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Seismogenic Structure of the 1605 Qiongshan M7½ Earthquake and Its Holocene Activity History in Northern Hainan Island, china: Evidence from Cross-Section Drilling and Shallow Seismic Profile

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Journal of Earth Science 2024年第3期35卷 905-917页

作者： Chaoqun wang Liyun Jia Daogong {2. Shibiao Bai Zhengwang {2. Dongxia Sun Xiaoxiao Yang lei Zhang Xiumin Ma institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesBeijing 100081China Key Laboratory of Geohazard Prevention of Hilly Mountains Ministry of Land and Resources(Fujian Key Laboratory of Geohazard Prevention)Fuzhou 350002China Observation and Research Station of Crustal Stress and Strain in Beijing Ministry of Natural ResourcesBeijing 100081China College of Marine Science and Engineering Nanjing Normal UniversityNanjing 210023China hubei Subsurface Multi-Scale Imaging Key Laboratory School of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China

The 1605 M7½ Earthquake is the only earthquake in the history of china that has caused large-scale land subsidence into the sea,with the total area of land subsidence exceeding 100 *** disaster has led to the sinking of 72.*** is still no clear understanding of the source seismogenic fault of this *** this work,we conducted a detailed study of the middle segment of the Maniao-Puqian fault(MPF),which is the epicenter area,through geomorphological survey,data collection,shallow seismic exploration,cross-section drilling,and chronological *** results showed that the middle segment of the MPF zone is composed of three nearly parallel normal faults with a dextral strike-slip:“Macun-Luodou fault(F2.1),Haixiu-Dongyuan fault(F2.2.,and ChangliuZ{2.xihe fault(F2.3)”.And F2.2.is composed of two secondary faults,namely F2.2.and F2.2.,with a flower-shaped structure buried under the *** is distributed nearly east-west,dipping to the north and has experienced at least five stages of activities since the *** vertical activity rates of F2.2.and F2.2.are~2.32.and~2.5 mm/a,since the Holocene,*** were eight cycles of transgression and regression since the *** fault activity resulted in the thickening of the Holocene strata with a slight dip to the south,on the hanging wall,showing V-shaped *** MPF is likely the source seismogenic fault of the M7½ earthquake that hit Qiongshan in 1605.

关键词： seismogenic structure earthquakes Maniao-Puqian fault fault activity history geomorphology.

Improved retracking algorithm for oceanic altimeter waveforms

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Progress in Natural Science:Materials International 2009年第2期19卷 195-203页

作者： Lifeng Bao,Yang Lu,Yong wang institute of {2. and geophysics,Chinese Academy of Sciences,wuhan 430077,china [a]institute of geodesy and {2. Chinese Academy of Sciences Wuhan 430077 China

Over the deep oceans without land/ice interference,the waveforms created by the return altimeter pulse generally follow the ocean model of Brown,and the corresponding range can be properly determined using the result from an onboard tracker. In the case of com-plex altimeter waveforms corrupted due to a variety of reasons,the processor on the satellite cannot properly determine the center of the leading edge,and range observations can be in error. As an efficacious method to improve the precision of those altimeter observations with complex waveforms,waveform retracking is required to reprocess the original returning pulse. Based on basic altimeter theory and the geometric feature of altimeter waveforms,we developed a new altimeter waveform retracker,which is valid for all altimeter wave-forms once there exists a reasonable returning signal. The performances of the existing Beta-5 retracker,threshold retracker,improved threshold retracker,and the new retracker are assessed in the experimental regions (china Seas and its adjacent regions),and the improvements in the accuracy of sea surface height are investigated by the difference between retracked altimeter observations and ref-erenced geoid. The comparisons denote that the new algorithm gives the best performance in both the open ocean and coastal regions. Also,the new retracker presents a uniform performance in the whole test region. Besides,there is a significant improvement in the short-wavelength precision and the spatial resolution of sea surface height after retracking process.

关键词： Altimetry Waveform retracking Sea surface height

APPLICATION OF ANALYTIC HIERARCHY PROCESS TO ASSESSING THE ECOLOGICAL VULNERABILITY OF WETLANDS IN THE JIANGHAN PLAIN

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Chinese Geographical Science 2003年第3期13卷 272-276页

作者： wang xue-{2., NING Long-mei, hu wang-bin({2. of geodesy and geophysics, Chinese Academy of Sciences, wuhan 430077, P. R. china) institute of geodesy and {2. Chinese Academy of Sciences Wuhan P. R. China

Wetlands in the Jianghan Plain are important components of wetland types in lake area in the middle and lower reaches the Changjiang (Yangtze) River and they fulfill many uses and functions related to hydrology, waste assimilation, ecosystem productivity and biodiversity. Owing to natural factors and human activities, especially excessive reclamation from lakes, the shrinking process of the lakes has been accelerated. Wetland ecosystem has shown the characteristics of vulnerability. According to the analysis of wetland ecological function in the Jianghan Plain, this paper presented an index system related to productivity, stability and environmental capacity. By using the method of Analytic Hierarchy Process, we computed the values of the relative weights of the indexes, and evaluated the vulnerability level of the wetland ecosystem by the method of multi-indexes. The case study showed that the fragile extent of wetland ecosystem in the Jianghan Plain is 5.6. This means that the wetland ecosystem in the Jianghan Plain is laid to the state of middle vulnerability. Therefore, the wetland conservation and eco-rehabilitation in the Jianghan Plain should be paid attention to.

