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chinese science Bulletin 2002年第15期47卷 1292-1297页

作者： ZHANG Xiaohui, LI Tiesheng, PU Zhiping & WANG HuiResearch Center for Mineral Resources Exploration, institute of geology and geophysics, chinese academy of sciences, beijing 100101, china Guangzhou institute of Geochemistry, chinese academy of sciences, G Research Center for Mineral Resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

The Louzidian normal fault occurs as the eastern detachment fault of the Kalaqin metamorphic core complex. Field observations and microstructural analyses reveal that the Louzidian-Dachengzi ductile shear zone developed in its lower-plate was genetically related to sinistral strike-slips and extensional faulting. Two samples from this ductile shear zone yield 40Ar-39Ar plateau ages of 133 Ma (Bi) and 126 Ma (Kp), which are concordant with their isochron ages. The plateau age of 133 Ma (Bi) records the formation age of the ductile shear zone. The inconsistent relationship between the earlier strike-slip ductile shear zone and the later normal fault makes the Kalaqin Quasi-metamorphic core complex distinctive from Cordil-leran nietamorphic core complex. These ages provide important geochronological data for putting constraints on the formation age and genesis of such ductile shear zones.

关键词： 40Ar-39Ar age Sinistral strike-slip Louzidian-Dachengzi ductile shear zone Metamorphic core complex.

Cleaning of Chromate Manufacture Process

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 132-134页

作者： Xing Zou Yi Zhang(Applied science School, University of science and Technology beijing, beijing 100083, china)(institute of Engineering Chemistry and Metallurgy, chinese academy of sciences, beijing 100080, china) Applied science School University of Science and Technology Beijing Beijing 100083 China institute of Engineering Chemistry and Metallurgy Chinese Academy of Sciences Beijing 100080 China

Sodium chromate solubility is determined in the range of NaOH concentrations from 450 to 810 g/L andsolution temperatUres from 30 to 110℃. The optimized conditions to separate sodium chromate from NaOH inleached solution are resolved. It is first found the method to efficiently separate sbdium chromate from NaOH andsodium altuninate in crude sodium chromate. Bench-scale studies on the separating are performed. Finally, goodseparation results are achieved.

关键词： chromate separation clean process

Typical basin-fill sequences and basin migration in Yanshan, North china ——Response to Mesozoic tectonic transition

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science china Earth sciences 2004年第2期47卷 181-192页

作者： LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. institute of geology and geophysics, chinese academy of sciences, beijing 10002., china 2. china University of Geosciences, beijing 100083, chinaCorrespondence should be addressed to Li Zhong (email: lizhongd@***) 1. institute of geology and geophysics Chinese Academy of Sciences 100029 Beijing China 2. china University of Geosciences 100083 Beijing China

Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North china may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.

关键词： Yanshan, Mesozoic, basin-fill, paleocurrent, tectonic transition.

Occurrences of Permian radiolarians in central and eastern Nei Mongol(Inner Mongolia) and their geological significance to the Northern china Orogen

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chinese science Bulletin 2004年第24期49卷 2613-2619页

作者： SHANG Qinghua Nanjing institute of geology and Paleontology,chinese academy of sciences,Nanjing 210008,china institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of sciences,beijing 100044,china Nanjing institute of geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

The Zhesi (Jisu) Formation of the Middle Per- mian in Nei Mongol (Inner Mongolia) was commonly con- sidered to be a shallow marine sequence. Here I report the radiolarians found in the argillite bed of that formation in Zhesi and Xilinhot areas. This fact indicates a deep marine sedimentary facies persisted during the Middle Permian, and suggests that the ocean between the North china Block and Siberian Craton was not closed until the Late Guadalupian. The suture of this two blocks is probably extends along the Linxi ophiolite belt, south of the Hegenshan ophiolite belt.

关键词：造山带地质意义内蒙古放射虫二叠纪

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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science china Earth sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, china 2. Graduate University of chinese academy of sciences, beijing 100039, china 3. SHRIMP isotope Laboratory, chinese academy of Geological sciences, beijing 100037, china 4. institute of geology and geophysics, chinese academy of sciences, beijing 10002., china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of chinese academy of sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China institute of geology and geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.

Carbon isotopic variations of Proterozoic carbonates in Jixian, Tianjin, china

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science china Earth sciences 2004年第2期47卷 160-170页

作者： CHU Xuelei, ZHANG Tonggang, ZHANG Qirui, FENG Lianjun & ZHANG Fusong1. institute of geology and geophysics, chinese academy of sciences, beijing 10002., china 2. Key Laboratory for Mineral Resources Research, chinese academy of sciences, beijing 10002., china Correspondence should be addressed to Chu Xuelei (email: xlchu@***) 1. institute of geology and geophysics Chinese Academy of Sciences 100029 Beijing China 2. Key Laboratory for Mineral Resources Research Chinese Academy of Sciences 100029 Beijing China

Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13C values of carbonates are mostly negative in the Changchengian (Changcheng System), varying approximately within a range of (0±1)‰ in the Jixianian (Jixian System), and have commonly positive values of (2±2)‰ in the Qingbaikouan (Qingbaikou System). From Chuanlinggou Formation to Dahongyu Formation, i.e. from ca. 1700 Ma to 1600 Ma, the δ13C values of carbonates increase from about -3‰ to 0‰, but oscillate with large excursion in Dahongyu Formation. Two large excursions occur in the Jixianian, one in Yangzhuang Formation and the other in the third submember of Wumishan Formation overlaying. These integrated and continuous records of carbon isotope reflect secular variations of δ13C value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13C value occurring from the ages of ca. 1700 to ca. 1600 Ma and ＜1300 Ma may signify two correlative global tectonic events.

