Tianjin North China Geological Exploration Bureau

Tianjin, China

Tianjin North China Geological Exploration Bureau

Tianjin, China
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Wang Y.,Central South University | Yu S.,Tianjin North China Geological Exploration Bureau | Wang J.,Southwest University of Science and Technology | Lu D.,Central South University
Mineral Processing and Extractive Metallurgy Review | Year: 2017

The surface physicochemical properties of cervantite are similar to the gangue minerals, so it is difficult to achieve the flotation separation of cervantite from them. In order to improve the floatability of cervantite, the phase and floatability changes of cervantite were investigated by the sulphidization roasting with element sulfur in reducing atmosphere and flotation tests. Cervantite did not float while using isoamyl xanthate as collector. But its floatability improved greatly by the sulphidization roasting with element sulfur, and a sulfide layer of Sb2S3 is found to be the key component which causes the hydrophobic of sulphidized cervantite. The flotation recovery of sulphidized cervantite increased from 5% to 95% while the molar ratio of S:Sb changed from 0 to 1.5. In other words, the floatability of the sulphidized cervantite increased with the increase of sulfide layer thickness. However, the sulfide layer thickness depended on the additive amount of element sulfur, roasting time and temperature. In the process of sulphidization roasting,element sulfur changed first from solid state to liquid state, then the liquid sulfur reacted with the surface of cervantite, and the stibium phase experienced the following change of Sb2O4→Sb2O3(O)/Sb2O3(C)→Sb2S3. In addition, the Sb2S3 phase will further react with Sb2O4 if there is lack of element sulfur in the sulphidization roasting system. © 2017 Taylor & Francis

Cheng X.-H.,University of Science and Technology Beijing | Xu J.-H.,University of Science and Technology Beijing | Xue Q.-P.,Tianjin North China Geological Exploration Bureau | Zhang H.,University of Science and Technology Beijing
Canadian Journal of Earth Sciences | Year: 2017

The Hamadi gold deposit is located in North Sudan, and occurs in the Neoproterozoic metamorphic strata of the Arabian–Nubian Shield. Two types of gold mineralization can be discerned: gold-bearing quartz veins and altered rock ores near ductile shear zones. The gold-bearing quartz veins are composed of white to gray quartz associated with small amounts of pyrite and other polymetallic sulfide minerals. Wall-rock alterations include mainly beresitization, epidotization, chloritization, and carbonatization. CO2-rich inclusions are commonly seen in gold-bearing quartz veins and quartz veinlets from gold-bearing altered rocks; these include mainly one-phase carbonic (CO2 ± CH4 ± N2) inclusions and CO2–H2O inclusions with CO2/H2O volumetric ratios of 30% to ~ 80%. Laser Raman analysis does not show the H2O peak in carbonic inclusions. In quartz veins, the melting temperature of solid CO2 (Tm,CO2) of carbonic inclusions has a narrow range of −59.6 to −56.8 °C. Carbonic inclusions also have CO2 partial homogenization temperatures (Th,CO2) of −28.3 to +23.7 °C, with most of the values clustering between +4.0 and +20 °C; all of these inclusions are homogenized into the liquid CO2 state. The densities range from 0.73 to 1.03 g/cm3. XCH4 of carbonic fluid inclusions ranges from 0.004 to 0.14, with most XCH4 around 0.05. In CO2–H2O fluid inclusions, Tm,CO2 values are recorded mostly at around −57.5 °C. The melting temperature of clathrate is 3.8–8.9 °C. It is suggested that the lowest trapping pressures of CO2 fluids would be 100 to ~400 MPa, on the basis of the Th,CO2 of CO2-bearing one-phase (LCO2) inclusions and the total homogenization temperatures (Th,tot) of paragenetic CO2-bearing two-phase (LCO2–LH2O) inclusions. For altered rocks, the Tm,CO2 of the carbonic inclusions has a narrow range of −58.4 to ~−57.0 °C, whereas the Th,CO2 varies widely (−19 to ~+29 °C). Most carbonic inclusions and the carbonic phases in the CO2–H2O inclusions are homogenized to liquid CO2 phases, which correspond to densities of 0.70 to ~1.00 g/cm3. Fluid inclusions in a single fluid inclusion assemblage (FIA) have narrow Tm,CO2 and Th,CO2 values, but they vary widely in different FIAs and non-FIAs, which indicates that there was a wide range of trapping pressure and temperature (P–T) conditions during the ore-forming process in late retrograde metamorphism after the metamorphism peak period. The carbonic inclusions in the Hamadi gold deposit are interpreted to have resulted from unmixing of an originally homogeneous aqueous–carbonic mixture during retrogress metamorphism caused by decreasing P–T conditions. CO2 contributed to gold mineralization by buffering the pH range and increasing the gold concentration in the fluids. © 2017, Canadian Science Publishing. All rights reserved.

