi Xuebao/Acta Petrologica Sinica | Year: 2015
Shizhuyuan large-scale skarn type tungsten and tin polymetallic ore deposit is located at Chenzhou County, Hunan Province, which occurred in the southern margin of the Qianlishan alkali feldspar granite body. The stockwork in skarn includes different types of veins, mostly alkali metamorphic vein (AMV), a few granite vein and greisen veins. The early stage AMV consists of granite vein in the central part, and K-feldspar-fluorite-wolframite in the margins, with garnet-diopside skarn alteration around the vein. The late stage AMV consists of K-feldspar, fluorite, minor actinolite, epidote, magnetite, scheelite, molybdenite, and bismuthinite. The AMV occurs only in the skarn and the skarnization marble, but is lack in the granite. The contents of CaO, TiO2, W, Bi, Mo, Cu, Pb, Zn, Sr and Ba show an increase trend from the granite, granite vein, AMV, to skarn, which may indicate an enrichment of ore materials from the magma to hydrothermal fluids. Evidence from the structure of granite vein in the center and the K-feldspar-fluorite in the margins, together with occurrence of melt or melt-fluid inclusions in the AMV indicate that the veins may have formed from a unique fluid transition from magma to hydrothermal. The evolution of this fluid is continuous from magmatic to hydrothermal process, and the mineralization started before the magma fully consolidation. We suggest the following mineralization model: Firstly, the pegmatite, massive greisen and banded wollastone-garnet skarn formed in the top and outboard of the granite in the latest magmatic stage; then in the prograde stage after widespread hydrothermal-brecciation, magma or the magma-hydrothermal transition fluid flow along the fractures of the carbonate rocks, which formed the stockwork mineralization and cause alteration of K-feldspar and garnet-diopside skarn. In the retrograde stage after magma consolidation, the mineral assemblage includes actinolite, magnetite, scheelite, molybdenum, and bismuth sulfides. In the latest sulfide stage, the temperature and fluid salinity decreased further on, and the Pb-Zn sulfides precipitate in the carbonate rocks outside the skarn. © 2015, Science Press. All rights reserved.
Yin H.,China University of Geosciences |
Zhou H.,China University of Geosciences |
Zhang W.,China University of Geosciences |
Zheng X.,China Non ferrous Metals Resource Geological Survey |
Wang S.,China University of Geosciences
Geoscience Frontiers | Year: 2016
The late Paleozoic evolution of the Wulijishanhen (WSH)-Shangdan (SD) area near to the Chaganchulu Ophiolite belt is reinterpreted. Analysis of the upper Carboniferous to lower Permian sedimentary sequence, biological associations, detrital materials, sandstone geochemistry and volcanic rocks indicates that the SD area was an epicontinental sea and rift during the late Paleozoic rather than a large-scale ocean undergoing spreading and closure. This study reveals that the actual evolution of the study area is from the late Carboniferous to the early Permian. The fusulinids Triticites sp. and Pseudoschwagerina sp. in the limestones demonstrate that the Amushan Formation develops during the late Carboniferous to the early Permian. The limestones at the base of the SD section indicate that it is a stable carbonate platform environment, the volcanic rocks in the middle of the sequence support a rift tectonic background, and the overlying conglomerates and sandstones are characteristic of an epicontinental sea or marine molasse setting. The rift volcanism made the differences in the fossil content of the SD and WSH sections and led to two sections expose different levels within the Amushan Formation and different process of tectonic evolution. Moreover, the geochemical characteristics and detrital materials of the sandstones show that the provenance and formation of the sandstones were related to the setting of active continental margin. The quartz-feldspar-lithic fragments distribution diagram indicates that the material source for the sandstones was a recycled orogenic belt. Thus, the source area of the sandstones may have been an active continental margin before the late Carboniferous–early Permian. The characteristics of the regional tectonic evolution of the area indicate that the region may form a small part of the Gobi–Tianshan rift of southern Mongolia. © 2015 China University of Geosciences (Beijing) and Peking University
Zhang W.,China University of Geosciences |
Zhu G.,China Non ferrous metals resource geological survey |
Wu Y.,Central South University
Advanced Materials Research | Year: 2013
Zimbabwe Great Dyke is a mafic-ultramafic lithosome intruded the Zimbabwe Craton. MSZ(Main Sulfide Zone) is the most important layer which contains substantial amount of PGE(Platinum Group Elements). PGE are concentrated in bottom of MSZ layer because of the intimate relationship between the content of Cu&Ni and enrichment of PGE. Acid vein rocks did not formed in the same period with the ore and adjacent rocks. Plenty of sulfide can be found in MSZ in pyroxenite, Sulfide in ore was owe to homogeneous of geochemistry process in the magmatic segregation cycle, while them in gabbro and fractures were simply by the post magmatic thermal solution activities. © (2013) Trans Tech Publications, Switzerland.
