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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.

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

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

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

Cerium anomaly and cerium thermodynamics in the sea water

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Acta Oceanologica Sinica 1994年第3期13卷 389-400页

作者： Wang Yunliang and Zang Desen(The Third Department,chengdu University of Technology, chengdu 610059, china)

Cerium anomaly in a marine carbonatite could be used as an indicator of redox condition in the paleosea- water. The bottom sea water of the Angola Basin and the Brazil Basin (SOuth Atlantic Ocean) was anoxic duringCretaceous period. At about 58×106-54×106 a BP, the sea water of the South Atlantic Ocean became oxidizedcondition which was similar to that of the modern Atlantic Ocean. This paper presents a new cerium redox thermodynamic equation which could explain the long-standing problems, such as the different characteristics of the ceriumanomalies in the sea water and river water and why there are positive cerium anomalies in the surface sea water,*** reveals that at 58×106-54×106 a BP, the plates of Africa and South America were separatedfrom each other thoroughly and the unified Atlantic Ocean took shape. We suggest that the Alpine and Himalayanmovements were in synchronism.

关键词： Cerium anomaly carbonate thermodynamics

Anti-scourability of purple soil on hillslopes with different land uses

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Science china(Technological Sciences) 2003年第z1期46卷 133-141页

作者： ZHANG Jianhui, LIU Gangcai, NI Shijun, ZHU Bo & GE Fanglong Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, chengdu 610041, china chengdu University of Technology, chengdu 610059, china Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China chengdu Univ Technol Chengdu 610059 Peoples R China

A large-scale flume (40 cm×10 cm×10 cm) was used to determine soil anti-scourability of 4 different land uses of purple soil in hilly areas of Sichuan, china under artificial removal of vegetation to examine the effects of land uses on sediment production by runoff. The results showed that soil anti-scourability declined with the increase of slope gradients in the form of power function, but there was a significant difference in the effects of slope gradients on anti-scourability between different land uses. The ratio of the mean values of soil anti-scourability was 1︰2.2︰2.5︰3.6 for forest land, new waste pasture, old waste pasture, crop land respectively, indicating that forest and grass use can significantly improve soil anti-scourability. Compared with the observations from the runoff plots located at the same sites in this region, an inconsistent result was found between anti-scourability and anti-erodibility in hilly areas of Sichuan. Essential causes of the differences in soil anti-scourability were further discussed based on analyzing the influence of inherent soil characteristics induced by different land uses on soil anti-scourability.

关键词： sediment yield, soil anti-scourability, land use, vegetation, purple soil.

The discovery of zinccopperite in a porphyry-copper deposit and its genetic significance

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Chinese Science Bulletin 1999年第S2期44卷 37-38页

作者： XIAO Yuanfu, SUN Yan, LU Yan, WANG Jiangzhen and WEN Chunqi chengdu University of Technology, chengdu 610059, china chengdu University of Technology Chengdu 610059 China

1 Geological features in the deposit THE Xifanping porphyry is located in the Yanyuan-Lijiang fault block at the southern margin of theYangtze massif. Only the Upper Permian Leping Formation and the Lower Triassic Qingtianbao Formation are exposed in Yanyuan County, Sichuan Province. The main ore-bearing rock body (No. 80) is anear-equant irregular complex stock, about 900 m long from east to west and 720 m wide from north tosouth. The bulk part consists of megaphyric biotite-quartz monzonitic porphyry. The commercial orebodylies in the No. 80 rock body and its surrounding country rocks, an N-S-elongated irregular lens-shapeddeposit. The orebody is controlled by the K-feldspar-biotite and quartz-sericite alteration zones. It consists mainly of disseminated and veinlet-disseminated ores.

关键词： zinccopperite alloy mineral quartz monzonitic porphyry Xifanping Yanyuan County.

FINITE STAIN MEASUREMENT AND SHORTENING ANALYSIS IN THE NORTHERN MARGIN OF QINGHAI—TIBET PLATEAU

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地学前缘 2000年第S1期7卷 149-150页

作者： Huang Jijun, Yi Haishen, Lin Jinhui, Liu Yuanchao(chengdu University of Technology,chengdu 610059, china)

Finite strain patterns of rocks The structural styles and crustal shortening in the northern margin of Qinghai—Tibet plateau are examined by systematic finite strain measurements. The finite strain patterns in this area are of following characteristics:① The orientation of & principal axes of strain ellipsoid varies regularly in regard to different tectonic locations. In fact, most of the measured X axes are parallel to the regional structure lines, striking east\|west or approximately east\|west with some X axes trending northeast\|southwest. The measured Z\|axes are approximately at right angle to the regional structure lines, trending north\|northeast or north\|northwest.② The Flinn parameter k is higher in the northern and southern margins of the basin than that in the basin center, indicating that the margins of basin experienced extensional strain and the middle of basin undergo strain.③ Rocks of different age possess different strain state and show k value of 1～2 for Tertiary rocks, 3～4 for Jurassic—Cretaceous rocks. The k value of the basement rocks is the highest of all.

关键词： Qinghai—Tibet Plateau finite crustal shortening balanced section