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Sun Z.,National Geological Library of China | Fan J.,China Aerospace Geophysical Survey & Remote Sensing Center for Land and Resources | Wang R.,China Zhengyuan Geomatics Co. | Zhao H.,China Aerospace Geophysical Survey & Remote Sensing Center for Land and Resources | And 3 more authors.
Geological Bulletin of China | Year: 2015

Subsidence is a serious environmental geological problem in China and even in the whole world. Synthetic Aperture Radar Interferometry (InSAR) is being developed as a main method for subsidence monitoring. Many geoenvironmental conditions of Jakarta are similar to those in Chinese coastal cities such as Shanghai and Guangzhou. As Jakarta is an important city on the 21st-Century Maritime Silk Road, the research on subsidence monitoring methods in Jakarta can produce experience for the same work in Chinese coastal cities and can also provide valuable information for the 'One Belt, One Road' Initiative. Based on 12 scenes of 3mresolution TerraSAR-X images acquired between June 2010 and March 2011, the authors studied and applied Small BAseline Subsets (SBAS) and 2-pass differential InSAR (DInSAR) methods. On the average subsidence velocity map produced by SBAS, 5 subsidence cones, which are located in west, north and east Jakarta and the northern part of Bekasi City, can be identified, with the maximum velocity up to 9 cm/a. After analyzing the time series 2-pass DInSAR interferograms, it was found that the cone in the northern part of Bekasi City had remarkable non-linear character because its subsidence value could reach 6cm in 44 days between December 2010 and January 2011. It can be concluded that high resolution TerraSAR-X data and proper DInSAR methods can support the work of subsidence mitigation in Jakarta and the similar cities. © 2015, Science Press. All right reserved. Source

Zhang Y.,Chinese Academy of Geological Sciences | Xing S.-W.,Chinese Academy of Geological Sciences | Wang Y.,Chinese Academy of Geological Sciences | Ma Y.-B.,Chinese Academy of Geological Sciences | And 5 more authors.
International Geology Review | Year: 2014

The Chibaisong magmatic Cu-Ni sulphide deposit is located in Tonghua City, Jilin Province, in the eastern part of the northern margin of the North China Craton. The geological characteristics of the deposit have been investigated, and pyrrhotite Re-Os isotope dating has been utilized to constrain the age. Five pyrrhotite samples separated from the Chibaisong Cu-Ni sulphide deposit yielded a Re-Os isotopic isochron age of 2237 ± 62 Ma (mean squared weighted deviation = 1.13, n = 5), indicating that the only Palaeoproterozoic magmatic Cu-Ni sulphide deposit in China is the Chibaisong Cu-Ni sulphide deposit. The geodynamic setting during ore formation was related to the Liaoning-Jilin Palaeoproterozoic rift split. The Re-Os isotope analyses showed an initial 187Os/188Os ratio of 0.778 ± 0.033, and (187Os/188Os) i and γOs(t) values ranged from 0.7531 to 0.8013 (average 0.7734) and from 574 to 617 (average 592), respectively, indicating that abundant crustal material (5-10%) was mixed with the Cu-Ni sulphide ore system during magma ascent and ore formation. © 2014 Taylor & Francis. Source

Zhiqian G.,China University of Geosciences | Tailiang F.,China University of Geosciences | Qunan D.,National Geological Library of China | Xiaolan H.,China Huadian Green Energy Company Ltd
Journal of Petroleum Geology | Year: 2016

This paper presents outcrop, petrographic, geochemical, well log and seismic data which together characterise the third-order T7 8 unconformity located between the carbonate-dominated Lower Ordovician Penglaiba and Yingshan Formations in the Tarim Basin, NW China. Unconformities in Lower Palaeozoic carbonates in this basin are of increasing interest because major reserves of hydrocarbons have recently been discovered at the North Slope field (> 1000 × 106 brls oil and ∼ 3050× 108 m3 gas). The reservoir here consists of karstified Lower Ordovician carbonates bounded by a third-order unconformity. The T7 8 unconformity in Tarim Basin represents a short-term exposure surface (< 1 Ma) controlled both by sea-level changes and by palaeogeographic location within the basin, and the intensity of karstification varies laterally. The unconformity has had a major influence on porosity development in the underlying Penglaiba Formation carbonates. At two measured outcrop sections at the NW basin margin (Penglaiba and Shuinichang), dissolution porosity was observed in karstified and dolomitised carbonates below the T7 8 unconformity surface. A seismic profile shows the presence of reflection anomalies below the unconformity which are interpreted as karst-related palaeo-caverns. Geochemical data indicate that the T7 8 unconformity is associated with anomalies in stable isotope ratios and in heavy mineral and trace element profiles. Thus there are negative excursions in δ13C and δ18O ratios within the carbonate rocks immediately below the unconformity surface. Similarly, concentrations of major and trace elements such as Li, K, Ti, Rb, Th, Sr, V and Ni are significantly reduced in the underlying carbonates, while there is an anomalously high content of haematite-limonite. © 2016 The Authors. Journal of Petroleum Geology © 2016 Scientific Press Ltd. Source

