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Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14.million years ago

Science China earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2. LI Zhen4. TAN Hongbing2.& WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, Institute of earth Environment, Chinese Academy of {2., Xi’an 710075 China 2. Qinghai Institute of Salt Lakes, Chinese Academy of {2.. Xining 810008, China 3. Institute of Geology and Geophysics, Chinese Academy of {2., Beijing 10002., China 4. Department of Geography, Qinghai Normal {4., Xining 810008, China Chinese Acad Sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China Chinese Acad Sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Qinghai Normal Univ Dept Geog Xining 810008 Peoples R China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14.million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4.00 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2. T1 were formed at 14. 11.3, 1.55, 1.2. 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14.million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14. 11.3, 1.2.and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12.million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 4.2.m during the past 1.2.million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

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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. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002., China 3. College of Environmental sciences, MOE Laboratory for earth Surface Processes, Peking university, Beijing 100871, China 4. Institute of Botany, Chinese Academy of sciences, Beijing 100093, China 5. Northwest Sci-Tech university of Agriculture and Forestry, Yangling 712.00, China 6. Network Center, China Agricultural university, Beijing 100094. China 1. Department of Plant Nutrition China Agricultural University Beijing 100094 China 2. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. College of Environmental sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China 4. Institute of Botany Chinese Academy of Sciences Beijing 100093 China 5. Northwest Sci-Tech university of Agriculture and Forestry Yangling 712100 China 6. Network Center China Agricultural University Beijing 100094 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.

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Synthesis and photochromic properties of WO_3 powder induced by oxalic acid

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Science China Chemistry 2009年第5期52卷 609-614页

作者： SHEN Yi1, ZHU Hua1, HUANG Rong1, ZHAO Li2.& YAN ShaNing1 1 faculty of Material Science and Chemical Engineering, China university of {2., wuhan {4. China 2.faculty of Materials Science and Engineering, Hubei university, wuhan 4.0062. China 1. faculty of Material Science and Chemical Engineering China University of Geosciences Wuhan 430074 China 2. faculty of Materials Science and Engineering Hubei University Wuhan 430062 China

Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3, made up of regularly spindle particles with 2.0-300 nm in length and 30-50 nm in width. The ratio of the length and width was from 4.to 10. Moreover, the special morphology improved its absorptive capacity to the excitation light source, resulting in its high photochromic properties.

关键词： WO3 powder photochromism oxalic acid organic inducer

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Paleotemperature changes over the past 3000 years in eastern Beijing, China: A reconstraction based on Mg/Sr records in a stalagmite

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Chinese Science Bulletin 2003年第4期48卷 395-400页

作者： MA Zhibang1, LI Hongchun2. XIA Ming1, KU Tehlung2. PENG Zicheng3, CHEN Yushu4.& ZHANG Zhaofeng3 1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002., China 2. Department of {2. sciences, university of Southern California, Los Angeles, CA90089-074., USA 3. Department of {2. and Space Science, university of Science and Technology of China, Hefei 2.002., China 4. Beijing Foshan Tourist Service Centre, Beijing 1012.1, China Institute of Geology and Geophysics. Chinese Academy of sciences Beijing 100029 China

The Mg/Sr ratio in a stalagmite, which is di-rectly proportional to DMg/Ca, the solid-liquid distribution coefficient of Mg, is proposed as a geochemical thermometer to estimate paleotemperature changes. The paleotempera-ture change in eastern Beijing over the past 3000 years has been reconstructed by using this thermometer in the stalag-mite ZFFS-1 from Jingdong Cave. The records can be di-vided into two periods: 3000—2.00 aBP, cool and wet, the air temperature averaging 9.8℃; and 2.00 aBP—present, hot and dry, the air temperature being 1℃ higher than the mean value (11.7℃) of the past 3000 years. During 500—2.0 aBP, the air temperature was about 1.2. lower than that of the present, corresponding to the Little Ice Age in Europe. Like d 18O and d 13C, Mg/Sr (or DMg/Ca) reflects an obviously warming trend of the past 2.0 years. These results are sup-ported by historic records.

