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Progress in Earthquake Science and Technology in china: Review and Prospects (Ⅲ)

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Earthquake Research in china 2002年第1期16卷 95-112页

作者： Chen Zhanglichina seismological bureau, beijing 100036,{4. china seismological bureau Beijing 100036China

*** CONCEPTION AND PROSPECTS TO THE FUTUREAt the time of entering the new century,we should not forget the great havoc to the people caused by earthquakes in china for last hundred *** affirming the great progress in earthquake science and technology in china during last tens of years,especially during the 9th Five-Year Plan,we have clearly known that there exists a large gap between the current scientific-technical capability of earthquake disaster prevention and reduction and the social need for earthquake disaster reduction and mitigation as well as effect of earthquake on social-economic *** the economic development and progress of social civilization,the effect of earthquake disaster on social-economic life tends to be rapidly ***,the task for earthquake disaster prevention and reduction will be more tremendous in the new century.

关键词： Earthquake Science and technology Progress Review and prospect

High-resolution Rayleigh wave phase velocity maps from ambient noise tomography in North china

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Earthquake Science 2012年第3期25卷 241-251页

作者： Jiatie Pan institute of Geophysics, china Earthquake Administration, beijing 100081, china institute of Geophysics China Earthquake Administration Beijing China

We presented high-resolution Rayleigh wave phase velocity maps at periods ranging from 5 s to 30 s in the northeast part of the North china Craton (NNCC). Continuous time-series of vertical component between October 2006 and December 2008, recorded by 187 broadband stations temporarily deployed in the NNCC region, have been cross-correlated to obtain estimated fundamental mode Rayleigh wave Green’s functions. Using the frequency and time analysis technique based on continuous wavelet transformation, we measured 3 667 Rayleigh wave phase velocity dispersion curves. High-resolution phase velocity maps at periods of 5, 10, 20 and 30 s were reconstructed with grid size 0.25°× 0.25°, which reveal lateral heterogeneity of shear wave structure in the crust and upper mantle of NNCC. For periods shorter than 10 s, the phase velocity variations are well correlated with the principal geological units in the NNCC, with low-speed anomalies corresponding to the major sedimentary basins and high-speed anomalies coinciding with the main mountain ranges. Within the period range from 20 s to 30 s, high phase velocity observed in eastern NCC is coincident with the thin crust, whereas low phase velocities imaged in central NCC is correlated to the thick crust. However, the low-velocity anomaly in the beijing-Tianjin-Tangshan region displayed in the 20 s and 30 s phase maps may be associated with fluids.

关键词： Rayleigh wave phase velocity ambient noise tomography wavelet transformation North china Craton

Ecological response to the climate change on the northern slope of the Tianshan Mountains in Xinjiang

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Science china Earth Sciences 2005年第6期48卷 765-777页

作者： CHEN Xi1, LUO Geping1, XIA Jun2, ZHOU Kefa1, LOU Shaoping3 & YE Minquan4.1. Xinjiang institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, china 2. institute of Geographical and Resources Sciences, Chinese Academy of Sciences, beijing 100101, china 3. Urumqi Meteorological-satellite Land Station, Urumqi 830011, china 4. seismological bureau of Xinjiang Uygur Autonomous Region, Urümqi 830011, china Correspondence should be addressed to Chen Xi Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China institute of Geographical and Resources Sciences Chinese Academy of Sciences Beijing China Urumqi Meteorological-satellite Land Station Urumqi China seismological bureau of Xinjiang Uygur Autonomous Region Urümqi China

The Tianshan Mountains is a high and huge mountain body lying across the central part of Xinjiang, china, and is also the main area where the runoff forms in Xinjiang. In this paper, a set of RS-based study methods is put forward for deriving the information about the natural change of the ecology in arid areas, and the relationship between the climate change trend and the corresponding ecological response on the northern slope of the Tianshan Mountains since recent 4. years is analyzed from the scales of the land cover ecosystems and landscapes based on the observed data of climate, hydrology, modern glaciers and lakes on the northern slopes of the Tianshan Mountains since recent 4. years and the satellite RS data since recent 10 years by using the RS and GIS technologies. The results are as follows: (1) The overall trend of climate change on the northern slope of the Tianshan Mountains since recent 4. years is that both air temperature and precipitation are increased, especially the increase amplitudes of air tempera-ture, precipitation and annual runoff volume are high since the decade of the 1990s; (2) the in-tegrated indexes of the vegetation in all the geographical divisions on the northern slope of the Tianshan Mountains are obviously increased since recent 10 years, especially in the artificial oases and the foothill belts, such a change trend is advantageous for improving the vegetation ecology; and (3) the vegetation ecology in the arid areas is extremely sensitive to the climate change, the vegetation coverage and the biomass on the northern slope of the Tianshan Moun-tains are continuously increased because of the climate change since recent 10 years, their in-crease amplitudes in the plains and during the late stage are obviously higher than that in the mountainous regions and during the early stage.