Wu G.,CAS Institute of Geology and Geophysics | Liu J.,CAS Institute of Geology and Geophysics | Zeng Q.,CAS Institute of Geology and Geophysics | Liu M.,Tianjin North China Geological Exploration Bureau | And 3 more authors.
Earth Science Frontiers | Year: 2014

Shuangjianzishan Pb-Zn-Ag deposit is located at the central-south part of the Great Hing'an Range, which was a newly discovered super large scale deposit. Based on the alternate cross relationship and microscopic study, the mineralization process could be broken down into 4 stages: (I) quartz-sphalerite stage, (II) sphalerite-galena-silver mineral stage, (III) quartz-silver mineral stage, and (IV) pyrite-carbonate stage. Silver mineralization was developed in each stage except the last one; II and III were the main stages. During the stages of I and II, the silver minerals exclusively occurred as drops and anhedrons inside the galena, indicating that there was a strong genetic relationship between them. By contrast, the silver minerals of stage III were infilled between quartz grains or coated by quartz. Silver minerals mainly are polybasite, canfieldite, aguilarite, pyrargyrite, freibergite, argentite, kustelite and native silver; the mineralization process showed an evolution trend from complicated sulfosalt to elementary substance. The diameters of silver minerals in stage III are too small to liberate, average below 20 μm, which is the biggest obstacle to increase the recovery rate. If the flotation-cyanide process is adopted, the recovery rate of silver could be increased, and, besides, the minor gold mineral could be leached. On the basis of mineralogical signatures, we also dig into the relationship between silver and lead.

Li H.,China University of Geosciences | Li H.,University of Sichuan | Zhou Z.,China University of Geosciences | Li P.,University of Sichuan | And 7 more authors.
International Geology Review | Year: 2016

The eastern segment of the Central Asian Orogenic Belt is traditionally called the Xingan Mongolia Orogenic Belt (XMOB). Ordovician intrusive rocks exposed in the XMOB, from north to south, are the Abaga-East Ujimqin Qi-Duobaoshan belt, the Sonid Zuoqi-West Ujimqin Qi belt, and the Damaoqi-Baimaimiao-Tulinkai belt, respectively. Zircon U-Pb dating and geochemical data are presented for the intrusive rocks in East Ujimqin Qi and West Ujimqin Qi, Inner Mongolia. The intrusive rocks from East Ujimqin Qi consist of gabbro, diorite, and granodiorite. LA-MC-ICP-MS zircon U-Pb ages range 446 to 461 Ma. Geochemical data suggest that the gabbros and diorites from East Ujimqin are a tholeiitic series, both of arc-related and N-MORB (mid-ocean ridge basalt) signature, indicating a back-arc basin setting. The granodiorites have a shoshonitic series and arc-related signature. Rare earth element (REE) patterns and trace element characteristics suggest gabbros, diorites, and granodiorites are petrogenetically correlated. These intrusive rocks from East Ujimqin Qi have high light REE, Th, and U concentrations, suggesting the effect of middle-upper continental crustal contamination. Major oxides display positive or negative correlations, with increasing MgO or SiO2, indicating that fractional crystallization occurred during magma evolution. Geochemical data of diorite from West Ujimqin Qi indicate a tholeiitic series, arc-related signature. Zircon U-Pb dating yielded an age of 441.8 ± 1.5 Ma. Integrated with the regionally exposed Mid-Late Ordovician plutons and metasedimentary strata, we concluded that the northward subduction of the Palaeo-Asian Ocean (PAO) that occurred beneath the southern margin of the South Mongolian Micro-continent along the Sonid Zuoqi-Xilinhot gave rise to early Palaeozoic igneous rocks from the Abaga-East Ujimqin Qi-Duobaoshan and the Sonid Zuoqi-West Ujimqin Qi belts. Southward subduction beneath the North China Craton generated the Damaoqi-Baimaimiao-Tulinkai belt. The results support the bidirectional subduction model of the PAO in the early Palaeozoic. © 2016 Taylor & Francis.

