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Two new reinforcement techniques applicable in high steep slopes along the Chengdu-Lhasa Highway, Southwest China

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Science China(Technological sciences) 2003年第Z1期46卷 156-162页

作者： YANG ZhifaZHU Jiewang ZHANG Luqing, CUI Peng, LI Xiao & SHANG Yanjun institute of geology and geophysics,{3.,{4., China institute of Mountain Hazards and Environment,{3. and Ministry of Water Resources, Chengdu 61004., China chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

Anti-slide pile and anchoring hole are two types of reinforcement techniques popularly used in slope reinforcement. However, some defects of these two techniques are found in slope engineering practices. Utilizing higher tensile strength of pre-stressed structures, the authors devise two new types of slope reinforcement techniques, i.e. pre-stressed anchoring beam and pre-stressed anti-slide pile, in an attempt to overcome those defects of the existing techniques. These two new techniques are characterized by gathering multiple functions, e.g. engineering investigation, reinforcement, drainage, monitoring and strength supplement, so as to achieve high reinforcement efficiency, convenient checking, and higher ratio of function to cost. It is hoped that, if applying these two new techniques in remedies of landslide hazards along the Chengdu-Lhasa Highway, better reinforcement effects will be obtained.

关键词： rock slope, pre-stressed anchoring beam, pre-stressed anti-slide pile.

Carbon isotope ratios of C_(4. plants in loess areas of North China

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Science China Earth sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2,3. HAN Jiamao 2, ZHOU Liping3. XIONG Xiaogang4. TAN Ming2, WU Zhenhai5 & PENG Jun6 1. Department of Plant Nutrition, China Agricultural University, beijing 100094. China 2. {3. of geology and {3.,{4., beijing 100029, China 3. College of Environmental sciences, MOE Laboratory for Earth Surface Processes, Peking University, beijing 100871, China 4. {3. of Botany,{4., beijing 100093. China 5. Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712100, China 6. Network Center, China Agricultural University, beijing 100094. China Department of Plant Nutrition China Agricultural University Beijing China institute of geology and geophysics Chinese Academy of Sciences Beijing China College of Environmental sciences MOE Laboratory for Earth Surface Processes Peking University Beijing China institute of Botany Chinese Academy of Sciences Beijing China Northwest Sci-Tech University of Agriculture and Forestry Yangling China Network Center China Agricultural University Beijing China

Carbon isotope ratios (δ^(13.C) of 89 C_4.plant samples were determined fromthe loess area in North China. δ^(13.C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13.C values of C_4.plants show a slight decreasingtrend. The δ^(13.C values of C_4.plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3.species.

关键词： C4 plants, carbon isotope ratios, loess area.

Zijinshan-Bitian Cu-Au-Mo orefield, SW Fujian——An example of gold-rich PCS zoning

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chinese Science Bulletin 1999年第S2期44卷 134-135页

作者： QI Jianzhong~1, LI Zhaonai~2, ZHANG Dequan~3. FANG Xiheng~4.and XIAO Huiliang~1 1. Nanjing institute of geology and Mineral Resources, {3. {3. of Geological {4., Nanjing 210016, China 2. institute of geology, {3. {3. of Geological {4., beijing 10003., China 3. institute of Mineral Deposits, {3. {3. of Geological {4., beijing 10003., China 4. institute of geology, Ministry of Nuclear Industry, beijing 100013. China Nanjing institute of geology and Mineral Resources Chinese Academy of Geological Sciences Nanjing 210016 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China institute of geology Ministry of Nuclear Industry Beijing 100013 China

THE Zijinshan-Bitian Cu-Au-Mo orefield is spread to north of the Shanghang County, SW *** geological structure it is located at the plunging end of NE-trending Xuanhe anticlinorium, in the NE rim ofthe NW trending Shanghang volcano-sedimentary basin. Orefield basement is composed of the Archean-Middle Proterozoic low-grade metamorphic rock formations, containing marine basic metavolcanic sequenses. Lower Cretaceous subaerial volcanic rocks of andesite-trachy andesite-rhyolite composition fill inthe volcano-sedimentary basin. Pre-mineralization granitic batholith dated 14.Ma（Rb-Sr）and 157Ma（U-Pb） occupies the axial part of the plunging anticlinorium, which was regarded as crust-remelting typegranitoids. Mineralization-affiliated subvolcanic dacite porphyrite, co-volcanic granodiorite and quartzdiorite porphyrite （102.2 Ma（Rb-Sr）, Sr1 = 0.708 9） belong to syntactic type in genesis and

关键词： gold-rich porphyre copper system zoning Fujian Zijinshan.