关键词： north slope of the Tianshan Mountains, climate change, hydrological change, natural change of ecology,RS and GIS, vegetation index.

Progress in Earthquake Science and Technology in china: Review and Prospects (I)

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Earthquake Research in china 2001年第4期15卷 329-345页

作者： Chen Zhanglichina seismological bureau, beijing 100036,{4. china seismological bureau Beijing 100036 China

In the article the author looks back the hard development course and great progress in earthquake science and technology in china during the last near a half of century and expounds the following 3 aspects: (1) The strong desire of the whole society to mitigate seismic disasters and reduce the effect of earthquakes on social-economic live is a great driving force to push forward the development of earthquake science and technology in china; (2) To better ensure people’s life and property, sustainable economic development, and social stability is an essential purpose to drive the development of earthquake science and technology in china; and (3) To insist on the dialectical connection of setup of technical system for seismic monitoring with the scientific research of earthquakes and to better handle the relation between crucial task, current scientific level, and the feasibility are the important principles to advance the earthquake science and technology in china. Some success and many setbacks in earthquake disaster mitigation consistently enrich our knowledge regarding the complexity of the conditions for earthquake occurrence and the process of earthquake preparation, promote the reconstruction and modernization of technical system for earthquake monitoring, and deepen the scientific research of earthquakes. During the last 5 years, the improvement and modernization of technical system for earthquake monitoring have clearly provided the technical support to study and practice of earthquake prediction and precaution, give prominence to key problems and broaden the field of scientific research of earthquakes. These have enabled us to get some new recognition of the conditions for earthquake occurrence and process of earthquake preparation, characteristics of seismic disaster, and mechanism for earthquake generation in china’s continent. The progress we have made not only encourages us to enhance the effectiveness of earthquake disaster mitigation, but also provides

关键词： Earthquake Science and technology Progress Review and prospect

Progress in Earthquake Studies in china for the Past 30 Years

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Earthquake Research in china 1996年第1期10卷 4-18页

作者： Chen ZhangliState seismological bureau,beijing 100036,china

Progress and application of earthquake studies are important and effective fundamentals for the improvement of earthquake prevention and disaster reduction. Through industrious effort during the past 30 years, significant advances were made in understanding the rules of earthquake occurrence, and the mastering and applying of the technology of earthquake prevention and disaster reduction. A number of devices that come close to or reach advanced world levels have been established and some systems in seismological experiments and earthquake prevention work have been improved, the ability to test and identify earthquake precursors have been raised, and the understanding of the complexity of these precursors has been deepened. The practical indexes and approaches for earthquake prediction have been worked out, and remarkable achievements in predictions and prevention of major earthquakes have

关键词：名言苦口

Preparedness and Mitigation of Urban Earthquake Disaster in china

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Natural Disaster Reduction in china 2000年第1期 23-25页

作者： HE Yongnian (china seismological bureau, beijing 100036,{4.)

chinais***,betweentwobiggestearthquakebelts,theCir***... 详细信息

chinais***,betweentwobiggestearthquakebelts,theCir***...

关键词： preparedness mitigation earthquake

SHRIMP zircon U-Pb age and Nd isotopic study on the Nyainqêntanglha Group in Tibet

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Science china Earth Sciences 2005年第9期48卷 1377-1386页

作者： HU Daogong1, WU Zhenhan1, JIANG Wan1, SHI Yuruo2, YE Peisheng1 & LIU Qisheng1 1. institute of Geomechanics, Chinese Academy of geological Sciences, beijing 100081, china 2. institute of Geology, Chinese Academy of geological Sciences, beijing SHRIMP Centre, beijing 100037, china institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of Geology Chinese Academy of Geological Sciences Beijing SHRIMP Centre Beijing China

