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Tectonic Development of the Proterozoic Continental Margins in East Qinling and Adjacent Regions

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Journal of Earth Science 1990年第1期9卷 5-16页

作者： wang hongzhendepartment of geology , china university of geosciences, beijing 100083

The East Qinling and adjacent cratonic regions belong to two geotectonic units, the Sinokorean Subdomain including the Sinokorean Platform and its southern continental margin the North Qinling Belt, and the Yangtzean Subdomain comprising the Yangtze Platform and its northern continental margin the South Qinling Belt .The Qinling region may thus be subdivided into two continental margin belts separated from each other by the Proterozoic Qinling marine realm , which did not disappear until Late Triassic . The convergent crustal consumption zone ,the megasuture between the two belts ,lies between the Fengxian Shangnan line in the north and the Shanyang Xijia line in the south and was much deformed and displaced through Mesozoic intracratonic collision and compression.In the northern subdomain the Lower Proterozoic is represented by protoaulacogen volcano-sediments , the inner Tiedonggou Group and the outer marginal Qinling Group , which were folded and metamorphosed in the Luliangian orogeny ,a general process of aggregation and stabilization of the Early Proterozoic mobile belts between and around the Archaean nuclei. Genuine aulacogen occurred in the Middle Proterozoic and was represented by the Xionger rift volcanics . The Middle and Upper Proterozoic comprise the inner Guandaokou shelf sediments and the outer extensional' back- arc' Kuanping Group behind the Qinling island chain . Oceanic subduction from the south of the Qinling arc representing the Jinningian orogeny caused the folding of the Mid dle and Upper Proterozoic and emplacement of island arc-continent collision type of granite . After the Jinningian orogeny Late Sinian glacigene deposits formed the platform cover and the Erlangping back arc basin began to develop on the northern slope of the Qinling arc .In South Qinling the Lower Proterozoic Tongbe Group was probably an original marginal part of the Yangtze Platform . The passive margin began rifting in Middle Proterozoic with the fo

关键词： Proterozoic East Qinling continental margin .

The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china Earth Sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, wang Chunyong2, TENG Jiwen1, Lü Qingtian3. LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4 1. Institute of geology and Geophysics, Chinese Academy of Sciences, beijing 100029, {3. 2. Institute of Geophysics, {3. Seismological Bureau, beijing 100085, {3. 3. Institute of Deposition Resource, Chinese Academy of geosciences, beijing 10003., {3. 4. School of Exploration and Information, china university of geosciences, beijing 100083. {3. 1. Institute of geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Institute of Geophysics China Seismological Bureau 100085 Beijing China 3. Institute of Deposition Resource Chinese Academy of Geosciences 100037 Beijing China 4. School of Exploration and Information China University of Geosciences 100083 Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3.segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 40 km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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Science china Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, wang Xunlian2, DING Lin1, XIA Guoying3.& wang Lei2 1. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, {3. 2. Faculty of Earth Sciences and Mineral Resources, china university of geosciences, beijing 100083. {3. 3. Tianjin Institute of geology and Mineral Resources, Tianjin 3.0170, {3. 1. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing 100083 China 3. Tianjin Institute of geology and Mineral Resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

Preparation of Barite/TiO_2 Composite Particle and Interaction Mechanism between TiO_2 and Barite Particles

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稀有金属材料与工程 2011年第S3期40卷 193-197页

作者： wang Baikun, Ding Hao, wang Yongkui, Liang Ning china university of geosciences ({3.), {3. 100083. china china Univ Geosci beijing Sch Mat Sci & Technol Beijing 100083 Peoples R China

Barite/TiO2 composite particle (B/TCP) was prepared by coating TiO2 on the surfaces of barite particles through mechano-chemical method. The preparation parameters and pigment properties of B/TCP as well as the interaction mechanism between barite and TiO2 were studied. The results indicated that the mechanical co-grinding process and the proportion of TiO2 affected the properties of B/TCP significantly. B/TCP prepared under optimal conditions was similar to TiO2 in pigment properties. It was mainly the strong electrostatic attraction between barite and TiO2 in water that combined them firmly and then formed B/TCP.