New geological evidence of crustal thickening in the Gangdese block prior to the Indo-Asian collision

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chinese Science Bulletin 2003年第15期48卷 1604-1610页

作者： DING Lin & LAI Qingzhou institute of geology and geophysics,{3.,{4., China Correspondence should be addressed to Ding Lin (e-mail: dinglin@ ***) chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Recent mapping in the Gangdese block has revealed many leucogranites that are similar to those in the High Himalaya. These leucogranites formed at ~14. Ma as indicated by monazite Th-Pb ion-microprobe dating and cooled at ~13. Ma as indicated by muscovite 4.Ar/3.Ar dating. In conjunction with previous structural and paleogeographic studies, the new data indicate that the Gangdese block underwent crustal thickening and associated exhumation during ~14.-13. Ma. In this regard, the southern margin of Eurasia continent was comparable to the modern South American Altiplano-Puna plateau, the prime example of active ocean-continent subduction and associated thickened crust. Specifically, the early stages of crustal thickening and uplifting of the Gangdese block may result from subduction of the Neo-Tethyan Ocean. If the Tibetan Plateau would form by accretion of a series of blocks with thickened crust, an elevated topographic plateau similar to the Altiplano- Puna plateau had formed before collision between the Indian and Eurasian plates. Then the Tibetan Plateau would have quickly thickened, uplifted, and begun to extend soon after onset of the collision. Thus, the deformational mechanism of the Tibetan Plateau is not distributed shortening, but rather concentrating deformation within regions of thin crust between the accreted blocks.

关键词：地质学地壳增厚亚洲淡色花岗岩喜马拉雅山脉

The high-resolution climate recorded in the δ^(18)O of Porites lutea from the Nansha Islands of China

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chinese Science Bulletin 2001年第24期46卷 2097-2102页

作者： YU Kefu, CHEN Tegu, HUANG Dingcheng, ZHAO Huanting, ZHONG Jinliang & LIU Dongsheng (LIU Tungsheng)South China Sea institute of Oceanoiogy, chinese academy of sciences. Guangzhou 5103.1, China:geology and {3. institute. chinese academy of sciences, beijing 100029, China South China Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China geology and geophysics institute Chinese Academy of Sciences Beijing China

A Porites lutea core from Yongshu Reef of Nansha Islands covering 50 years growth history was ana-ly/ed for oxygen isotopic composition with monthly and seasonally resolution. The calibration of the δ18O with the instrumental temperature indicated that the coral δ18O is a good indicator for sea surface temperature (SST) and air temperature (t). It can be used to reconstruct the SST and air temperature of the Yongshu Reef sea area. In addition, the coral δ18O provides signatures for the intensity of the East Asia monsoon and it is a record for the activities of El Nino events. With the calibrated SST and air temperature formulas, the most recent fifty years SST and air temperature were reconstructed based on the coral δ18O, thus back up the understanding of the climate of Nansha Islands to 1950. far beyond the limit of the instrumental recording since September 1988. It was found that, in general, increasing 1℃ air temperature results in 0.24.decrease in skeletal δ18O.

关键词： Nansha Islands Porites lutea δ18O sea surface tem-perature East Asia monsoon.

Si-and alkali-rich melt inclusions in minerals of mantle peridotites from eastern China:Implication for lithospheric evolution

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Science China Earth sciences 2006年第1期49卷 43-49页

作者： FAN Qicheng1, SUI Jianli2, XU Ping2, LI Ni1, SUN Qian1 & WANG Tuanhua1 1. institute of geology, China Seismological Bureau, beijing 100029, China 2. institute of geology and geophysics, chinese academy of sciences, beijing 100029, China institute of geology China Seismological Bureau Beijing China institute of geology and geophysics Chinese Academy of Sciences Beijing China

Minerals of spinel- and garnet-facies mantle xenoliths entrained in Cenozoicbasalts from eastern China (North China, Northeastern China and Southeastern China coastal area)contains lots of melt inclusions. Studies on these melt inclusions show that the glass inclusionsare rich in SiO_2 (60%—68%) and alkalis (K_2O+Na_2O = 5%—11%, especially for K_2O) as well asvolatiles such as H_2O and CO_2 (2%—7%), which belong to dacites and andesites of the high-K calcicalkali series rocks with few shoshonites. High Al and Ca diopside in melt inclusion is the productof melt crystallization at high temperature and pressure, rather than the product ofdevitrification. Results show that these K-rich (in general K_2O > 3.) intermediate-acidic silicatemelt inclusions have characteristics of continent without a genetical link to host basalts and theirphenocrystic minerals. Thus, these trapped melt inclusions represent melts of Mesozoic lithosphericmantle-crust interaction and imply that the continental lithospheric mantle beneath eastern Chinahad undergone fragmentation and recreation processes during the Mesozoic and Cenozoic periods. Thisresult undoubtly provides important implication for the evolution of sub-continental lithospherebeneath eastern China. We propose that these Si- and alkalis-rich melts should be responsible forthe mantle chemical heterogeneity underneath eastern China.

