Gao Y.-B.,Xian Institute of Geology and Mineral Resources |
Gao Y.-B.,Changan University |
Li W.-Y.,Xian Institute of Geology and Mineral Resources |
Li K.,Xian Institute of Geology and Mineral Resources |
And 8 more authors.
Northwestern Geology | Year: 2012
The small intrusions consist of oligoclase granites are closely related with W-Sn mineralization in Baiganhu-Jialesai mineralization belt. The results of LA-ICP-MS U-Pb isotope dating show that oligoclase granite containing tungsten and tin ores was formed in 429. 5±3. 3 Ma. The ∈Hf (t) values of oligoclase granite vary from -11. 05 to 7. 40 with average of -1. 26, and the peak value of T2DM vary from 944 Ma to 2 111 Ma with average of 1 492 Ma. Because of crystal fractionation and fluid activity during the latest stage of magma evolution, geochemical data of oligoclase granite are characterized with rich Rb, Cs, Nb and Sn, depleted Ba, Zr, Hf, Th, Sr, Ti, V and La. The granites in Baiganhu-Jialesai mineralization belt were derived from the melting of ancient felsic crust because of mantle underplating during the extension environment, and oligoclase granite was formed in the latest stage of magma evolution. There are two oreforming stages in Baiganhu W-Sn deposit. In the first stage, during the intruding process of magmas containing tungsten and tin into wall rocks in early Silurian period, the batholith consist of monzonite granite was formed in deep, and small intrusions consist of oligoclase granites were formed in shallow. Then, the skarn-type and greisen-type tungsten ore bodies were formed in the top and contact belt of the small intrusions. In the second stage, after the fluid of latest magma evolution leaching metals from wall rocks, such as W and Sn, the quartz-veined tungsten ore bodies were formed along the fissures.
Wang F.,Jilin University |
Xu W.-L.,Jilin University |
Xu W.-L.,Wuhan University |
Gao F.-H.,Jilin University |
And 5 more authors.
Gondwana Research | Year: 2014
The Central Asian Orogenic Belt (CAOB) is a natural laboratory of the Phanerozoic accretionary orogen. The eastern section of the CAOB contains several microcontinental massifs, and it is unknown whether these massifs carry Precambrian basement. Here we present the results of U-Pb dating of detrital zircons from the Dongfengshan and Tadong groups in the eastern margin of the Songnen-Zhangguangcai Range Massif. The Dongfengshan and Tadong groups are subdivided, from bottom to top, into the Liangzihe, Huapigou, and Honglin formations, and the Lalagou and Zhudundian formations, respectively. Zircons from a two-mica quartz schist (sample HCM4-2) in the Liangzihe Formation yielded eight age populations, from 821 to 1802. Ma, whereas zircons from a two-mica quartz schist (sample 12HCM3-2) in the Huapigou Formation yielded four age populations (752, 803, 821, and 851. Ma). Zircons from a two-mica schist in the Lalagou Formation of the Tadong Group yielded two age populations (450 and 485. Ma), and zircons from a biotite-bearing plagioclase gneiss in the lower part of the Zhudundian Formation yielded five main age populations, from 551 to 1815. Ma. Samples 11NNA5-1 and 11HNA10-1 from the upper layer of the Zhudundian Formation yielded six main age groups, from 749 to 948. Ma. These data, together with the ages of zircons within a tonalite that intrudes the Tadong Group and the overlying Chenming Formation, indicate the presence of a Precambrian terrane associated with sedimentation at various times during the Neoproterozoic, including at ~. 821-752, ~. 752-560, and ~. 750-516. Ma, on the eastern margin of the Songnen-Zhangguangcai Range Massif. The Dongfengshan and Tadong groups were previously thought to be Proterozoic, but our study reveals that they constitute a Neoproterozoic-Late Paleozoic tectonic mélange. In addition, the widespread occurrence of detrital zircons with ages of 0.75-0.95, 1.5-1.6, 1.8, and 2.4-2.5. Ga provides evidence of a Neoproterozoic magmatic event and the presence of remnant ancient basement material within the Songnen-Zhangguangcai Range Massif. © 2013 International Association for Gondwana Research.