关键词： wetland ecological vulnerability AHP the jianghan plain

THE SIMULATED STORAGE CAPACITY OF FLOOD AND WATERLOGGING IN THE TYPICAL AGRICULTURAL REGION IN JIANGHAN PLAIN

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Chinese Geographical Science 2001年第3期11卷 68-72页

作者： wang xue-{2. 1,2.,liu Xing-tu 2.,hu wang-bing 1 (1.{2. of geodesy and geophysics,the Chinese Academy of Sciences,wuhan 430077,P.R.china 2.Changchun {2. of Geography,the Chinese Academy of Sciences,Changchun 13002.,P.R.china) institute of geodesy and {2. the Chinese Academy of Sciences Wuhan P. R. China Changchun institute of Geography the Chinese Academy of Sciences Changchun P. R. China

The Jianghan plain is one of the important bases of china’s agricultural productivity,located in central and southern hubei province in the mi ddle reach of Yangtze *** Jian ghan Plain is the one region of flood a nd waterlog-ging occurring *** area is low-lying and is characterized by deep alluvial deposits,many smalle r rivers and numerous larger and shallow lakes fo rmed by meandering of the Changjiang(Yangtze)*** alluvial plain is a honey-comb of waterways bordered by natura l levees,and the depressional areas encompassed by these waterways are dish-shaped in *** s ystems of rivers and lakes are main we tland types in this *** to wetlands in Jianghan plain-lake district fulfill the function related to the flood r egulation,the estimating of the sto rage capacity is use-ful to controlling and reducing the d isasters of flooding and *** this paper,by selecting typic al experimental area,based on its DEM,the relation a mong the water level,area and volume of inundation in the typical region i s de-fined by using regression *** on the agricultural cultivating line in this region and the experim ent result of bear-ing the inundation for crop,we defin e the storage capacity of the typical region in Jianghan Plain -Lake distr ict.

关键词： Jianghan Plain storage capacity simulation agricultural region

The Agricultural Assessment of Climatic Resource and Modeling in Jianghan Plain-Lake District

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wuhan University Journal of Natural Sciences 1999年第4期4卷 423-427页

作者： wang xue {2. 1, WU Yi jin 2. liu gong hu 1 1. {2. of geodesy & geophysics, Chinese Academy of Sciences, wuhan 430077, china 2. Department of History, University of wuhan, wuhan 430077, china Chinese Academy of Sciences Institute of Geodesy &amp geophysics Wuhan China (GRID:grid.9227.e) (ISNI:***) University of wuhan Department of History Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The feature of the climatic resource and the agricultural assessment in Jianghan plain lake district are discussed. In order to exploit the climatic resource, we have recommended some three dimensional agriculture development models in this region according to the types of land use, such as paddy field ecological zone, dry land ecological zone, outskirts ecological zone of the city, waterbody ecological zone, woodland ecological zone.

关键词： Jianghan plain climatic resource assessment modeling

Simulation of the Earth' s gravitational field recovery from GRACE using the energy balance approach

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Progress in Natural Science:Materials International 2005年第7期15卷 596-601页

作者： ZHENG Wei, LU Xiaolei, HSU Houtse, SHAO Chenggang, LUO Jun and wang Nengchao ( Department of Physics, {2.azhong University of Science and Technology, wuhan 430074,{2. institute of geodesy and geophysics, Chinese Academy of Sciences, wuhan 430077,{2. Department of Mathematics, {2.azhong University of Science and Technology, wuhan 430074,{2.) Department of Physics Huazhong University of Science and Technology Wuhan 430074 China. Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 China. institute of geodesy and {2. Chinese Academy of Sciences Wuhan 430077 China

Based on the measurement principles of GRACE satellites, the observation equations are set up using the energy balance approach. The Earth's gravitational field complete up to degree and order 12. is recovered applying the preconditioning conjugate gradient iterative approach by numerical simulation. Assuming an accuracy of 1 μm/s in range-rate measurements of the K-band microwave ranging system, the matching relationships of accuracies of K-band microwave ranging system, SuperSTAR Accelerometer, position vector and velocity vector measurements are investigated.

关键词： the Earth’s gravitational field GRACE satellites energy balance approach preconditioning conjugate gradient method.