关键词：北京京东溶洞石笋 Mg/Sr记录古气温测年 3000年

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Fluorescence response of hypocrellin B to the environmental changes in a mimic biological membrane——liposome

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Science China Chemistry 2004年第4期47卷 335-339页

作者： JIN Xuanye1,2. ZHAO Yuewei1, XIE Jie1 & ZHAO Jingquan1 1. CAS Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Science, Beijing 100080, China 2. School of earth sciences and Resources, China {2. of geosciences, Beijing 100083, China 1. CAS Key Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Science 100080 Beijing China 2. School of earth sciences and Resources China University of Geosciences 100083 Beijing China

Liposome is well known as not only a drug-delivery system but also a simple model for biological membranes. It was reported that fluorescence properties of hypocrellins were changeable over some extreme pH values. In the current work, the effects of the microenvironments on the fluorescence properties of HB in liposome, including approximately physiological range of pH values pH = 6.0-8.0, concentration of cholesterols and ionic strength of the solution, were studied. It was found that the fluorescence intensity of HB was sensitive to and also regulated by the microenvironments. When concentration of cholesterols and ionic strength keep invariable in PBS solution, there exists the maximum for the fluorescence of HB-liposome at pH 7.4.while the minimum for that of HB at pH 7.0. In addition, when pH value keeps constant (7.2., there exists the maximum at the ionic strength of 0.12.mol/kg while that at the concentration of 6×10?4.mol/L for cholesterols. On the other hand, in PBS solution, the lower the ionic strength is, the higher the fluorescence intensity is. The environment-sensitive fluorescence may be potentially applicable to probe some specific environmental features in cells or tissues.

关键词： microenvironment hypocrellin B liposome fluorescence

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Phytolith Records in Vermicular Red earth:Implications for Bioclimatic Variationsduring Pleistocene

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Journal of China university of geosciences 2001年第1期12卷 27-30页

作者： Gu Yansheng Zhuo Ying Zhang Zejun faculty of earth {2., China university of {4., wuhan 4.0074 faculty of earth {2. China University of Geosciences

Phytolith analysis is employed in bioclimatic research into vermicular red earth, especially into its form, assemblage and zonation. The phytolith assemblage is divided into 10 zones. The statistics and main factor analysis of phytolith show that the obtained main factor load curves could suggest a climate change. Combined with phytolith assemblage feature, the bioclimatic variation of vermicular red earth during its formation stage, consisting of 5 arid-cold stages, {2.warm-humid stages and 2.mild stages, is reconstructed in detail. The research results indicate that phytolith records are ideal paleoclimatic signals in vermicular red earth, and that abundant information on environmental evolution can be located.

关键词： phytolith records vermicular red earth bioclimatic variation.

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Delineation of Potential Mineral Resources RegionBased on Geo-anomaly Unit

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Journal of earth Science 2000年第2期19卷 66-71页

作者： Chen Yongqing faculty of earth Resources, China {2. of geosciences, {4. 4.0074.The Center for Development and Research, China Geological Survey, Beijing 100083 Liu Hongguang faculty of earth Resources, China {2. of geosciences, {4. 4

The geological anomaly unit method (GAUM) is a new way to delineate and evaluate ore finding targets in line with the “geological anomaly ore finding theory”. Comprehensive ore finding information from geological, geochemical and geophysical data is used for quantitative measurement of the “ore forming geological anomaly unit” in this paper. The main procedures are shown as follows: (1) The geo anomalous events associated with gold mineralization are analyzed in Tongshi gold field; (2. The zonation in the concentrated heavy minerals and the stream sediment elements of ore forming geo anomaly are studied in detail; (3) The deep geological structural framework is deduced by means of the synthetic geological interpretation of gravity and magnetic information; (4. The ore controlling geo anomalies and ore anomalies are chosen as the variables of the favorable ore forming indexes that can be used for the quantitative delineation and evaluation of the potential ore forming regions.

关键词： ore forming geo anomaly unit mineral resources areas comprehensive ore forming information favorable ore forming index Tongshi gold field western Shandong Province Eastern China.