Zhang Y.,Jilin University |
Sun J.-G.,Jilin University |
Chen D.,Institute of Geologic Survey of Jiangsu Province |
Xing S.-W.,Chinese Academy of Geological Sciences |
And 5 more authors.
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2012
The Tianbaoshan polymetallic ore field is composed of Xinxing lead-zinc deposit, Lishan lead-zinc-copper deposit and Dongfeng lead-zinc-copper-molybdenum deposit. Both Xinxing and Lishan are hosted in contact zone between Jurassic granodiorite, diorite and Paleozoic marine volcanic rocks-sedimentary rock and the Dongfeng deposit occurs in rock bodies. The research on the geological features of these ore deposits shows that the Xinxing lead-zinc deposit is featured by filling of quartz sulfide in breccia pipe, similar to alteration characteristics of the mesothermal magmatic ore deposit; Dongfeng lead-zinc-copper-molybdenum deposit develops disseminated sulfide orebodies, quartz sulfide veins and molybdenite-quartz vein, showing characteristic of contact metasomatic-hydrothermal deposit; while a lot of magnetite, galena, sphalerite and other metal sulfides are found in Xinxing lead-zinc deposit, which suggests it be a representative contact metasomatic skarn deposit. Based on the research of fluid inclusions in quartz from main mineralizing stages and late ore-forming stage, it can be concluded that ore-forming process of the Xinxing deposit can be divided into three stages, quartz-pyrite, quartz-sphalerite-galena-chalcopyrite and quartz-carbonate. Homogenization temperatures of fluid inclusion formed in these three atages are 270-340°C, 190-260°C, 130-160°C, respectively. The salinity(w(NaCl)) of the inclusion changes from 0.62% to 9.86%, the density from 0.37 g/cm3 to 1.00 g/cm3 and the pressure from 37.31 MPa to 87.69 MPa. Laser Raman spectroscopy analysis of the fluid inclusions reveals they mainly consist of CO2 and H2O, with minor CH4 and N2. The mineralization of the Dongfeng deposit went through three stages: quartz-molybdenite(280-337°C), quartz-sphalerite-galena-chalcopyrite(200-260°C) and quartz-carbonate(101-190°C), salinity and density of fluid inclusions for Dongfeng deposit range from 7.16% to 23.95%, and from 0.96 g/cm3 to 1.12 g/cm3, respectively, with the pressure raging from 28.23 MPa to 56.64 MPa, and analysis from Laser Raman spectroscopy shows the major compositions in the inclusions is H2O. The mineralization of the Lishan lead-zinc-copper deposit can be divided into three stages, they are magnetite-quartz(210-240°C), quartz-galena-sphalerite-chalcopyrite(170-200°C) and quartz-carbonate(126-160°C), salinity and density of fluid inclusions from that deposit range from 2.07% to 9.47%, and from 0.89 g/cm3 to 0.92 g/cm3, respectively, with the pressure of 33.88-59.72 MPa, the study on Laser Raman spectroscopy showes that the component of fluid inclusions is mainly composed of CO2 and CH4. Combined with the geological features of ore deposit, properties and sources of the metallogenic fluids, the metallogenic model of the Tianbaoshan polymetallic ore field has been constructed.
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.
Yang J.,Jilin University |
Jiang Q.,Jilin University |
Zhang H.,Institute of Geological Survey of Jilin Province |
Li X.,Institute of Geological Survey of Jilin Province
2011 International Conference on Remote Sensing, Environment and Transportation Engineering, RSETE 2011 - Proceedings | Year: 2011
Based on traditional Mineralization information extraction technology, use of spectral angle mapping method (SAM) and support vector machine (SVM) method, alteration information extraction are used in Inner Mongolia, Ulan Chubb. First, preprocessing the original ASTER remote sensing image, and then study of the ore-related alteration of geological, in view of the different altered information uses the spectral Angle mapping method of selecting the training sample. Second, using SVM method to solve optimal hyperplane, then determine the decision function, establish of forecasting model. Lastly, generalizing promotion recognition to identify other samples to get alteration of information. Compared Alteration of the information extracted and the original geological data found consistent with the data. View from the field investigation, found in varying degrees of mineralization, and get a good effect. © 2011 IEEE.