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Vertical zoning model of fluorite ore-bodies in Zhejiang

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Chinese Science Bulletin 1999年第S2期44卷 73-74页

作者： ZHANG Shouting and XU Zhanzhang chengdu Univershty of Technology, chengdu 610059, China chengdu University of Technology Chengdu 610059 China

THK fluortite in Zhejiang Province is well known. However, the known outcrop mines have been graduallyexhausted by the exploiting over a long time. It has been a task of top priority to explore blind *** on the vertical zoning model will be very important and useful in the exploration for blind fluoriteore-bodies. 1 Genetic characteristics of fluorite deposits The fluorite deposits in Zhejiang Province are typical vein filling deposits. The minerals forming theores and the alterations of the wall rocks are all relatively simple. Studies show that the ore-forming materials （F and Ca etc. ） mainly come from the Chencai Group metamorphic rocks and the J3-K1 series vol-

关键词： fluorite ore bodies vertical zoning model. Zhejiang.

Emergency assessment of seismic landslide susceptibility: a case study of the 2008 Wenchuan earthquake affected area

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 207-217页

作者： Tang Chuan,Zhu Jing and Liang Jingtao State Key Laboratory of Geo-Hazard Prevention,chengdu University of Technology,chengdu 610059,China Professor Associate Professor Graduate Student State Key Laboratory of Geo-Hazard Prevention Chengdu University of Technology Chengdu 610059 China

The 8.0 Mw Wenchuan earthquake triggered widespread and large scale landslides in mountainous regions. An approach was used to map and assess landslide susceptibility in a given area. A numerical rating system was applied to five factors that contribute to slope instability. Factors such as lithology, topography, streams and faults have an important influence as event-controlling factors for landslide susceptibility assessment. A final map is provided to show areas of low, medium, and high landslide susceptibility. Areas identified as having high landslide susceptibility were located in the central, northeastern, and far south regions of the study area. The assessment results will help decision makers to select safe sites for emergency placement of refuges and plan for future reconstruction. The maps may also be used as a basis for landslide risk management in the study area.

关键词： landslide susceptibility GIS Wenchuan earthquake Qingchuan area

Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, Sichuan, China: Implication for ore genesis

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Science China Earth Sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1,2 & PAN Guitang2 1. Geoscience College, chengdu University of Technology, chengdu 610059, China 2. chengdu Institute of Geology and Mineral Resources, chengdu 610082, China 1. Geoscience College Chengdu University of Technology Chengdu 610059 China 2. chengdu Institute of Geology and Mineral Resources Chengdu 610082 China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, Sichuan Province, China. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in China. In a previous study by the first author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.

ISOTOPIC GEOCHRONOLOGY OF GRANITOIDS FROM THE NORTHWESTERN TIBET

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地学前缘 2000年第S1期7卷 215-216页

作者： Fan Ranxue (chengdu University of Technology, chengdu 610059,China)

This study area is located in the western North Tibetan Plateau, lying between the western Kunlun Mountains to the north and the Gangdise Mountains to the south, and covers an area of about 230000km\+2. Granitoid rocks occur widely in the area and mainly consist of huge intermediate\|acid intrusive rock\|bodies, which locally are accompanied by ultrabasic to basic *** granite bodies from the locations were chosen for this study. Determinations of U\|Pb age on zircon and Rb\|Sr age on whole rock or mineral of these rock units were made using a Finnigan MAT\|261 mass spectrometer fitted with multi\|collector. The total procedural Pb,Sr blank were always in the 2～4 ng range and insignificant in comparison to the sample(milligram range). K\|Ar data were previously published and are reported again here in order to compare them with the Pb and Sr results. The results for the eight granite bodies reveal a complex age pattern. This area may be divided on the basis of these radiometric dates into 5 rock zones. These zones defined are, from north to south, the southern Kunlun, the Qiangtang, the Anglonggangri, the Gangdise and the Himalaya rock zones.

关键词： North Tibet granitoid isotopic geochronology

Geo-engineering Lessons Learned from the 2008 Wenchuan Earthquake in Sichuan and Their Significance to Reconstruction

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Journal of Mountain Science 2011年第2期8卷 176-189页

作者： HUANG Runqiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 Sichuan China

The 2008 Wenchuan earthquake in Sichuan of China was the result of quake-triggering along an active several hundred-kilometer-long fault. The subsequent landslides and debris flow geohazards are dominating factors in planning post-disaster recovery and rebuilding. This paper presents recommendations for coping with large-scale geohazards and disasters. It is essential to establish a national emergency management system for huge scale catastrophe and earthquake precursor identification. Town construction must be kept away from active faults, especially to improve town safety in areas with high risk of seismic and geological hazards, and it is important to improve geohazard investigation and remediation for mountain areas that have become loosened by earthquake activity. Geological factors must be better understood to reduce direct and secondary risks and effects of earthquakes. Site selections for public relocation require clear and informed analysis of geological and social risk reduction, so that relocation, infrastructure reconstruction, and commemorative relic-sites can be protected.