关键词： barite/TiO2 composite particle mechano-chemical titanium dioxide interaction mechanism between particles

Probability parametric imaging with DCE-MRI data to identify prostate cancer in the peripheral zone

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Progress in Natural Science:Materials International 2006年第9期16卷 948-953页

作者： HUANG Xinrui, wang Qiang, XU Yufeng, wang Xiaoying and BAO Shanglian ( The Key Laboratory of Medical Physics and Engineering, Peking university, {3. 100871, china The Medical School of Peking university, {3. 100083. china 3. The First Hospital of Peking university, {3. 10003., china) [a]The key Laboratory of Medical Physics and Engineering Peking University Beijing China [b]The Medical School of Peking university Beijing China [c]The First Hospital of Peking university Beijing China

To quantitatively analyze prostate dynamic contrast-enhanced magnetic resonance images (DCE-MRI), a retrospective study was carried out to construct a mathematical model to predict whether a lesion is cancerous or not. With known diagnosis of 52 re-gions-of-interest (10 malignant, 26 benign and 16 normal) in peripheral zone (PZ) of prostate from 18 patients undergoing needle biopsy and 8 normal volunteers, we combined feature parameters (k1, k2 and tp) from the linear-slope model with logistic regression to determine the statistical probability model. Prostate cancerous probability maps were derived using the model on each subject to examine the correlation between the model-based prediction and the known diagnosis. Compared the model prediction results of 52 regions-of-interest with the histopathologic results, the total agreement rate was 90.4 % ; the agreement rate was 60 % for the malignant and 97. 6 % for the nonmalignant. The diagnostic results only referencing the probability maps by two radiologists showed a high agreement in tissue characteristics and lesion location with the combining results from other diagnostic techniques such as PSA (prostate specific antigen) level and MRS (magnetic resonance spectroscopy) .

关键词： time-intensity curve prostate DCE-MRI logistic regression probability parametric image.

Correlation of Upper Devonian and Lower Carboniferous Depositional Sequences in Different Facies Belts on Southern Margin of Upper Yangtze Platform

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Journal of Earth Science 1999年第2期18卷 38-46页

作者： wang Xunlian Department of geology and Mineral Resources, china university of geosciences, {3. 100083

A fundamental problem in sequence stratigraphy is whether the sequences are global in extent and whether the sea level changes are eustatic in nature. Study on the Upper Devonian and Lower Carboniferous depositional sequences in different facies belts on the southern margin of the Upper Yangtze platform shows that different orders of sequences possess distinctive distribution and correlation in space, although the sea level changes in various orders of sequences may be primarily global in nature. The present paper regards the distribution in space, especially in different facies belts, as a criterion for defining and recognizing the various orders of sequences. The orthosequence (third order sequence) is probably global in nature, which may be discerned in various depositional facies belts on the continental margin and can be correlated over long distances, sometimes maybe worldwide. Commonly, correlation of the subsequences (fourth order sequences with time interval of 0.5 Ma to 1.5 Ma) is difficult in different facies belts, although some of them are probably also worldwide in distribution. A subsequence should be distinguishable and correlatable within at least one facies belt. The higher order sequences, including parasequences (fifth order sequences) and microsequences (sixth order sequences), are regional or local in distribution. They may have reflected the longer and shorter Milankovitch cycles respectively. Orthosequences and subsequences are usually recognizable in different facies belts, while parasequences and microsequences may be distinguished only in shallow marine deposits, but not in slope and basin facies deposits.

关键词： facies belt orthosequence subsequence parasequence microsequence meter scale cyclothem Milankovitch cycle.

