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Two types of changes in apparent resistivity in earthquake prediction

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Science china Earth Sciences 2011年第1期54卷 145-156页

作者： DU XueBin1,2 1Lanzhou Institute of Seismology, china Earthquake administration, Lanzhou 73.000, china 2Lanzhou Base of Earthquake Science Institute, china Earthquake administration, Lanzhou 73.000, china 1. Lanzhou Institute of Seismology China Earthquake Administration Lanzhou 730000 China2. Lanzhou Base of Earthquake Science Institute China Earthquake Administration Lanzhou 730000 China

Two types of changes in apparent resistivity (AR) have been linked to earthquake occurrences. This paper studies the changes and their causes, in detail with the ultimate purpose of developing and assessing a method of earthquake (EQ) prediction. The AR changes of the first type (CFT) are considered to be precursors related to earthquakes (EQs); these appear mostly in the medium-term period before EQs and in the short-term period preceding EQs. The changes of the second type (CST) are characterized by a turning anomaly of a long-trend AR variation or the drastically descending/ascending anomaly superimposed on such a variation; these appear synchronously in large areas, such as the Chinese mainland, and northern and northwestern china, ect. Their spatio-temporal clusters correspond well to high seismicities in the areas and distant great EQs around the Chinese mainland. Based on the behaviors of the two types of changes, the AR changes observed prior to the Ms8.0 Wenchuan EQ of 2008 are studied. The results show that in the medium-term period before the EQ, noticeable anomalies appeared synchronously at four stations around the Songpan-Ganzi active block, but only weak upward changes were observed in the short-term period preceding the EQ, which caused the prediction of the imminent EQ to fail.

关键词： strong earthquake apparent resistivity two types of changes spatio-temporal cluster Wenchuan earthquake

Ecological-sedimentary zonations and carbonate deposition,Xiaodonghai Reef Flat,Sanya,Hainan Island,china

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Science china Earth Sciences 2011年第3期54卷 359-371页

作者： WANG Yue1,2, SHEN JianWei1 & LONG JiangPing3.1 Department of Marine Geology, South china Sea Institute of Oceanology CAS Key Laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 5103.1, china 2 Graduate University of Chinese Academy of Sciences, {3. 100049, china 3.The Second Institution of Oceanography, State Oceanic administration, Hangzhou 3.0012, china 1. Department of Marine Geology South China Sea Institute of Oceanology Guangzhou China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China4. CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China3. The Second Institution of Oceanography State Oceanic Administration Hangzhou 310012 China

Modern fringing reefs are developed on the intertidal to subtidal area of Xiaodonghai bay, Sanya, Hainan Island. The reef flat extends several dozen meters toward the sea. Various ecological and sedimentary zonations can be distinguished, including, from land to sea, beachrocks, large massive corals, inner reef flat, outer reef flat, and fore-reef slope. The carbonate sediments and constituent hermatypic coral communities are different in these zones. The beachrocks are composed mainly of biological sands, including coral skeletons, algae, gastropods, bivalves, and benthic foraminifera. Quartz sands are less common in this zone. Carbonate diagenesis in beachrocks is characterized by early cementation. The fringing reef flat is progradationally developed toward the sea. Large massive corals grew in the zone next to the beachrocks. These corals are large, flat-toped, and autochthonous in the production of bioclastic grains and lime mud. Large and massive coral skeletons are surrounded by coral skeletal grains, bioclasts, and lime-mud sediments. The inner reef flat consists mainly of skeletons of branching corals that are covered by bioclasts and lime mud, and living corals are mostly massive in form. Statistical analysis of coral-community dynamics shows that the outer reef flat with strong waves is the most suitable place for hermatypic corals to flourish. There, the living corals are most densely distributed. Both massive corals and branching corals (e.g., Acropora corymbosa) are exceptionally healthy in this zone. Bioclasts and lime mud are washed out due to strong wave action. Microbial carbonates generally are deposited within cavities of the beachrocks and coral skeletal cavities and on the surfaces of bioclastic grains. The latter two types, however, are more common. Ecological-sedimentary zonations across the Xiaodonghai reef flat from beachrocks to outer reef flat are controlled by variations in wave strength and water energy. Microbial carbonates rarely deve

关键词： microbial carbonates ecological-sedimentary zonation cementation reef flat Hainan Island

EVALUATION OF WATER AND SEDIMENT QUALITIES AT RIVER MOUTHS IN THE HAIHE RIVER SYSTEM

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International Journal of Sediment Research 2007年第4期22卷 318-326页