Zhai L.,No.1 Geological Surveying Party | Ye H.-S.,Chinese Academy of Geological Sciences | Zhou K.,Geological Society of China | Meng F.,China University of Geosciences | Gao Y.-L.,Tianjin North China Geological Exploration Bureau
Geological Bulletin of China | Year: 2012

The Miaoling gold deposit in Songxian County of Henan Province is located in the Xiong'ershan-Waifangshan area on the south margin of North China craton. The ore deposit is hosted in the Mesoproterozoic volcanic rocks of Xiong'er Group, along a NS-trending fracture zone. Ore bodies occur in layered and lenticular forms, and ores have disseminated and stockwork structure with anhedral fine-grained texture and replacement texture. Hydrothermal alterations of the wall rock include silicification, K-feldspathization, sericitization, pyritization etc. Mineralizations show multi-stage characteristics and the gold deposit is of the fracture zone altered rock type. 40Ar-39Ar plateau age and isochron age of K-feldspar are respectively 121.6 Ma ± 1.2M a and 117.0 Ma ± 1.6 Ma, indicating that the ore deposit was formed in Early Cretaceous, identical in age with Qiyugou, Yaogou and other gold deposits in Xiong'ershan area. They therefore may be products of structure-magma-fluid activity in Early Cretaceous.

Li H.,China University of Geosciences | Zhang D.,China University of Geosciences | Zhou Z.,China University of Geosciences | Liu C.,China University of Geosciences | And 3 more authors.
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2016

Hexigten Qi is located to the north of Xar Moron River, tectonically on the south margin of Xilinhot massif. The authors conduct the analysis on the detrital zircon LA-ICP-MS U-Pb dating for the metasiltstones of Linxi Formation from a ca.5 km outcrop in the northeastern Hexigten Qi. The samples yield 4 groups of ages principally at: 258-298 Ma (peak at 285 Ma), 377-474 Ma (peak at 430 Ma), 1261-1727 Ma, and 1853-2513 Ma. Besides, two zircons yield the age of 321 Ma and 937 Ma respectively. Zirons aged 258-298 Ma show oscillatory zones in CL images, reflecting the magmatic events in Late Paleozoic along Xing'an-Mongolia orogenic belt. Zircons with 377-474 Ma ages are featured by both magmatic and metamorphic origins, suggesting that the provenances of Linxi Formation in Hexigten Qi probably were from Ordovician-Devonian magmatic and Paleozoic metamorphic rocks. Zircons yielded ages of 1261-1727 Ma are dominated by magmatic zircons, with some metamorphic zircons; indicating that the Mesoproterozoic magmatic and metamorphic rocks are also the provenances of Linxi Formation. Most of the Zircons aged 1853-2513 Ma are of magmatic origin, showing the old age information from North China Craton (NCC). The youngest age from this metasiltstone is 258 Ma, which constrains the deposition age of Linxi Formation to Late Permian. The broad scope of ages reflects the tectono-magmatic events both in NCC and Xing'an-Mongolia orogenic belt, and indicates that Linxi Formation has two provenances, and also implies that NCC and Siberia plate had amalgamated before Linxi Formation deposited. © 2016, Jilin University Press. All right reserved.

Jia B.J.,Zhejiang Institute of Geology and Mineral Resources | Jia B.J.,Hubei University | Chen Z.G.,Tianjin North China Geological Exploration Bureau | Chen Z.G.,China University of Geosciences | And 4 more authors.
Future Communication Technology and Engineering - Proceedings of the 2014 International Conference on Future Communication Technology and Engineering, FCTE 2014 | Year: 2015

The Panjia large-middle scale Polymetallic deposit is newly discovered in Zhejiang Province in China. In this paper, five molybdenite samples were collected from Datongkeng ore section of Panjia Ming Area for Re-Os compositional analyses and Re-Os isotopic dating.We got an isochron age of 142.88±0.78 Ma (2σ) with an initial187Os of 0.02±0.48 (MSWD=1.3). The age reveals that Panjia Deposit formed in a period of the tectonic transition of large-scale lithosphere, and the period is also an outbreak period of mineralization in southern China. © 2015 Taylor & Francis Group, London.

