Simultaneous iterative time-domain sparse deconvolution to teleseismic receiver functions

In this paper, we present a new approach to estimate high-resolution teleseismic receiver functions using a simultaneous iterative time-domain sparse deconvolution. This technique improves the deconvolution by using reweighting strategies based on a Cauchy criterion. The resulting sparse receiver functions enhance the primary converted phases and its multiples. To test its functionality and reliability, we applied this approach to synthetic experiments and to seismic data recorded at station ABU, in Japan. Our results show Ps conversions at approximately 4.0 s after the primary P onset, which are consistent with other seismological studies in this area. We demonstrate that the sparse deconvolution is a simple, efficient technique in computing receiver functions with significantly greater resolution than conventional approaches.     

Potential impacts of aerosol–land–atmosphere interactions on the Indian monsoonal rainfall characteristics

Aerosols can affect the cloud-radiation feedback and the precipitation over the Indian monsoon region. In this paper, we propose that another pathway by which aerosols can modulate the multi-scale aspect of Indian monsoons is by altering the land–atmosphere interactions. The nonlinear feedbacks due to aerosol/diffuse radiation on coupled interactions over the Indian monsoon region are studied by: (1) reviewing recent field measurements and modeling studies, (2) analyzing the MODIS and AERONET aerosol optical depth datasets, and (3) diagnosing the results from sensitivity experiments using a mesoscale modeling system. The results of this study suggest that the large magnitude of aerosol loading and its impact on land–atmosphere interactions can significantly influence the mesoscale monsoonal characteristics in the Indo-Ganges Basin.     

A simplified approach for vulnerability assessment in moderate-to-low seismic hazard regions: application to Grenoble (France)

Due to the moderate seismic risks in France, the building vulnerability assessment methods developed for high seismic risk countries could not easily be used here because of their cost and the low-risk perception among the public and officials. A light vulnerability assessment method is proposed and tested in Grenoble (France), based on classes and scores provided in the GNDT method but simplified in terms of visual screening and number of structural parameters used. Compared to the RiskUE method, the damage obtained by our approach shows that 90% of buildings have residuals smaller than 0.2, i.e. one grade of the EMS98 damage scale. A large scale survey is devised and conducted among the inhabitants of Grenoble in order to collect the main structural parameters. By comparing the results from the survey to the historical urbanization of Grenoble and to expert surveys performed in two urban districts, the information useful for the light method of vulnerability assessment can be rapidly collected by non-experts reducing substantially the estimate cost. The average damage is then computed using the GNDT formula considering the probable intensities which could be observed in Grenoble (VII and VIII). The average damage reaches 0.4 in the oldest part of Grenoble mainly made of masonry buildings and 0.2 in reinforced concrete suburbs where reinforced concrete predominates. The results are a relative vulnerability assessment that provides useful initial information for the urban zones of Grenoble where the vulnerability is higher. This method can be used to classify the seismic vulnerability in wide seismic-prone regions to a fair degree of accuracy and at low cost.     

Influence of the Kunlun Mountain Ms8.1 Earthquake on Horizontal Crustal Deformation in the Sichuan and Yunnan Area

