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TIME-IGGCAS model validation:Comparisons with empirical models and observations

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Science China Technological sciences 2008年第3期51卷 308-322页

作者： YUE XinAn1,2,3, WAN WeiXing1, LIU LiBo1, NING BaiQi1, ZHAO BiQiang1 & ZHANG ManLian1 1 Institute of geology and geophysics, chinese academy of sciences, beijing 10002., China 2 Wuhan Institute of Physics and Mathematics, chinese academy of sciences, Wuhan 430071, China 3 Graduate University, chinese academy of sciences, beijing 100049, China 1. Institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China 2. Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China 3. chinese academy of sciences Graduate University Beijing 100049 China

The TIME-IGGCAS (Theoretical Ionospheric Model of the Earth in Institute of Ge- ology and geophysics, chinese academy of sciences) has been developed re- cently on the basis of previous works. To test its validity, we have made compari- sons of model results with other typical empirical ionospheric models (IRI, NeQuick-ITUR, and TItheridge temperature models) and multi-observations (GPS, Ionosondes, Topex, DMSP, FORMOSAT, and CHAMP) in this paper. Several conclu- sions are obtained from our comparisons. The modeled electron density and elec- tron and ion temperatures are quantitatively in good agreement with those of em- pirical models and observations. TIME-IGGCAS can model the electron density variations versus several factors such as local time, latitude, and season very well and can reproduce most anomalistic features of ionosphere including equatorial anomaly, winter anomaly, and semiannual anomaly. These results imply a good base for the development of ionospheric data assimilation model in the future. TIME-IGGCAS underestimates electron temperature and overestimates ion tem- perature in comparison with either empirical models or observations. The model results have relatively large deviations near sunrise time and sunset time and at the low altitudes. These results give us a reference to improve the model and enhance its performance in the future.

关键词： ionosphere theoretical model empirical model satellite observation relative deviation

Digital image analysis of palaeoenvironmental records and applications

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chinese Science Bulletin 2002年第23期47卷 1957-1963,2025-2026页

作者： SUN Donghuai1,2, LIU Yu2 & TAN Ming31. South China Sea Institute of Oceanology, chinese academy of sciences. Guangzhou 5.0301, China 2. State Key Laboratory of Loess and Quaternary geology, Earth Environmental Institute, chinese academy of sciences, Xi’an 710075. China 3. Institute of geology and geophysics, chinese academy of sciences, beijing 10002., China South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China State Key Laboratory of Loess and Quaternary geology Earth Environmental Institute Chinese Academy of Sciences Xi’an China Institute of geology and geophysics Chinese Academy of Sciences Beijing China

Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

关键词： digital image environmental records.

Age Assignment of the Lycoptera- bearing Bed

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Acta Geologica Sinica(English Edition) 1994年第3期68卷 329-347页

作者： Li Peixian, Su Deying, Li Yougui and Yu JingxianInstitute of geology, chinese academy of Geological sciences, beijing chinese academy of Geological sciences Beijing

In the Yanliao area, the occurrence of the Nestoria-Keratestheria fauna and the Eoparacypris- Luanpingella-Darwinula assemblage in the Dabeigou Formation s.s., a Rb-Sr isochron age of 145.2 Ma for the Baiqi Formation and a complete stratigraphic sequence-all this proves that the Lycoptera-bearing bed overlies the Upper Jurassic. The Jehol fauna comprises the primitive Trigonioidids fauna, Eosestheria fauna, Lycoptera fauna et al., and their own laws of evolution expound that they belong to Cretaceous faunas. The associations of Eosestheria with Yanjiestheria, Lycoptera with Eosestheria, and Kuntulunia with Yanjiestheria as well as the occurrence of early angiosperms and sporo - pollen in the Fuxin Formation and its equivalents also demonstrate that the Lycoptera-bearing, bed should be assigned to the Cretaceous. The confirmation of the existence of Aucellina in the Jixi Group and the correlation of Trigonioidids and Cypridids with those in the equivalent strata of Japan and Western Europe have also been verified by corresponding marine strata. According to the magnetostratigraphic data from Zhejiang and Songliao, it has been preliminarily ascertained that M0 between the mixed polarity zone in the lower part and the normal polarity zone in the middle part of the Cretaceous is located in the upper member of the Huangjian Formation of the Jiande Group and the top member of the Denglouku Formation of the same group, and the isotopic age data of the Jehol and Jiande Groups show that the approximate geologic age of the Lycoptera bed is 135.122 Ma. These prove that the Lycoptera bed should be assigned to the Cretaceous.

