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Significance of stress on mobilization of ore-forming materials

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Chinese Science Bulletin 1999年第S2期44卷 139-141页

作者： MA Rui and JIANG Qigang Research Center of Metamorphic Dynamics of changchun University of Science and Technology, changchun 130061, China Research Center of Metamorphic Dynamics Changchun University of Science and Technology Changchun 130061 China

METALLOGENIC processes represent migration and concentration of useful elements, which are controlled by a number of factors. Among varied geological factors, stress is very improtant. Stress could not only causethe fracture and deformation, but also is closely related to the mobilization and migration of ore-formingmaterials, especially for hydrothermal deposits. Varied experiments have been carried out to showthe above phenomenon. The sample is carbonaceous slate collected from the Taiyangding Group of the Nuo ’ ergai area,Sichuan Province. The rock is fresh, creckless, containing 40×10-9 of gold and high content of organiccarbon. Under a microscope, it is black. A group of state cleavage is observed, fine quartz and uniformily distributed carbonaceous materials. The quartz is<0.01 mm in diametre. Using high temperature

关键词： stress mobilization ore-formmg material.

RESEARCH PROGRESS OF ALTYN FAULT IN WESTERN CHINA

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地学前缘 2000年第S1期7卷 243-244页

作者： Ge Xiaohong, Ye Huiwen, Liu Yongjiang, Liu Junlai, Pan Hongxun, Ren Shoumai (College of Earth Sciences, changchun University of Science and Technology, changchun 130061,China)

As the northern boundary of Tibetan Plateau, the Altyn strike\|slip fault in western China has a very important implication to the tectonic division in the middle Asia continent, and has become a hot topic for the research on continental dynamics of Tibetan Plateau. During the research of our project funded by NSFC, we collected a sample of Caledonian mylonitized granite in the north of Dangjin pass and two samples of Jurassic meta\|sedimentary rocks in Qaidam gate fault\|valley and Geshi fault\|valley. The texture study shows that all samples were reformed by ductile deformation with undulating extinction and elongated quartzes. The metamorphic p\|T condition are estimated to be 350～500℃ and 150～450MPa They contain the syntectonic\|growing minerals such as white mica, chlorite, sericite and biotite etc. By dating these minerals, we obtain a group white mica 40 Ar/ 39 Ar isochronal age of 89 2～91 7Ma and a (46 6±6 4)Ma sericite 40 Ar/ 39 Ar apparent age. These data are very important to determine the strike\|slip age of Altyn *** 40 Ar/ 39 Ar age data (91～46Ma), we obtained, are reported for the first time in the researches of Altyn fault belt. The ages of 91～89Ma indicate that Altyn fault began to slip with slight metamorphism around late Jurassic. These ages are consistent with the ages of the collision between Kohistan\|Ladakh massif (northwestern India) and Eurasian continent at 102～*** suggests that the strike\|slip movement of Altyn fault should be related to the formation of the so\|called“Western tectonic joint" in Nepal\|western Kunlun area. The age of 46Ma should represent the overprint age of the tectono\|thermal event during main collision between Indian and Eurasian continents along the Yarlung Zangbo River. With the continent\|continent collision of Indian and Eurasian Plates, Altyn fault underwent Multi\|phase strike\|slip events in late Paleocene—Oligocene (37～35Ma), Miocene (22～20Ma), Miocene—Pliocene (8～6Ma), Pliocene (2 5Ma) and early

关键词： reconstruction geochronology tectonic Altyn fault

^40Ar/^39Ar dating of Daqingshan thrust

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Chinese Science Bulletin 2003年第24期48卷 2734-2738页

作者： LIU Zhenghong, XU Zhongyuan & YANG Zhensheng College of Earth Sciences, Jilin University, changchun 130061, China Correspondence should be addressed to Liu Zhenghong (e-mail: liuzhenghong@***) College of Earth Sciences Jilin University Changchun China

The Daqingshan thrust system, to the south of the Shiguai Mesozoic basin, is a complex system of top-to- the-north thrusting tectonic sheets. The thrust system has a complicated evolution due to multi-stage thrusting. In order to date the thrusting events, syntectonic muscovite and bio-tite grains are respectively analyzed with normal 40Ar/39Ar dating and laser 40Ar/39Ar dating, which yield 2 isochron ages, i.e. 193.74 3.88 Ma and 121.6 1.6 Ma. These ages suggest that faults within the Daqingshan thrust system formed dur-ing 2 stages of thrusting, one the early Indosinian and the other the late Yanshanian. The isotopic dating is consistent with field geological relations. Indosinan deformation is evi-denced by top-to-the-north thrusting, with the occurrence of a series of large-scale east-west trending thrust faults and folds, while the Yanshanian thrusting is characterized by top-to-the-NNW thrusting. It is superposed on and modifies early Indosinian thrust faults.