关键词： Proterozoic, Jixian, carbon isotope, chemostratigraphy, secular variation, global tectonic event.

A Study of the Kunlun-Qilian-Qinling Suture System

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 364-374页

作者： BIAN Qiantao, GAO Shanlin, LI Dihui, YE Zhengren, CHANG Chengfa, LUO Xiaoquan institute of geology and geophysics, chinese academy of sciences, beijing 10002. science Press, chinese academy of sciences, beijing 100717 institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 science Press Chinese Academy of Sciences Beijing 100717 [?]3Bian Qiantao Born in 1945 graduated from the Department of geology South-Central University of Technology in 1970 and obtained his master's degree and doctor's degree at the Graduate School and the Institute of Geology Chinese Academy of Sciences in 1981 and 1987 respectively. He is currently a professor of the Institute of Geology and Geophysics Chinese Academy of Sciences and has long been engaged in the research of tectonics petrology mineral deposits and geochemistry. Tel: (010) 62008058 E-mail: bianqt@***

The Late Neoproterozoic-Early Palaeozoic suture zones within the Central Orogenic Belt of china can be considered a system—the Kunlun-Qilian-Qinling suture system (KQQ suture system). It is basically divided into the western, central and eastern sectors. The western sector consists of the Küda-Subashi suture zone, the Mazar-Kangxiwar suture and the central West Kunlun microblock. The central sector covers the following five suture zones: the Altun, North Qilian, Qaidam northern marginal, Qimantag-Wutuo and East Kunlun southern marginal sutures, in addition to some microblocks such as the mid-south Qilian, Qaidam, Ayakkum and Maqen microblocks. The eastern sector is composed of the Shangdan suture zone, Mianlüe suture zone and central Qinling-Dabie microblock. The KQQ suture system experienced (1) extending-rifting of the Rodinia super-continent in the early-middle Sinian (～780–600 Ma); (2) the formation and evolution of the KQQ archipelagic ocean during the Late Sinian-Ordovician (～600–440 Ma), and (3) closing of the KQQ ocean and forming of the KQQ suture system during the Late Ordovician—early Silurian (～440–400 Ma). As a system comprising many suture zones and microblocks, the KQQ suture system constitutes the foundation of the Central Orogenic Belt of china.

关键词： A Study of the Kunlun-Qilian-Qinling Suture System

Synergetic-bifurcated prediction model of slope occurrence and its application

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science china(Technological sciences) 2003年第z1期46卷 69-77页

作者： HUANG Zhiquan & WANG Sijing North china institute of Water Conservancy and Hydroelectric Power, Zhengzhou 450008, china institute of geology & geophysics, chinese academy of sciences, beijing 10002., china N china Inst Water Conservancy & Hydroelect Power Zhengzhou 450008 Peoples R China chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Landslide prediction is one of the most important aspects of prevention and control for geological hazards and the environmental protection. In order to study the nonlinear methods for landslide prediction, the synergetic-bifurcated model of predicting the timing of slope failure is established by combining Synergetics with Bifurcation Theory based on single-state variable friction law in this paper. The synergetic effects and bifurcated process of the factors in the slope evolution can be characterized in the model. Taking the Xintan Landslide as an example, the prediction of landslide is carried out based on the model suggested.

关键词： friction law, landslide, synergetic-bifurcated model, time prediction.

Discovery of the budding phosphatized globular fossils from the Neoproterozoic Doushantuo Formation at Weng'an, Guizhou Province, china

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Progress in Natural science:Materials International 2006年第10期16卷 1079-1083页

作者： LIU Pengju , YIN Chongyu and TANG Feng (institute of geology, chinese academy of Geological sciences, beijing 100037, china) [a]institute of geology Chinese Academy of Geological Sciences Beijing China

There is much debate on biological affinities of the phosphatized globular fossils from the Neoproterozoic Doushantuo phosphorites at Weng’an, Guizhou Province. Here we report for the first time the budding structures of some of these globular fossils, which have previously been interpreted as the resting eggs and early cleavage embryos of metazoans. The budding structures are similar to the germinating tubes of the spore and zygote of living algae, suggesting that some globular fossils from the Doushantuo phosphorites bear affinity with algae. The present new information indicated various biological affinity of the phosphatized globular fossils from the Doushantuo phosphorites.

关键词： Neoproterozoic Donshantuo Formation globular fossil budding structure algae resting eggs embryos.

Local canonical correlation coefficients and canonical variables of groups of random variables

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chinese science Bulletin 1998年第10期43卷 815-817页

作者： XU Xingzhong institute of Systems science, chinese academy of sciences, beijing 100080, china institute of Systems science Chinese Academy of Sciences Beijing China

The concepts of local correlation coefficient, local canonical correlation coefficients and local canonical variables of groups of random variables are defined, which generalize the classical concepts in two groups of random *** concepts together with total corresponding concepts clarify the correlativity among groups of random variables.

关键词： groups of random variables covariance matrix local canonical correlation coefficients local canonical variables.