关键词： Cretaceous Jurassic-Cretaceous boundary Lycoptera- bearing bed Jehol fauna

Vermiform trace fossils from the Precambrian Ruyang Group, western Henan

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chinese Science Bulletin 1997年第3期42卷 251-254页

作者： HU Jianmin, MENG Qingren and LI Wenhou1 Xi’ an College of geology, Xi’an 71005., China 2. Institute of geophysics, chinese academy of sciences, beijing 100101, China 3 Department of geology, Northwest University, Xi’an 710069, China Xi’an College of geology Xi’an China Institute of geophysics Chinese Academy of Sciences Beijing China Department of geology Northwest University Xi’an China

THE origin and evolution of Precambrian lives has been a long-standing controversial problem. It is now generally accepted by most paleontologists that the origin of metazoa can be traced back to more than 1000 Ma, because the Ediacara and latest pre-Ediacara fauna, such as the Huainan fauna, are featured by their diversification of forms, complicated structures

关键词： Precambrian trace fossil Ruyang Group.

Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese Science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3,LIU XiaoDong 4 & TIAN ZhiPing 2,5.1 Climate Change Research Center,chinese academy of sciences,beijing 10002.,China 2 Nansen-Zhu International Research Centre,Institute of Atmospheric Physics,chinese academy of sciences,beijing 10002.,China 3 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,chinese academy of sciences,beijing 10002.,China 4 State Key Laboratory of Loess and Quaternary {15.,Institute of Earth Environment,chinese academy of sciences,Xi’an 710075.China 5.Graduate University of chinese academy of sciences,beijing 100049,China 1. Climate Change Research Center Chinese Academy of Sciences Beijing 100029 China 2. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China 4. State Key Laboratory of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. Graduate University of chinese academy of sciences Beijing 100049 China

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National Center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science China Earth sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2, WANG Pinxian1, CHENG Xinrong1, WANG Rujian1 & SUN Xiangjun1,3 1. State Key Laboratory of Marine geology, Tongji University, Shanghai 200092, China 2. Institute of geology and geophysics, chinese academy of sciences, beijing 10002., China 3. Institute of Botany, chinese academy of sciences, beijing 100093, China State Key Laboratory of Marine geology Tongji University Shanghai China Institute of geology and geophysics chinese academy of sciences beijing China Institute of Botany chinese academy of sciences beijing China

The deep sea records from the ODP Sites 1143 and 1144 in the northern and southern South China Sea (SCS), including foraminiferal δ 18O and δ 13C, Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 41 ka and 23 ka cycles. Although G. ruber δ 13C of Site 1143 is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South China Sea.

关键词： South China Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

Palynological record during the Pleistocene (between 1.05.Ma and 0.36 Ma) from ODP1144, northern South China Sea

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Science China Earth sciences 2004年第1期47卷 30-36页

作者： HUANG Fei & SUN XiangjunInstitute of geology and Paleontology, chinese academy of sciences, Nanjing 210008, China Institute of Botany, chinese academy of sciences, beijing 100093, China Key Laboratory of Marine geology, Ministry of Education, Tongji University, Shanghai 200092, China Correspondence should be addressed to Huang Fei 1. Institute of geology and Paleontology Chinese Academy of Sciences 210008 Nanjing China 2. Institute of Botany Chinese Academy of Sciences 100093 Beijing China 3. Key Laboratory of Marine geology Ministry of Education Tongji University 200092 Shanghai China

This paper presents the pollen record from the lower section of ODP1144 (depth 5.1.3-225.7 m, ca. 1.05.0.36 Ma). Two pollen zones (PA and PB) and eleven pollen subzones are recognized. Within zone PB, the 11 pollen subzones (PB21-11) are defined according to the pine, fern and herb variations, and are equivalent to the marine isotope stages 21-11 (MISs 21-11). The interglacial periods are typified by an increase in pine pollen and fern spores, and a decrease in herbaceous pollen, while the patterning during the glacial periods is just the opposite. During the interglacial periods, pollen assemblages were dominated by pine similar to those of the present day, suggesting that the paleoenvironment of the interglacial periods was similar to that of the present day, whereas the glacial periods are marked by an increase in herbaceous pollen, mainly Gramineae and Cyperaceae, indicating that grassland covered the exposed continental shelf when sea level declined. Increased Artemisia percentages and the highest pine influx during MIS12 may result from a stronger winter monsoon.

