Extracting coseismic deformation of the 1997 Mani earthquake with differential interferometric SAR

Introduction The development and application of Interferometric Synthetic Aperture Radar (InSAR) have a close relationship with the sensors development of Synthetic Aperture Radar (SAR). The conception of SAR is proposed comparatively to the real aperture radar antenna. It is well known that the longer the antenna is, the higher the observation resolution will be. Just limited by the length of the antenna, the resolution of real aperture radar is generally very low and cannot meet the r…     

20世纪地震预报科学的回顾与展望

在新世纪的到来,对２０世纪的地震研究作一些回顾,对中国几十年的地震预报的道路进行反思,可能是很有意义的,这对我们编制“十五”规划也有借鉴。     

Evaluation of land subsidence by considering underground structures that penetrate the aquifers of Shanghai, China

Underground structures that penetrate into aquifers can cause groundwater-level drawdown and land subsidence. Numerical analyses, based on a three-dimensional (3-D) groundwater flow model incorporated with a 1-D consolidation model, have been conducted to assess the behaviour of seepage and effect on subsidence by considering underground structures in the multi-aquifer?Caquitard system of Shanghai, China. Two extreme scenarios were examined: (1) distributed underground structures, and (2) concentrated underground structures around the heavily urbanized area. In the first scenario, the aquifer with underground structures was substituted with another material that possessed a lower hydraulic conductivity, established using the effective-medium theory; when the ratio of the volume of the underground structures to that of selected aquifer layers??(1) low-pressure partially-confined aquifer (Aq02), (2) the first confined aquifer (AqI), and (3) the second confined aquifer (AqII)??increases by 10?%, subsidence increases by about 3, 3 and 32?%, respectively. In the second scenario, part of the aquifer material was directly replaced by the structure material (very low hydraulic conductivity). In this situation, when the ratio of the volume of the underground structure to the volume of aquifers Aq02, AqI or AqII increases by 10?%, subsidence increases by about 5, 8 or 20?%, respectively.     

关于台风风场研究进展的若干问题探讨

台风是对我国造成严重危害的中尺度天气系统,随着沿海地区经济的发展以及越来越多的海洋开发工程的进行,对台风的研究也日益受到重视。本文从台风的观测、理论和数值研究几个方面综合分析了台风研究中的若干问题,并对现阶段存在的问题进行了讨论。     

新疆哈图金矿微球粒的发现及其地质意义

采自新疆哈图金矿区各地层单元和含矿脉体中的基岩人工重砂样品普遍含有一种“微球粒”物质。通过“微球粒”的一般特征，表面、断面结构、矿物组成和化学成分的研究，认为属消融型宇宙尘。并据此提出区内玄武质母岩浆在形成玄武岩的过程中同化、熔融了含宇宙尘的局部老地层物质；为区内金矿化提供含矿热液的花岗岩属重熔型花岗岩。     

The expert system for earthquake prediction (I)—the overall design and main structure

The Expert System For Earthquake Prediction (ESEP) is summarized in this paper. ESEP embraces three subsystems: long-middle term prediction system, annual prediction system and middle-short term prediction system. Each of the subsystems is composed of seven modules: the controlling module, the data base module, the expert knowledge base module, the method base module, the fact preparation module, the reasoning and decision-making module and the plotting and displaying module. The reasoning model ESEP/R and the knowledge expression model ESEP/K are set up in the ESEP, and new evidence combinations, CON (confine), W (weigh), and SYN (synthesize), have been proposed. The distinctive features of the ESEP are: (1) systemized; (2) several experts’ knowledge can be synthesized; (3) a large amount of data and experts’ experience is embraced; (4) four reasoning models and the synthetic decision-making technic are adopted; (5) several software environments are used; (6) modularization; and (7) possessing the friendly user interfaces. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, 1–8, 1992.     

Theoretical and experimental study on relationship between stress-strain and temperature variation

Principle on temperature response to the stress-strain variation is fundamental to the relationship between thermal radiation variation and stress-strain field. Current research indicates that temperature has a sensitive response to rock deformation under the condition of normal temperature background. However, the basic physical relationship between deformation and temperature variation is not clear and need to be investigated further. In this paper, principle on temperature response to stress-strain variation is studied in detail, based on thermodynamics, elastic strain theory, and experiments on both ideal material and rock. In the stage of elastic deformation, results indicate that: 1) temperature increment is positively correlated with volume strain variation. Temperature rises with hydrostatic pressure increase. In other words, temperature rises when the specimen is under the compressive state whereas temperature drops under the tensile state. 2) Pure shear deformation does not contribute to temperature variation. Namely, shape change of specimen does not produce temperature variation. However, there exist the relative tensile area and the compressive one in the specimen under the state of pure shear. Temperature drops within the relative tensile area while temperature rises within the compressive areas during the process of loading.     

上海市区浅层土的沉降计算(考虑次固结影响)

本报告在研究上海市区浅层土固结特性的基础上(见1975年至今的工作报告,采用一种考虑了次固结的沉降计算方法.     

Uncertainty quantification of landslide runout motion considering soil interdependent anisotropy and fabric orientation

Landslides - Natural soils often exhibit an anisotropic fabric pattern as a result of soil deposition, weathering, or filling. This paper aims to investigate the effect of soil interdependent...     

High-velocity frictional behavior of Longmenshan fault gouge from Hongkou outcrop and its implications for dynamic weakening of fault during the 2008 Wenchuan earthquake

High-velocity friction experiments were conducted on clayey fault gouge collected from Hongkou outcrop of Beichuan fault,located at the southwestern part of Longmenshan fault system that caused the disastrous 2008 Wenchuan earthquake.The ultimate purpose of this study is to reproduce this earthquake by modeling based on measured frictional properties.Dry gouge of about 1 mm in thickness was deformed dry at slip rates of 0.01 to 1.3 m/s and at normal stresses of 0.61 to 3.04 MPa,using a rotary-shear high-...