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Extensional Tectonic Framework of Post High and Ultrahigh Pressure Metamorphism in Dabieshan,China

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Journal of earth Science 1998年第1期17卷 3-7页

作者： Zhong Zengqiu Suo Shutian You Zhendong faculty of earth {2., China university of {4., wuhan 4.0074

The most prominent feature of the extensional tectonic framework of post high pressure (HP) and ultrahigh pressure (UHP) metamorphism in Dabieshan is the development of the multi layered extension detachment zones surrounding the core of the Luotian dome, and the separation of the UHP, HP and epidote blueschist units by the detachment zones, which form the vertically stacking sheet like slices of the HP and UHP metamorphic rocks. From the core outwards, exist the HP and UHP rock barren Dabie complex, UHP unit, HP unit and epidote blueschist unit. The extension tectonics of post HP and UHP metamorphic event constrain the distribution and present configuration of the HP and UHP metamorphic rocks, and the extensional tectonic framework bears some similarities to the Cordillera metamorphic core complex. It is suggested that partial melting happened in the Dabie gneiss complex (DGC) and UHP unit contemporaneously with the extrusion of UHP metamorphic rocks into the lower-middle crust. The formation and emplacement of the migmatite and granites are the response to the change in thermal state, facilitating the transfer from the compressive regime to extensional regime in the crust. The large scale crustal extension and uplift and the accompanying anatexis in Dabieshan are probably related to the delamination and magmatic underplating in the mantle and the lower crust.

关键词： high and ultrahigh pressure metamorphic rocks post collision extension tectonics Dabieshan.

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Paleoenvironmental records from the northern South China Sea since the Last Glacial Maximum

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Acta Oceanologica Sinica 2010年第3期29卷 46-62页

作者： GE Qian CHU Fengyou XUE Zuo LIU J Paul DU Yuansheng FANG Yinxia faculty of earth {2. China University of Geosciences Wuhan 430074 China Key Laboratory of Submarine geosciences State Ocean Administration Hangzhou 310012 China Department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh NC 27695 USA

Core ZHS-176 contains the paleoenvironmental records from the northern South China Sea （NSCS） since the Last Glacial Maximum （LGM）. A coupled approach based on clay mineral assemblages, planktonic foraminiferal oxygen and carbon isotopes, and calcium carbonate content is used to trace the sources of the fine-grained sediment and to investigate the paleoenviornmental evolution in this area. Clay mineral assemblages are dominated by illite （average about 39%） and chlorite （about 2.%）, which comes mainly from Taiwan and the East China Sea. Kaolinite, which accounts for about 13%, comes mainly from the Zhujiang （Pearl） River, and Luzon Island is the main source for smectite （about 2.%）. The planktonic foraminiferal oxygen isotopic oscillations during the last glacial period are coeval with climate variations recorded in the Greenland ice core and Western Pacific sediment. These variations include the LGM, Heinrich event 1, Bφlling-Allerφd （B/A）, and Younger Dryas. For the Holocene, three periods of strong precipitation （S1-S3） and three periods of weak precipitation （W1-W3） are identified. The oxygen isotopic record exhibits corre-lation with climate records from distant regions, including the high-latitude Northern Hemisphere, providing evidence for global tele-connection among regional climate. A brief, negative planktonic foraminiferal carbon isotopic excursion during B/A reflects increased methane released from marine gas hydrate due to the rapid warming of the water. By comparing calcium carbonate content curves of the core ZHS-176 with these of other five boreholes lying above the lysocline, a remarkable low calcium carbonate event is found during the early Holocene in NSCS.

关键词： clay mineral oxygen and carbon isotopes calcium carbonate content South China Sea paleoenvironmental evolution

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Devonian Sequence Stratigraphy and Sea Level Change Cycles in South China

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Journal of earth Science 1996年第1期15卷 72-79页

作者： Du Yuansheng Gong Yiming (faculty of earth {2., China university of {4., wuhan 4.0074. Wu Yi (Guangxi Institute of Geology, Nanning 53002.) Liu Benpei Feng Qinglai (faculty of earth {2., China university of {4., wuhan 4.0074.

The Devonian is well developed in South China and has drawn a great attention from the geologists both at domestic and abroad. On the basis of study on the sequence stratigraphy in more than 10 sections in Guizhou, Guangxi, Longmenshan and Southern Qinling within South China we have identified 2. sequences and T-R cycles that correspond to third-order sea level changes. These sea level change cycles were controlled by autorhythm(Pragian,Eifelian), allorhythm(Lochkovian,Emsian,Givetian) and coupling rhythm mechanisms (frasian, Famennian and F-F boundary).

关键词： south China Devonian,sequence,sea level change cycle.

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