作者： Cheng LIU1, Zhao-Yin WANG1,2, Yun HE3. and Dongsheng CHENG3.1 Prof., Dr., International Research and training Center on Erosion and Sedimentation, beijing, 100044, china 2 Prof., Dr., Dept. of Hydraulic Engineering, Tsinghua University & International Research and training Center on Erosion and Sedimentation, beijing, 100084, china 3.Dr., Senior Engineer, china Institute of Water Resources and Hydropower Research, beijing, 100044, china Int Res & training Ctr Eros & Sedimentat Beijing 100044 Peoples R China Tsinghua Univ Dept Hydraul Engn Beijing 100084 Peoples R China Int Res & training Ctr Eros & Sedimentat Beijing 100084 Peoples R China china Inst Water Resources & Hydropower Res Beijing 100044 Peoples R China

Water and sediment qualities are studied by analyzing samples taking from the mouths of the Haihe, Duliujian, New Ziya and Beipai rivers in the Haihe river basin in north china in 2005 and 2001, in order to find the changes of water and sediment pollutions. The concentrations of heavy metals, arsenic, total nitrogen (TN) and total phosphorus (TP) are analyzed and results have been compared for the two times. The in-situ measurement for Dissolved Oxygen (DO) and Sediment Oxygen Demand (SOD) rates were carried at the Haihe and Duliujian river mouths in 2006. The results show that the waters of the 4 river mouths are still seriously polluted, though much improved in the case of the Haihe and Duliujian rivers. The main pollutants are TP and TN in the New Ziya and Beipai rivers and mercury (Hg) at all 4 river mouths. Compared with those in 2001, the concentrations of almost all metals and arsenic in the 4 river mouths have decreased. Water quality at Haihe and Duliujian shows an improving trend, while the water quality at Beipai is similar to that of 2001. In contrast, water at the New Ziya river mouth is more severely polluted. The sediments in the 4 river mouths are not seriously polluted by heavy metals but are polluted by nitrogen and phosphorus. Most of the pollutant contents in the sediments show little change between 2001 and 2005. The in-situ DO and SOD measurement shows that the waters at the Haihe river mouth is in the state of oxygen depletion, and SOD is important consumer of DO at the river mouths. The overall analysis shows that increasing water pollution and eutrophication in waters far from cities are ongoing causes of concern.

关键词： River mouth Water quality Sediment quality Eutrophication Sediment oxygen demand

Mineral provinces and material provenance of the surficial sediments near the Zhongsha Islands in the South china Sea

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Acta Oceanologica Sinica 2007年第1期26卷 66-76页

作者： YAN Quanshu1, 2, 3. SHI Xuefa2*, WANG Kunshan21. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, china2. Key Laboratory of Marine Sedimentology and Environment Geology of State Oceanic administration, First Institute of Oceanograghy, State Oceanic administration, Qingdao 266061, china3. Graduate School, Chinese Academy of Sciences, beijing 100049, china Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

Characteristics and distribution patterns of clastic minerals (0.063.0.125 mm) in bottom sediments represent a significant indicator for the identification of the origin of sediment. One hundred and fourteen surface sediment samples, which were collected from the area near the Zhongsha Islands in the South china Sea, were analysed to identify the mineral suites and their distributions in the study area. The area can be divided into three mineral provinces: (Ⅰ) a province of biogenic minerals, which mainly originate from the Zhongsha Atoll; (Ⅱ) a province of volcanogenic minerals, which are mainly derived from local basaltic seamounts and small-scale volcanoes that are probably erupting, with some influences from the island-arc volcanic region around the South china Sea; and (Ⅲ) a mixed mineral province whose material source includes biogenic minerals, volcanogenic minerals and terrigenous minerals; the last province can be subdivided into a mixed mineral sub-province of the northeastern part of the study area, in which terrigenous minerals are mainly derived from china’s Mainland and do not exceed 17°N, and a mixed mineral sub-province of the southeastern part of the study area, in which terrigenous minerals are derived from Kalimantan and Indochina Peninsula and might be further transported into the deep sea basin through submarine canyons.

关键词： South china Sea Zhongsha Islands light mineral minerals province material provenance

Building damage in Dujiangyan during Wenchuan Earthquake

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Earthquake Engineering and Engineering Vibration 2008年第3期7卷 263-269页

作者： Zhang Minzheng and Jin Yingjie Institute of Engineering Mechanics, china Earthquake administration, Harbin 150080, china Professor Graduate Student Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China

A field damage survey of 1,005 buildings damaged by the Wenchuan Earthquake in Dujiangyan City was carried out and the resulting data was analyzed using the statistical method. It is shown that buildings that were seismically designed achieved the desired seismic fortification target; they sustained less damage than the non-seismically designed buildings. Among the seismically designed buildings investigated, RC frame buildings performed the best in terms of seismic resistance. Masonry buildings with a ground story of RC frame structure were the second best, and masonry buildings performed the worst. Considering building height, multistory buildings sustained more severe damage than high-rise buildings and 2- and 3.story buildings. Compared to residential buildings, public buildings, such as schools and hospitals, suffered more severe damage.