关键词： Si- and alkali-rich melt inclusion, mantle peridotite, lithospheric evolution, eastern China.

2002:The extra-strong warm winter event in North Asia and its accompanying anomalous atmospheric circulation

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chinese Science Bulletin 2003年第10期48卷 1031-1033页

作者： WANG Huijun LASG, institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, China LASG Institute of Atmospheric Physics Chinese Academy of Science China

Features of an extra-strong warm winter event in North Asia in 2002 and its accompanying anomalous atmospheric circulation were studied through diagnosis on the atmospheric reanalysis data set. Results show that the winter of 2002 is of the warmest in the recent 54.years in North Asia, which was caused by both decadal scale and interannual scale variability. The interannual variability is proved to be as the main cause for the event, and it is related to the global scale atmospheric circulation anomalies, with the strongest of them in the Eastern Hemisphere and in the middle and high latitude region of the Southern Hemisphere.

关键词：大气环流亚洲北部高强度暖冬现象天气资料

Mesozoic-Cenozoic tectonic transition in Kuqa Depression-Tianshan,Northwest China:Evidence from sandstone detrital and geochemical records

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Science China Earth sciences 2005年第9期48卷 1387-1402页

作者： LI Zhong1, GUO Hong2, WANG Daoxuan3.& LIN Wei1 1. institute of geology and geophysics,{3.,{4., China 2. Tarim Oilfield Branch, CNPC, Korla 84.000, China 3. Hefei University of Industry, Tunxilu 193. Hefei 23.009, China institute of geology and geophysics Chinese Academy of Sciences Beijing Chin Tarim Oilfield Branch CNPC Korla China Hefei University of Industry Hefei Chin

Similar to compositional evolution of sandstone modes and detrital heavy minerals from different profiles in the Kuqa Depression, Northwest China, major element analysis of whole sandstones from the same profiles shows four discontinuous depositional interfaces or periods, respectively corresponding to Lower Triassic\Middle Triassic, Upper Jurassic\Lower Cretaceous, Lower Cretaceous\Paleogene and Miocene\Pliocene, and indicates five-phase evolution during Mesozoic-Cenozoic: (1) From the first to fifth phase, a depositional suite changes from maroon and coarse clastic, through grey-dark grey and fine, red and coarse, red-mottled, interlayered by gypsum, to brown and coarse clastic assemblages, accompanying detrital component evolution in unstable-stable-unstable-very unstable-very unstable assem- blages. It is indicated that carbonate and complex detritus gradually dominate in sandstones in post-Late Jurassic, with rapid reduction of compositional maturity. (2) For major element geo- chemical parameters of whole sandstones, CaO and Fe2 O * 3.MgO contents show a change sequence in high-low-high-higher-highest values, with rapid increasing in post-Late Jurassic. (3. Contra some aggregative indicators for weathering indexes of sandstone detrital component, Al2O3.(CaO+Na2O) and ln(Q/(L+CE)), show a change sequence in low-high-low-lower-lowest ratios, with rapid decreasing in post-Late Jurassic. It is found that sandstone samples of the first, second and later three phases may be distinguished from the A-CN-K and A-CNK-FM diagrams respectively. Therefore, in the Kuqa Depression-Tianshan, the most important discontinuous depositional interface recording paleotectonic and paleoclimatic transition occurred in Early Triassic\Middle Triassic and Late Jurassic\Early Cretaceous, respectively, and, however, tec- tonic differentiations of basin-range system finally result in distinct depositional systems but similar detrital weathering indexes across the Lower Cretaceous\Paleogene

关键词： Tianshan, Kuqa Depression, basin-range, depositional record, tectonic transition, Mesozoic-Cenozoic.

Monitoring Crustal Movement of the Coastal Zone in Eastern China with GPS Technique

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地球科学进展 2004年第S1期19卷 21-29页

作者： DING Ji-xin, YANG Zhi-fa, SHANG Yan-jun (institute of geology and geophysics,{3.,{4., China)

In this paper, various dominating factors affecting crustal movement of the coastal zone in eastern China are analyzed, and major characteristics of crustal movement are summarized. Subduction of the pacific plate and Philippine plate and southeastward "escape" of Qinghai-Tibet plateau are believed to be dominating factors affecting crustal movement of that zone. Undoubtedly, it is a best way to monitor this kind of large-scale crustal movement with GPS technique. The feasibility of monitoring crustal m...

关键词： GPS Coastal zone Eastern China Crustal movement.