The Nyainqêntanglha Group is traditionally viewed as the oldest metamorphic basement in the Lhasa block, but its formation age and tectonic setting remain debate. Zircons extracted from the metamorphic sequence of volcanics and intrusions of the Nyainqêntanglha Group, 10 km west of Nam Co in northern Lhasa block, have been investigated by cathodolu- minescence (CL), backscattered (BSE) and dated by ion microprobe (SHRIMP). We conclude that the U-Pb age of 787±9 Ma of zircons from the trondhjemite imposes a constraint on maxi- mum protolith age, and minimum formation age of the Nyainqêntanglha Group is constrained by U-Pb age of 74.±8 Ma of zircons from the granite. The formation age of the Nyainqêntanglha Group is consistent with sedimentary age of Greater Himalayan rocks, showing that they devel- oped coevally in an arc-basin tectonic setting of Neoproterozoic active continental margin along the northern margin of the India shield. The inherited zircons from the tholetiite and granite give older 207Pb/206Pb ages from 94. to 1766 Ma. The positive εNd( t ) value indicates that the mafic rocks were derived from the depleted mantle, but contaminated by the older continental crustal material. Integrated Nd model age and U-Pb age data provide excellent evidence for the exis- tence of Mesoproterozoic basement in the Lhasa block during Neoproterozoic time.

关键词： Nyainqêntanglha Group, SHRIMP dating, Nd isotope, Neoproterozoic, Tibet.

Zhang-Xuan thermal uplift and its genesis

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Progress in Natural Science:Materials International 2005年第8期15卷 725-732页

作者： SHAO Ji'an1*, NIU Shuyin2, ZHANG Lüqiao3 and LI Hongyang2(1. School of Earth and Space Sciences, Peking University, beijing 100871, china 2. Shijiazhuang University of Economics, Shijiazhuang 050031, china 3. geological {4. of Inner Mongolia, Huhhot 010020, china) School of Earth and Space Sciences Peking University Beijing 100871 China Shijiazhuang University of Economics Shijiazhuang 050031 China geological bureau of Inner Mongolia Huhhot 010020 China

Based on the researches of the Mesozoic thermal evolution history, the deformed structures, and fission track analysis of the Zhangjiakou-Xuanhua area, we obtained the following knowledge: the area experienced in 14. Ma an underplating which is marked by emplacement of mantle derived magma; during 130—110 Ma a series of eruptions and intrusions happened, and during 80—10 Ma a rising process occurred which is synchronous with the adjacent Taihang and Yanshan Mountains and was accompanied by a series of structures down slipping from the just formed Zhang-Xuan uplift toward its periphery. Combining the Zhang-Xuan thermal lift with the large detachment structure in Baoding depression of the North china Basin in the Late Mesozoic confirms that an even larger extensional tectonic background existed in North china during this period.

关键词： Zhang-Xuan area underplating thermal uplift fission track extensional structure.

A new method for spatio-temporal prediction of rainfall-induced landslide

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Science china Earth Sciences 2006年第4期49卷 421-430页

作者： DING Jixin1,2, YANG Zhifa2, SHANG Yanjun2, ZHOU Shenghua1 & YIN Juntao3 1. china Non-ferrous Metals Resource geological Survey, beijing 100012, china 2. {4. of Geology and Geophysics, Chinese Academy of Sciences, Key Laboratory of Engineering Geomechanics, beijing 100029, china 3. School of Geoscience & Environmental Engineering, Central South University, Changsha 4.0083, china china Non-ferrous Metals Resource geological Survey Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Key Laboratory of Engineering Geomechanics Beijing China School of Geoscience & Environmental Engineering Central South University Changsha China

geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal prediction of rainfall-induced landslide is brought forward on the basis of grading and overlapping geological condition and rainfall factor in this paper. At first, semi-quantitative assessment and grading for the geological condition of a certain area or slope can be carried out with the multi-factor interactive matrix. Then the severity of rainfall in that area is grading according to the maximum daily rainfall and the total rainfall in a rainfall course. Finally, the “landslide probability judgement factor” can be worked out through grading and overlapping “geological condition influenc- ing factor” and “rainfall influencing factor”, by which the landslide can be graded into 4.grades, they are landslide extremely easily happening, landslide easily happening, landslide difficultly happening and landslide hardly ever happening respectively. More accurate spatio-temporal prediction of rain- fall-induced landslides can come true on the ground of detailed geological survey of some dangerous slopes in an area and more precise weather forecast. Finally, the reliability and feasibility of carrying out the spatio-temporal prediction of rainfall-induced landslides with the method of “two factors” grading and overlapping are validated by the example of Jipazi landslide.

关键词： rainfall-induced landslide, geological condition, rainfall, two factors, grading and overlapping, interactive matrix, spatio-temporal prediction.