Zhang S.,Central South University |
Zhu G.,China Non ferrous Metals Resource Geological Survey |
Zhu L.,Central South University |
Zhang Y.,China Non ferrous Metals Resource Geological Survey |
Duan Z.,Central South University
Lecture Notes in Electrical Engineering | Year: 2014
GIS, together with the Internet, has had a quick development, and its application has been widely used in the recent years. The shared geospatial data has been admired by many people. So far, there have been numerous GIS platforms and data formats, which cause difficulties to the spatial data integration and sharing. There are three types of the spatial data integration at present: data format conversion mode, data interoperability mode and direct data access mode. GML is formulated by OGC, which is a coding standard based on the XML and used in the modeling, transmission, and the storage of geographic information and something associated with geographic information, and it can help sharing geospatial data. The essay takes shape data for example, introducing themethod to convert shape data format to GML format, which realizes on the C# language, and compares the result with the source data. © Springer-Verlag Berlin Heidelberg 2014.
Li D.,China Non ferrous Metals Resource Geological Survey |
Wang Y.,China Non ferrous Metals Resource Geological Survey |
Wang J.,China Non ferrous Metals Resource Geological Survey |
Wang L.,China Non ferrous Metals Resource Geological Survey |
And 2 more authors.
Acta Petrologica Sinica | Year: 2012
The mafic-ultramafic complex in the Xiangshan area of the eastern Tianshan Mts., Xinjiang, produces the medium-sized mid-Xiangshan Cu-Ni deposit and the large-scale western-Xiangshan Cu-Ni-(V)-Ti-Fe deposit. These complex rocks are composed of gabbro, ultramafic rocks and Ti-Fe gabbro. Field evidence indicates that these complex rocks intrude successively. This paper aims to prove their intruded order through combing age data of various rock series, and complementing the dating data. We suggest that the complex rocks intrude at 283.2 ± 2. 1Ma, and report some data recording tectonic-magmatic thermal event. Using the results of hornblende 40Ar/39 Ar age data, we insist that the western-Xiangshan rocks are hypogene, but the mid-Xiangshan rocks are hypabyssal, with the results of U-Pb zircon data. Thus, we believe that the erosion amount of the western-Xiangshan rocks is big, but that of the middle-Xiangshan rocks is small. Combing the field evidence, we determined the emplacement and mineralization timing orders of complex rocks in Xiangshan area.
Jinhui L.,University of Science and Technology Beijing |
Jinlong D.,China Non Ferrous Metals Resource Geological Survey
Proceedings - 2010 1st ACIS International Symposium on Cryptography, and Network Security, Data Mining and Knowledge Discovery, E-Commerce and Its Applications, and Embedded Systems, CDEE 2010 | Year: 2011
Like nuclear power station, once the irradiation room was damaged, nuclear radiation accident will occur, causing the serious nuclear panic. Therefore, a typical structure of irradiation room was presented for an example in this paper to establish a method on evaluating the resistance capability of irradiation room by explosive load. Worrying about explosives under the radical source, the greatest explosives weight was determined at the different explosion location by tensile strength of concrete, and the resistant explosive capacity of the reinforced concrete beam was accounted. © 2010 IEEE.