关键词： Wenchuan Earthquake Geohazard Reconstruction

The Tectonic and Climate Change Across the Oligocene-Miocene Boundary in Northern Tibetan Plateau

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地学前缘 2009年第S1期16卷 272-273页

作者： Zhiqiang Shi,Haisheng Yi Institute of Sedimentary Geology,chengdu University of Technology,chengdu 610059,China.

From the planktonic foraminiferal and nannofossil events across the Oligocene/Miocene boundary (OMB) to the major transient glaciation at this epoch boundary,Mi-l,the paleoclimate,stratigraphic and paleontologic events showed a prominent change across the ***,the previous work was mainly about the marine deposits,especially the ocean drilling ***,the continental strata,such as the alluvial and lacustrine sedimentation in

关键词： tectonic event paleoclimate Miocene-Oligocene boundary Tibetan Plateau

Taphofacies Models of Devonian in Longmenshan Area, Sichuan, China

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Journal of Earth Science 1999年第2期18卷 29-37页

作者： Chen Yuanren Wang Hongfeng Department of Geology, chengdu University of Technology, chengdu 610059

Taphonomy refers primarily to the study of processes between death and final burial of an organism or a group of organisms, including both taphonomic loss and taphonomic gain. Taphofacies refers to the taphonomic traits, which include the taphonomic attributes of all fossils and the lithologic features of their enclosing rocks. Taphofacies is different from lithofacies; as a taphonomic environmental setting or taphonomic condition, it is more useful than the stratigraphic body of rock. Based on the features of fossil preservation integrated with stratigraphic, sedimentologic and paleontologic evidence from Devonian of Longmenshan area, it is distinguished and described 11 taphofacies models. For convenience in the field, the name of each taphofacies is divided into taphonomic and lithologic traits. The spatial relations between each taphofacies and the taphofacies with the benthic assemblages 1-6 are discussed.

关键词： taphonomy taphofacies model Devonian Longmenshan Sichuan China.

Fluid inclusion and isotopic composition features of Erze gold-siderite deposit, Sichuan, China

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Chinese Science Bulletin 1999年第S2期44卷 65-67页

作者： ZHENG Minghua and YANG Zhengxi Institute of Ore Geology, chengdu University of Technology, chengdu 610059, China Institute of Ore Geology Chengdu University of Technology Chengdu 610059 China

1 Geological features of gold-siderite deposits THE Erze gold-siderite deposit is located on the southeast margin of Songpan-Ganzi fold belt. The strataoutcropped in the region consist of the Hasi group of Presinian, the Upper Sinian, the Cambrian-Ordovician, the Permian, the Triassic, and the Tertiary. The Erze gold-siderite deposit, together with the othergold occurrences discovered in the region, is restricted in the carbonates of the Upper Permian, which isstratabound. The ore-control carbonate formation of the Upper Permian is composed of thick bed and mediumthickness crystalline limestone, with thin bed marl and slate. The formation in the Erze was developed into a NW-SE open anticline. A series of nearly E-W trending fracture zones are found in and nearby theanticline axis area, palaeokarst caves are confined to the zones, and the gold-siderite orebodies are restricted in the caves. Over one hundred orebodies with various sizes have been defined in the area, of which the

关键词： fluid inclusion isotope Erze gold-siderite deposit Sichuan.

High geo-stress distribution and high geo-stress concentration area models for eastern margin of Qinghai-Tibet plateau

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Science China(Technological Sciences) 2011年第S1期54卷 154-166页

作者： HUANG RunQiu,WANG YunSheng,WANG ShiTian & LI YuSheng State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection,chengdu University of Technology,chengdu 610059,China 1. State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection Chengdu University of Technology Chengdu 610059 China

High geo-stress and its engineering problems have severely affected the development of civil infrastructures in western China. The problems include high rock slope instabilities,rock burst,gas explosion and large-scale soft rock deformation in deep *** paper investigates the distribution of the high geo-stresses and the models of the stress concentration areas in the eastern margin of Qinghai-Tibet plateau so that a solid foundation can be formed to address the *** investigation is based on a comprehensive analysis of the previous research data of the eastern margin and uses remote sensing techniques,geophysics,geochemistry,and large scale geological surveying *** investigation has found that some special tectonic zones have high *** high geo-stresses are located at(1) the convergent boundary areas between two fault blocks with large strength differences,(2) the tectonic necks in front of active fault blocks,and(3) the intersection and/or termination areas of faults within the fault *** example for(1) is the north Qilian high geo-stress *** example for(2) is the Minshan high geo-stress area in the northwest ***,the investigation has summarized six basic models to characterize the high geo-stress concentration *** first one is the convergent stress concentration model at the boundary of two fault *** other five stress concentration modes are oblique fissures or intersecting areas,areas without lower velocity layer in the crust,areas of compression induced tensile cracking,tectonic wedge areas,and tectonic neck areas,respectively.

关键词： high geo-stress geo-stress concentration model regional geo-stress distribution Qinghai-Tibet plateau