关键词： Ar 氩中生代云母同位素

The fragment of Paleo-Tethys ophiolite from central Qiangtang, Tibet:Geochemical evidence of meta-basites in Guoganjianian

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Science China Earth Sciences 2007年第9期50卷 1302-1309页

作者： ZHAI QingGuo1,2, LI Cai2 & HUANG XiaoPeng2 1 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2 College of Earth Sciences, Jilin University, changchun 130061, China Institute of Geology Chinese Academy of Geological Sciences Beijing China College of Earth Sciences Jilin University Changchun China

N-MORB-type metabasites are discovered in the Guoganjianian area, central Qiangtang, Tibet, which are mainly metagabbro with cumulate structure and metabasalt. The rocks are distributed nearly from west to east unconformably underlying the Wanghuling Group of upper Triassic. On the basis of geo- chemical analysis, we find that the content of SiO2 is 43.03%―53.42%, and TiO2 1%―2.67%, Al2O3 16.75%―21.52%, CaO 7.03%―11.13%, K2O 0.05%―0.38%; the REE pattern is slight depletion or flat, and the trace spider diagram is like that of N-MORB, so we consider that the metabasite was formed under the setting of mid-ocean ridge or adult back-arc basin, and it is the fragment of Paleo-Tethys ophiolite.

关键词： Qiangtang, metabasite, Paleo-Tethys, ophiolite

The Geological-Geophysical-Geochemical Exploration Model of the Nancha Type Gold Deposit in Tonghua Area, Jilin Province

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Global Geology 2001年第2期6卷 151-158页

作者： GUAN Jian (College of Earth Sciences, Jilin University, changchun 130061, P.R.China) College of Earth Sciences Jilin University Changchun 130061 P.R. China

The Laoling metallogenic belt is very important for precious and non-ferrous metal deposits in Jilin province, and the Nancha gold deposit found and explored in recent years in the metallogenic belt is the most representative one in the belt. The geological controls of the deposit,and the geophysical and geochemical ore searching indicators are summarized, and a synthetic exploration model, involving data from geology, geophysics and geochemistry and so on, is set up in the paper based on the study on the geological controls of the ores, on the measurement of geophysical properties of the ores and host rocks, on the observation of geophysical field around the mineralized district and on the research of the geochemical characte^ristics of the deposit. It is believed to be of significance to the exploration of the similar deposits in the metallogenic belt.

关键词： Nancha gold deposit exploration model S- shaped fracture zone geophysics geochemistry

Laser probe ^(40)Ar/^(39)Ar dating of mica on the deformed rocks from Altyn Fault and its tectonic implications,western China

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Chinese Science Bulletin 2001年第4期46卷 322-325页

作者： LIU Yongjiang, YE Huiwen, GE Xiaohong, CHEN Wen, LIU Junlai, REN Shoumai & PAN HongxunCollege of Earth Sciences, changchun University of Science and Technology, changchun 130061, China Graduate School, China University of Geosciences, Beijing 100083, China Laboratory of Isotopic Geochronology, Institute of Geology, Ministry of Land and Resources of China, Beijing 100037, China College of Earth Sciences Changchun University of Science and Technology Changchun China Graduate School China University of Geosciences Beijing China Laboratory of Isotopic Geochronology Institute of Geology Ministry of Land and Resources of China Beijing China

The samples of Caledonian mylonitized granite and Jurassic meta-sedimentary rocks were collected in the north of Dangjinshan Pass, Qaidam gate fault-valley and Gesi fault-valley. Detailed studies under the microscope and electronic microscope suggest that all the samples contain the syntectonic-growing minerals such as white mica, chlorite, sericite, biotite, etc. By dating these minerals, we got a group of 40Ar/39Ar laser probe isochronal ages of 89-92 Ma and apparent ages of (46.6±6.4) Ma. The ages ranging from 97 to 46 Ma were reported for the first time in the isotopic dating researches of the Altyn Fault The isochronal age group of (98-89) Ma indicates that a ductile strike-slip event, with low-grade metamorphism, began in late Cretaceous. This suggests that the strike-slip movement of the Altyn Fault should be related to the formation of the so-called west tectonic syntaxis in the Nepal-western Kunlun area.