关键词： Wenchuan Earthquake Dujiangyan building damage seismic intensity field survey

Total control-based unified allocation model for allowable basin water withdrawal and sewage discharge

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Science china(Technological Sciences) 2010年第5期53卷 1387-1397页

作者： HU SiYi1,2,WANG ZongZhi1,WANG YinTang1 & ZHANG LingLing3.1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing Hydraulic Research Institute,Nanjing 210029,china 2 Ministry of Water Resources,the People’s Republic of china,beijing 100053.china 3.School of Public administration,HoHai University,Nanjing 210098,china 1. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210029 China2. Ministry of Water Resources the People’s Republic of China Beijing 100053 China3. School of Public Administration HoHai University Nanjing 210098 China

In this paper,a new model with a total amount control target of allowable water withdrawal based on initial water right is built for the implementation of initial water right allocation scheme as well as unified allocation for allowable water withdrawal and sewage *** model couples the water allocation simulation model and the computational model of permissible pol-lution bearing *** view of the model complexity,a new technology which synthesizes system simulation,iterative reservoir turns and intelligent computation is proposed to improve the operability of allocation scheme and computational *** the Beijiang River Basin in the Pearl River Basin as an example,the study explains the model establishment,solution and application,and draws an optimized operation graph of large-scale *** study also obtains a long-term operation strategy of river basin water resources system,the allocation schemes of allowable water withdrawal and sewage discharge in a typical year and the flow hydrographs of trans-boundary *** validity of the model and the allocation rationality are analyzed as well.

关键词： water resources management total control unified control of water withdrawal and sewage discharge optimized regulation integration technology

Eleventh Five-Year Plan for Space Science Development

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空间科学学报 2008年第5期28卷 499-505页

作者： china National Space administration china National Space administration

Preface Space science is a discipline to study the universe,to investigate the fundamental process of molecules and atoms,and reveal,at the underlying roots,the laws of the external world.

关键词：第十一个五年计划空间科学空间计划研究进展

Preliminary analysis of the hanging wall effect and velocity pulse of the 5.12 Wenchuan earthquake

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 165-177页

作者： Liu Qifang and Li Xiaojun Institute of Engineering Mechanics, china Earthquake administration, Harbin 150080, china Associate Professor Professor Institute of Engineering Mechanics China Earthquake Administration Harbin 150080 China Institute of Engineering Mechanics China Earthquake Administration 9 Xuefu Road Harbin 150080 China

A preliminary study of the PGA attenuation, hanging wall effect and velocity pulse characteristics from the 2008 Wenchuan earthquake ofMS -8.0 is described in this paper. The study was carried out through analyses in the time and frequency domains of main earthquake records. In the PGA attenuation study, records from 3.6 stations less than 1000 km from the surface rupture of the fault were used as a database and attenuation relationships were developed and compared with some existing relationships that are widely used in china's Mainland, Chinese Taiwan and the US. At the same time, records from 28 stations less than 100 km from the fault were used to study the hanging wall effect and velocity pulse characteristics of this earthquake based on the distribution of PGA, PGV, spectral acceleration, and the velocity pulse peak, and the results are compared with the 1999 Chi-Chi earthquake. In addition, the large PGAs of the UD components observed in this event are also discussed in this paper. From the results of the preliminary study, some conclusions are developed and suggestions for further research are proposed.

关键词： Wenchuan earthquake hanging wall effect velocity pulse attenuation

The HY-1 satellite and ground system in china

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Acta Oceanologica Sinica 2003年第2期22卷 301-308页

作者： Liu Jianqiang , Jiang Xingwei, Lin Mingsen National Satellite Ocean Application Service of State Oceanic administration, beijing 1.0081. china, State Ocean Adm Natl Satellite Ocean Applicat Serv Beijing 100081 Peoples R China

INTRODUCTIONWith the coming of the 21st century, we are faced the problems of the environment, re-sources and population. The ocean is regarded as supplier of resources such as food, minerals,energy and space, and plays an important role in sustainable economic development. At thesame time the ocean has a very important effect on the worldwide environmental changes.

关键词： HY-1 satellite ground system china