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Zhang X.-F.,Tianjin Geological Mineral Testing Center | Chen B.,Tianjin Geological Mineral Testing Center
Northwestern Geology | Year: 2014

Ka'erqueka Cu deposit in Qinghai province has porphyry-skarn-hydrothermal metallo- genic characteristics of the series. The orefield is divided into three areas as A, B and C, among which area A is mainly porphyry mineralization, area B is mineralization of skarn type. Copper polymetallic deposit primarily originated in the contact area between granodiorite and porphyritic monzonitic granite and Cambrian-Ordovician Tanjianshan Group, that is skarn ore belt and porphyry copper deposit. By comparison of mineral assemblage and petrological geochemical characteristics, the porphyritic monzonitic granite of Area B in Ka' erqueka deposit is a product of the early stage of Caledonian subduction collision. Both porphyry mineralization in porphyritic monzonitic granite of Area A and skarn mineralization in granodiorite of Area B are products of subduction collision orogenic stage in late Triassic Indo-Chinese epoch, that produced a typical por-phyry deposit system, then superimposed on early mineralization in Caledonian period, and finally the larger copper molybdenum deposit was formed.

Wang J.-N.,Nankai University | Meng J.-W.,Tianjin Geological Mineral Testing Center | Yang F.-X.,Nankai University | Cai Z.,Nankai University | And 2 more authors.
Chinese Journal of Ecology | Year: 2015

The natural sedimentation method was employed to monitor airborne microbial concentration of different functional areas in Tianjin Economic-Technological Development Area (TEDA, Tianjin) from March 2012 to February 2013. The results showed that bacteria were pre-do-minant (76.5%), followed by fungi (19.4%) and sactinomyces (4.1%). Canonical ordination analysis was performed to elucidate the temporal and spatial distribution of urban airborne microbes. The results indicated that microbes had a dramatically spatial cluster based on urban function (five types of clusters), among which 46.0% of variation could be explained by first and second axis, with the highest microbial concentration in constructing and industrial area and the lowest in residence zone; on the other hand, microbes had a remarkable temporal cluster according to seasons (three clusters), in which 78.7% of variation could be interpreted by first and second axis with the highest microbial concentration in summer and the lowest in winter. Airborne microbial concentration had a significant positive correlation with temperature (P <0.01). The study showed that airborne microbial variation in temporal distribution was higher than that in spatial distribution, illustrating that the effect of seasonality was stronger than that of area function. In addition, the results revealed that PM10 concentration was positively correlated to SO2 concentration (P = 0.011) in TEDA, Tianjin, suggesting SO2-type smog in this area. © 2015, Editorial Board of Chinese Journal of Ecology. All rights reserved.

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