Zhang Y.,Chinese Academy of Geological Sciences | Xing S.-W.,Chinese Academy of Geological Sciences | Song Q.-H.,Institute of Geological Survey of Jilin Province | Wang Y.,Chinese Academy of Geological Sciences | And 4 more authors.
Resource Geology | Year: 2015

Jilin Province in NE China lies on the eastern edge of the Xing-Meng Orogenic Belt. Mineral exploration in this area has resulted in the discovery of numerous large, medium, and small sized Cu, Mo, Au, and Co deposits. To better understand the formation and distribution of both the porphyry and skarn types Cu deposits of the region, we examined the geological characteristics of the deposits and applied zircon U-Pb and molybdenite Re-Os isotope dating to constrain the age of the mineralization. The Binghugou Cu deposit yields a zircon U-Pb age for quartz diorite of 128.1±1.6 Ma; the Chang'anpu Cu deposit yields a zircon U-Pb age for granite porphyry of 117.0±1.4Ma; the Ermi Cu deposit yields a zircon U-Pb age for granite porphyry of 96.8±1.1 Ma; the Tongshan Cu deposit yields molybdenite Re-Os model ages of 128.7 to 130.2 Ma, an isochron age of 129.0±1.6 Ma, and a weighted mean model age of 129.2±0.7 Ma; and the Tianhexing Cu deposit yields molybdenite Re-Os model ages of 113.9 to 115.2Ma, an isochron age of 114.7±1.2 Ma, and a weighted mean model age of 114.7±0.7 Ma. The new ages, combined with existing geochronology data, show that intense porphyry and skarn types Cu mineralization was coeval with Cretaceous magmatism. The geotectonic processes responsible for the genesis of the Cu mineralization were probably related to lithospheric thinning. By analyzing the accumulated molybdenite Re-Os, zircon U-Pb, and Ar-Ar ages for NE China, it is concluded that the Cu deposits formed during multiple events coinciding with periods of magmatic activity. We have identified five phases of mineralization: early Paleozoic (~476 Ma), late Paleozoic (286.5-273.6 Ma), early Mesozoic (~228.7 Ma), Jurassic (194.8-137.1 Ma), and Cretaceous (131.2-96.8 Ma). Although Cu deposits formed during each phase, most of the Cu mineralization occurred during the Cretaceous. © 2015 John Wiley & Sons, Ltd. Source

Zhang Z.,Chinese Academy of Geological Sciences | Xing S.,Chinese Academy of Geological Sciences | Ma Y.,Chinese Academy of Geological Sciences | Du X.,National Geological Library of China | And 3 more authors.
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2013

Hongtoushan Cu-Zn deposit is a typical VMS deposit in Northeast China. To reconstruct the history of the diagenesis and tectonic thermal activities of the area and to investigate the process of the metallogenesis by different approaches are vital to the studies of the deposit. The zircons from biotite-bearing plagioclase ampibolite, a typical host rock of Hongtoushan deposit, were studied to discuss the process of the mineralization of the deposit. The zircons are granular in shape and were formed during the emplacement of the calc-alkaline basalt of the area, the parental rock of the plagioclase ampibolite under this study. According to the results of the analyses in the paper, the zircons were formed at 2500 Ma which represents the age of the Hongtoushan deposit. The deposit was suggested to be formed in a back-arc basin shortly after Anshan movement during which ancient oceanic plates disappeared, continents collided, and granite emplaced. The related thermal activities were responsible for the high grade copper ore pillars in the deposit. Considering the ore-forming processes and the mechanism of the deposit, more attention should be paid to the following two aspects during the exploration of the copper deposit: 1) this type of deposit is hosted in the bimodal volcanic rocks of the greenstone belt; 2) the high grade VMS ores should be localized in the collision belt of continents of the Anshan movement. Source

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