Wang X.,Chinese Academy of Geological Sciences | Yang Z.,Chinese Academy of Geological Sciences | Chen Y.,Chinese Academy of Geological Sciences | Hu J.,Tianjin North China Geological Exploration Bureau | And 3 more authors.
Global and Planetary Change | Year: 2015

A detailed environmental magnetic investigation in conjunction with geochemical, bulk grain size and redness analyses of late Early to early Middle Pleistocene loess-paleosol sequences at the Jiuzhoutai and Caotan loess sections has been carried out, aimed to explore the reliability of magnetic parameters as paleoclimatic proxies in the western Chinese Loess Plateau (CLP). The results show that magnetic enhancement of early- to mid-Pleistocene loess-paleosol sequences at both sites is not solely due to the neoformation of ultrafine magnetic particles through pedogenesis, but in the case of several loess layers (e.g., L8 and L9) is more attributed to the significant input of coarse-grained magnetic minerals associated with the advance of desert margin and/or with significant changes in local sediment input. Since the magnetoclimatological signals studied here are obviously controlled by both pedogenesis and wind vigor, measurements of magnetic susceptibility (χ) and saturation isothermal remanent magnetization (SIRM), both of which are responsive to both ultrafine pedogenic magnetic particles and eolian coarse-grained pseudo-single domain/multi-domain magnetic particles, could not provide unambiguous interpretation of the magnetic response to the East Asian summer monsoon intensity. In contrast, anhysteretic remanent magnetization (ARM) and the percentage of frequency-dependent magnetic susceptibility (χfd%), which are notably responsive to ultrafine magnetic particles, can aptly trace changes in the concentration of pedogenic magnetic particles and can therefore be used as reliable proxies of pedogenic intensity. The magnetic grain size dependent proxies, e.g., ARM/χ and ARM/Ms (Ms, saturation magnetization), geochemical indices (e.g., chemical index of alteration, Zr/Rb and Al/Si ratios), and bulk grain size records all exhibit concordant variations and are more straightforward proxies for addressing the East Asian monsoon variability. Therefore the combination of multi-parameter mineral magnetic, geochemical and grain size analyses is very useful for distinguishing, delimiting and correlating loess sequences, and for accurately deciphering their paleoclimatic signals embedded in the weakly weathered loess. As the classical precipitation-driven pedogenic model for magnetic susceptibility enhancement is not entirely applicable to the early- to mid-Pleistocene loess developed in the semi-arid western CLP, considerable caution should also be warranted in using magnetic susceptibility measurements alone in the quantitative reconstruction of paleoprecipitation. © 2015 Elsevier B.V.

Liu Z.R.,Beijing Institute of Technology | Tian Q.,Tianjin North China Geological Exploration Bureau
Applied Mechanics and Materials | Year: 2014

Wayaobao Formation of late Triassic, in Ordos Basin is composed of clastic rocks, such as grey green thick-bedding medium-coarse-grained lithic arkose, lithic feldspathic sandstone, fine-medium-grained lithic feldspathic greywacke, quartzose feldspathic sandstone, et al. Detailed study of Wayaobao Formation in Shenmu was carried out about lithology, sedimentary structures, biological characteristics, heavy mineralogy and trace element characteristics, then a conclusion was drawn that Wayaobao Formation in Shenmu, Ordos Basin was fluvial deposit. © (2014) Trans Tech Publications, Switzerland.

Wang Z.,Tianjin North China Geological Exploration Bureau | Guo P.,Tianjin North China Geological Exploration Bureau | Duan H.,Tianjin North China Geological Exploration Bureau
Geological Engineering and Mining Exploration in Central Asia - Proceeding Source: The XVIII Kerulien International Conference on Geology, KICG 2013 | Year: 2013

The genesis of Kalagailei copper polymetallic deposit in Zhaosu is the volcanic hydrothermal type in Nalati Metallogeny Belt, Xinjiang, which is the first characterized by copper deposit mainly, associating with cobalt, molybdenum, gold, galena, zinc etc. The deposit is hosted the volcanic strata of Dahalajunshan Formation of Low Carboniferous Series; copper orebodies occur in ductile shear belt which distributes NW direction; the wall rock is greenschist facies epimetamorphic rock mainly. The characteristic of sulfur isotopic composition of the deposit indicates that source of sulfur derives from mantle; hydrogen and oxygen isotopic composition of deposit shows that magmatic water have dominated hydrothermal fluid in the early stage, mixed with meteoric water in the late stage. This paper summarizes the geological characteristic and regularity of mineralization of deposit, and establishes metallogenic model of the deposit, it will have a great meaningful guidance to the next stage geological exploration.

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