关键词： pollen record, Pleistocene, ODP1144, northern South China Sea.

Interactions between hotspots and the Southwest Indian Ridge during the last 90 Ma:Implications on the formation of oceanic plateaus and intra-plate seamounts

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Science China Earth sciences 2011年第8期54卷 1177-1188页

作者： ZHANG Tao 1,2,3,4,LIN Jian 5.& GAO JinYao 3,4 1 Institute of Geodesy and geophysics,chinese academy of sciences,Wuhan 430077,China 2 Graduate University of chinese academy of sciences,{5. 100049,China 3 The Second Institute of Oceanography,State Oceanic Administrator,Hangzhou 310012,China 4 Key Laboratory of Submarine Geosciences,State Oceanic Administrator,Hangzhou 310012,China 5.Department of geology and geophysics,Woods Hole Oceanographic Institution,Woods Hole,MA 025.3,USA 1. Institute of Geodesy and geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. The Second Institute of Oceanography State Oceanic Administrator Hangzhou 310012 China4. Key Laboratory of Submarine Geosciences State Oceanic Administrator Hangzhou 310012 China

This study investigates the relationship between the hotspot-ridge interaction and the formation of oceanic plateaus and seamounts in the Southwest Indian *** first calculated the relative distance between the Southwest Indian Ridge (SWIR) and relevant hotspots on the basis of models of plate reconstruction,and then calculated the corresponding excess magmatic anomalies of the hotspots on the basis of residual bathymetry and Airy *** results reveal that the activities of the Marion hotspot can be divided into three main phases:interaction with the paleo-Rodrigues triple junction (73.6-68.5.Ma),interaction with the SWIR (68.5.42.7 Ma),and intra-plate volcanism (42.7-0 Ma).These three phases correspond to the formation of the eastern,central,and western parts of the Del Cano Rise,*** magnitude and apparent periodicity of the magmatic volume flux of the Marion hotspot appear to be dominated by the hotspot-ridge *** periodicity of the Marion hotspot is about 25.Ma,which is much longer than that of the Hawaii and Iceland hotspots (about 15.Ma).

关键词： Southwest Indian Ocean hotspot-ridge interaction magmatic volume flux oceanic plateaus seamounts

CARBONATITES FROM THE EASTERN HIMALAYAN SYNTAXIS: PETROLOGY AND TECTONIC IMPLICATIONS

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地学前缘 2000年第S1期7卷 10-11页

作者： Liu Yan 1, Zhong Dalai 2, Ji Jianqing 3(1 Institute of geology, chinese academy of Geological sciences, beijing 100037, China 2 Institute of geology & geophysics, chinese academy of sciences, beijing 10002., China 3 Department of geology, Pek

Most carbonatites occur in relatively stable, intra\|plate areas but some are found to occur in near to plate margins and may be linked with plate separation (Woolley, 1989). Although many carbonatites have been discovered to occur in the orogenic belts in recent years, most of these rocks are related to post\|orogenic magmatism, that is, the rocks occur in the specially extensional setting. Therefore it is unusual that such magmatic rocks occur in the typical convergent environment. Here we report carbonatites and associated ultramafic and mafic rocks in the core of the eastern Himalayan syntaxis. The eastern Himalayan syntaxis consists of three tectonic units: the Gangdise, the Yarlung Zangbo, and the Himalayan units, each of which is bounded by faults (Liu & Zhong, 1997). The Himalayan unit, the northernmost exposed part of the Indian plate, is divided into two complexes, the amphibolite facies complex in the south and the granulite facies complex in the north. The granulite facies complex in the Himalayan unit have been argued to experience high\|pressure metamorphism and represent materials buried to upper\|mantle depths (Liu & Zhong, 1997). The carbonatites and associated ultramafic and mafic rocks only occur in the granulite facies rocks and are divided into two belts: northern and southern *** northern belt extends at least 30km, and is about 20km in width. The southern belt extends several kilometers, and is 3km or so in width. Each belt consists mainly of differently compositional dykes, extending parallel to gneissosity of granulite facies gneiss. Carbonatitic agglomerates are observed in the northern belt. From the center of carbonatite dykes to country rocks, five types of rock are observed: the center parts of carbonatites, the rim parts of carbonatites, ultramafic and mafic rocks, altered rocks and country rocks. The gneissosity of country rock was deformed by intrusion of dykes.

关键词： Eastern Himalayan Syntaxis carbonatites ultramafic rocks carbonatitie magmatism convergent environment