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.
Jia B.J.,Wuhan University |
Jia B.J.,Zhejiang Institute of Geology and Mineral Resources |
Zhou L.Y.,Zhejiang Institute of Geology and Mineral Resources |
Chen Z.G.,Tianjin North China Geological Exploration Bureau |
And 5 more authors.
Applied Mechanics and Materials | Year: 2014
Qinhang Metallogenic Belt is an important metallogenic zone of copper, iron, and precious metals deposits, in China. On the basis of absorbing and summarizing the achievements in the previous researches, 5 kinds of gold metallogenic series are summed up. One of the most important series is Gold Metallogenic Series Related to Dynamic Metamorphism, of which the deposits are mainly distributed around Shaoxing-Jiangshan deep fault belt and have the characters of large amount and big reserve. The gold ores of other metallogenic series types are mainly associated with Pb, Zn and Cu deposits. © (2014) Trans Tech Publications, Switzerland.
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.
Wu W.,Beijing Hydraulic Research Institute |
Wu W.,Water saving Engineering Research Center |
Chen W.,Tianjin North China Geological Exploration Bureau |
Liu H.,Beijing Hydraulic Research Institute |
And 7 more authors.
Irrigation and Drainage | Year: 2014
In this study, a dimensional analysis model for disc filters was developed based on hydraulic tests of 10 different types of disc filters together with structural parameters such as the inner diameter of the inlet/outlet pipe Db, the outflow path width Pw, outflow path depth Pb, disc width Dd, etc. The correlation coefficient Radj2 of the model was 0.990. The correlation coefficient between the measured and predicted values of the model was R2 = 0.967. The effects of structural parameter changes on the filter head loss were studied based on the typical physical structural parameters. The inlet/outlet inner diameter was found to have the greatest impact on the head loss. The effects on the head loss resulting from changes in the outflow path width and depth were not significant (P < 0.05). Therefore, when designing the flow path structure of disc filters, the head loss can be effectively minimized by increasing the inlet/outlet inner diameter, inflow path depth, and inner diameter of the disc filter element. In addition, a decrease in the outflow path width and depth can reduce the amount of pollutants entering the flow path without causing a significant increase in the head loss. © 2013 John Wiley & Sons, Ltd.