Separation of systematic errors in processing high precision GPS baselines

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中国有色金属学会会刊：英文版 2005年第S1期15卷 139-141页

作者： wang Zhen-jie~(1, 2., QU Guo-qing~2.(1. institute of Architectural Engineering, Shangdong University of Technology, Zibo 2.5012.{2. 2. institute of geodesy and geophysics, Chinese Academy of Sciences, wuhan 430077,china) Shandong Univ Technol Inst Architectural Engn Zibo 255012 Peoples R China Chinese Acad Sci Inst Geodesy & Geophys Wuhan 430077 Peoples R China

The research is based on the double difference observations and semi-parametric model. Systematic errors are considered as the parameters to be estimated, and brought into the GPS observation equations. High precision baselines are obtained after separating systematic errors. The crucial steps are choosing regularizer and regularization parameters in processing GPS systematic errors by using the semi-parametric model. We propose a new regularizer and apply it to dealing with systematic errors. Also, we compare it with one proposed by other researchers. This comparison is done when all the regularization parameters equal to one. The computation result of the example shows that two regularizers correspond well and they can separate systematic errors successfully. Thus, we can get high precision baselines. Compared with R=QK-1Q′, our regularizer R=GTG is simple, so, the process of resolving the high precision baselines is relatively simple.

关键词： GPS systematic errors semi-parametric model regularizer

Optimal carrier-smoothed-code algorithm for dual-frequency GPS data

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Progress in Natural Science:Materials International 2008年第5期18卷 591-594页

作者： Jianfeng Guo a,b, Jikun Ou a, Yunbin Yuan a, Haitao wang a a Key Laboratory of Geodynamics, institute of {2. and geophysics, Chinese Academy of Sciences, wuhan 430077, china b institute of Science, Information Engineering University, Zhengzhou 450001, china Key Laboratory of Geodynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China institute of Science Information Engineering University Zhengzhou 450001 China

Carrier-smoothed-code (CSC) algorithm is an e ective pseudorange multipath mitigation technique, which can alleviate the compu- tational burden and reduce the communication bandwidth needed for the transmission of GPS observations. This paper presents an improved Hatch lter and addresses the optimal CSC algorithm for dual-frequency GPS data based on the optimal parameter estimation theory. The smoothed observations have the same information content as that of the raw dual-frequency GPS data from which these are derived. Consequently, the optimal CSC algorithm is equivalent to the uncombined algorithm. Theoretical analyses show that the data precision of the optimal CSC algorithm is better than that of Hatch lter and its improved version.

关键词： GPS Carrier-smoothed-code algorithm Hatch lter Time-invariant combinations

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希夏邦马峰淡色花岗岩岩石成因初步研究

岩石学报 2024年第5期40卷 1446-1460页

作者：刘小驰杨雷何少雄胡方泱王佳敏岩石圈演化国家重点实验室中国科学院地质与地球物理研究所北京100029 成都理工大学地球科学学院成都610059 中国科学院矿产资源研究重点实验室中国科学院地质与地球物理研究所北京100029

淡色花岗岩是研究碰撞造山带地球动力学过程的重要对象。本文对喜马拉雅造山带希夏邦马峰海拔5800m大本营附近的淡色花岗岩样品进行了独居石U-Th-Pb年代学和全岩地球化学初步分析。研究样品根据矿物组合可分为黑云母花岗岩和二云母花岗... 详细信息

淡色花岗岩是研究碰撞造山带地球动力学过程的重要对象。本文对喜马拉雅造山带希夏邦马峰海拔5800m大本营附近的淡色花岗岩样品进行了独居石U-Th-Pb年代学和全岩地球化学初步分析。研究样品根据矿物组合可分为黑云母花岗岩和二云母花岗岩,二者地球化学特征以及变形程度都有所差异,全岩地球化学中弱变形的黑花岗岩表现出低Si和富Al、Mg、Fe、K、Ti的特征,铝饱和指数A/CNK为1.06;强变形和弱变形的二云母花岗岩均表现出高Si和贫Mg、Fe、K、Ti的特征,A/CNK为1.11~1.17。同黑云母花岗岩相比,二云母花岗岩稀土元素中Eu元素负异常明显,微量元素中富集Sn、U,亏损Ba、Sr、Zr、Hf、LREE等元素,暗示岩浆经历了斜长石、黑云母、锆石、独居石和磷灰石的分离结晶作用。黑云母花岗岩和二云母花岗岩中的独居石给出U-Th-Pb年龄为2..9±0.2.a、2..7±0.5Ma和2..7±0.7Ma的一致结果,这一年龄略早于前人报道的结果,指示藏南拆离系活动时间在该区域与喜马拉雅中段具有一致性。本文认为希夏邦马淡色花岗岩岩浆作用与碰撞后伸展阶段发育的藏南拆离系活动具有同时性。

关键词：淡色花岗岩喜马拉雅希夏邦马峰 U-Th-Pb年龄藏南拆离系分离结晶