A New SHRIMP Age of the Xiamaling Formation in the North china Plate and Its Geological Significance

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 1103-1109页

作者： GAO Linzhi~(1,*)ZHANG Chuanheng~2 SHI Xiaoying~2 ZHOU Hongrui~2 wang Ziqiang~2 SONG Biao~(1,3. 1 Institute of geology,Chinese Academy of Geological Sciences,beijing 10003.,{3. 2 china university of geosciences(beijing),beijing 100083.{3. 3.beijing SHRIMP Central,10003. beijing,{3. Institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

Setting up the hypostratotype of late Precambrian is the main aim of the research on the Meso-and Neoproterozoic in North *** chronostratigraphic position is the key in this study. However,many key horizons have not been calibrated with the high-quality isotopic *** the reported new U-Pb age with the Sensitive High-Resolution Ion Microprobe（SHRIMPⅡ）,a zircon U- Pb age was obtained of the ash bed in the Xiamaling Formation in North china Plate,yielding a weighted mean;Pb/;U age of 13.8±12 *** is the first SHRIMP U-Pb age from the Xiamaling Formation in the North china Plate,and represents the depositing time of the middle part of the Xiamaling *** zircon age plays an important role to understanding geological evolution of the North china Plate during Meso-and Neoproterozoic.

关键词： SHRIMP U-Pb Dating Mesoproterozoic Xiamaling Formation North china Plate

Experimental remolding on the caprock's 3. strain field of the Indosinian-Yanshanian epoch in Tongling deposit concentrating area

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Science china Earth Sciences 2005年第7期48卷 863-874页

作者： DENG Jun1,HUANG Dinghua2,wang Qingfei1,WAN Li1,SUN Zhongshi3.YANG Liqiang1 & GAO Bangfei1 1. State Key Laboratory of Geological Processes and Mineral Resources,china university of {3.,beijing 100083.china 2. Faculty of Earth Sciences,china university of {3.,Wuhan 43.074,china 3. Department of Earth Sciences,Jilin university,Changchun 13.061,china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Department of Earth Sciences Jilin University Changchun 130061 China

Based on field observations and rheology analysis, we perform one analogue experiment and remold the 3. structural frame of Tongling deposit concentrating area firstly. Then we disassemble and dialyze the 3. structures of the model using the methods of "slicing" and "stripping". A series of sliced planes vertical to the fold hinges show similar landscapes of that in the drill hole profiles. Meanwhile, layer stripping analysis indicates that the deformation features of each layer in the model are qualitatively analogical to those obtained from field observations. Through contrasting the 3. structure between the experimental model and the field phenomena, we verify the following 3. deformation features of the caprock in this area: (1) the Tongling area mainly consists of three series of NE S-typed fold groups; (2) in the uniform stress field, the incoherent folds universally develop in different positions, along different axes as well as in different strata; (3. the faults propagate upward which are mostly inter-bedded detachment faults, while the fold amplitudes decrease while going deeper; and (4) the folds and cleavages are highly developed in the Silurian System indicating that the deformation effect of the Indosin-ian-Yanshanian structural layer terminates at this layer, which suggests that the Silurian System is the crucial layer for the inversion between brittle and plastic deformation domains and the underlying strata are subject to the control of another deformation system with distinct properties.

关键词： Tongling deposit concentrating area Indosinian-Yanshanian epoch 3. structural frame of the caprock analogue experiment slicing and stripping analysis structural model.

Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern china

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Science china Earth Sciences 2006年第3期49卷 295-303页

作者： wang Hongqiang1,2, DENG Chenglong1, ZHU Rixiang1 & XIE Fei3.1. Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of geology and Geophysics, Chinese Academy of Sci- ences, beijing 100029, {3. 2. School of the Earth Sciences and Resources, china university of geosciences, beijing 100083. {3. 3. Hebei Province Institute of Cultural Relics, Shijiazhuang 050000, {3. 1. Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. School of the Earth Sciences and Resources China University of Geosciences Beijing 100083 China 3. Hebei Province Institute of Cultural Relics Shijiazhuang 050000 China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern china, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1 Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3.and 1.1 Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.