关键词： Altyn Fault 40Ar/39Ar age strike-slip movement.

SHRIMP zircon U-Pb dating in Jingshan "migmatitic granite", Bengbu and its geological significance

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Science China Earth Sciences 2005年第2期48卷 185-191页

作者： XU Wenliang, WANG Qinghai, YANG Debin, LIU Xiaochun & GUO Jinghui College of Earth Sciences, Jilin University, changchun 130061, China Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China Institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing 100029, China College of Earth Sciences Jilin University Changchun China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing China Institute of Geology & Geophysics Chinese Academy of Sciences Beijing China

The petrographic characteristics of Jingshan "migmatitic granite" and the occurrence of the magmatic zircons indicate that the granite was formed by normal crystallization of felsic melts. All zircons in the granite have inherited cores and fine-scale oscillatory zoning rims of magmatic origin. It is realized that the granite was formed at 160.2±1.3 Ma through dating magmatic zircons. The generation of the granitic magma could be related to the lithospheric mantle and/or lower crust delamination after the ultrahigh pressure metamorphism (UHPM) in Triassic. Most inherited zircons yield the ages of 217.1±6.6 Ma, which is consistent with the peak UHPM in the Dabie-Sulu orogenic belt. Some of the inherited zircons (433-722 Ma) constitute a discordia line with the upper intercept age of 850+85/-68 Ma and a lower intercept age of 261+100/-140 Ma. These ages imply that the granite could be derived from the partial melting of the crustal materials of the South China Block that was intensively superimposed by the UHPM. The UHPM could be the reason for the major Pb loss at ±220 Ma.

关键词： zircon, U-Pb dating, migmatitic granite, geological significance, Bengbu.

A Sound Quality Objective Evaluation Method Based on Auditory Peripheral Simulation Model

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Journal of Bionic Engineering 2010年第2期7卷 199-208页

作者： Yinhan Gao~1,Jun Xie~2,Jie Liang~1,Xin Chang~3,Baojun Wu~2 1.Experimental Centre of Testing Science,Jilin University,changchun 130022,P.R.China 2.College of Instrumentation & Electrical Engineering,Jilin University,changchun 130061,P.R.China 3.Laboratory of Applications and Computations in Electromagnetics and Optics,Department of Electrical Engineering, University of Washington,WA 98195-2500,USA Experimental Centre of Testing Science Jilin University Changchun P. R. China College of Instrumentation & Electrical Engineering Jilin University Changchun P. R. China Laboratory of Applications and Computations in Electromagnetics and Optics Department of Electrical Engineering University of Washington Seattle USA

Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on sound wave *** method employs the artificial head technique, in which the head related transfer function was taken into account tothe outer ear simulation ***, a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical *** the auditory peripheral simulation model was built, which mimicsthe physiological functions of the human hearing, simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory ***, performance comparison was made between the proposed SQOEmethod and ArtemiS software, and the verifications of subjective and objective related analysis were *** show thatthe proposed method was economical, simple, and with good evaluation quality.

关键词： sound quality objective evaluation auditory peripheral simulation model artificial head head related transfer function

Virtual Field Geologic Trip System

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Global Geology 2003年第2期8卷 203-207页

作者： Jian Wang, Linfu Xue, Xiaojun ZhouCollege of Earth Sciences, Jilin University, changchun, 130061 China College of Earth Sciences Jilin University Changchun 130061 China

Virtual Field Geologic Trip System (VFGTS) constructed by the technique of visualization can efficiently present geologic field information and widely used in the field of geologic education. This paper introduces the developing thinking of VFGTS and discusses the main implement processes. Building VFGTS mainly includes systemically gathering of field geological data, the building of virtual geological world, and displaying of virtual geologic world and human-computer interaction.

关键词： Virtual Field Geologic Trip System, the technique of 3D visualization, 3D geological world, 3D graph ic engine