In order to track the space-time variation of regional strain field holistically(in a large scale) and to describe the regional movement field more objectively,the paper uses a nonlinear continuous strain model focused on extracting medium-low frequency strain information on the basis of a region with no rotation.According to the repeated measurements(1999～2001～2004) from GPS monitoring stations in the Sichuan and Yunnan area obtained by the Project of "China Crust Movement Measuring Network",and with the movement of 1999～2001(stage deformation background) as the basic reference,we separated the main influencing factors of the Kunlun Mountain M-S8.1 earthquake in 2001 from the data of 2001 and 2004,and the results indicate:(1) the Kunlun Mountain M-S8.1 earthquake has a discriminating effect on the Sichuan and Yunnan area,moreover,the deformation mode and background had not only certain similitude but also some diversity;(2) The movement field before the earthquake was very ordinal,while after the earthquake,order and disorder existed simultaneously in the displacement field;The displacement quantities of GPS monitoring stations were generally several millimeters;(3) The principal strain field before earthquake was basically tensile in an approximate EW direction and compressive in the SN direction,and tension was predominant.After the earthquake,the principal strain field in the Sichuan area was compressive in the EW direction and tensile in the SN direction,and the compression was predominant.In the Yunnan area,it was tensional in the NE direction and compressive in the NW direction,and tension was predominant;(4) The surficial strain before the earthquake was dominated by superficial expansion,the contractive area being located basically in the east boundary of Sichuan and Yunnan block and its neighborhood.After the earthquake,the Sichuan area was surface contractive(the further north,the greater it was),and south of it was an area of superficial expansion.Generally speaking,the Kunlun Mountain M-S8.1 earthquake played an active role in the accumulation of energy in the Sichuan and Yunnan area.Special attention shall be focused on the segment of Xichang-Dongchuan and its neighborhood.     

“9.18”川西北暴雨过程的数值预报与试验

利用成都区域中心ETA坐标模式，对2001年9月18－21日发生在四川盆地西北部的暴雨过程作数值预报试验，显示出对大暴雨过程的预报能力。模式预报对此降水过程雨区的移动、稳定、减弱趋势有较好的反应，但降水强度预报偏弱，且落区有偏差。数值试验揭示了降水前期对流层中、低层的西南、东南气流对降水的重要作用，而北方冷空气的强弱对此影响不明显。     

对山西应县木塔采用纳米复合纤维加固的建议

山西应县木塔是古人留给我们的稀世珍宝，如何妥善地保护好这一珍贵的遗产，使之在加固时尽量保持原有的风貌，是一项复杂而艰巨的任务。根据长期的研究成果和实际工作的经验，提出了用纳米复合纤维加固应县木塔的建议，介绍了纳米复合纤维材料的特点，分析讨论了加固时的一些具体技术问题。     

绿柱石通道中配合物的振动光谱和辐照裂解

以四川平武富碱型绿柱石为研究对象 ,采用 IR和 L RM测试方法 ,重点对通道中氢化物和多聚合离子的配位构型、辐照裂解及热致转型进行了较深入系统的研究。研究表明 ,在该区成矿作用条件下 ,绿柱石通道中的钠离子趋向与氢离子化合反应生成 Na H氢化物 ,并占据通道中的 C2 位。在垂直 c轴方向上 ,以 3165 cm-1,3114 cm-1及 30 31cm-1伸缩振动弱吸收谱带为特征。[Fe2 ( OH) 4 ] 2 多聚合离子占据通道中的 C1位 ,以 32 34 cm-1伸缩振动锐吸收谱带为特征 (∥ c轴 )。辐照作用导致上述多聚合离子的裂解 ,并形成不稳定的 [H0 ] i心和相对稳定的 [Fe3 ] OH心。与之对应的吸收谱带分别出现在 3110 cm-1(⊥ c轴 )和 335 5cm-1(∥c轴 )处。通道中 Na H和 [Fe2 ( OH) 4 ] 2 多聚合离子的存在 ,可视为该类型绿柱石的一个重要的成因标志。     

A new inverse method and application to ocean data

A new method is proposed to inverse normalization data of hidden variables in a dynamical system by embedding a time series in multidimensional spaces and applying a normalization analysis to the conditional probability density of points in the reconstructed phase spaces. The method is robust in the application to Lorenz system and 4-dimensional R?ssler system by testing quantitatively and qualitatively the correlation coefficient between inverse data and original data in time domain and in frequency domain, respectively. By applying the method to analyzing the South China Sea data, the normalization data of wind speed is extracted from the sea surface temperature time series.     

块状硫化物矿石中硫化物的压溶和增生及成矿意义——以加拿大西部矿床为例

加拿大西部块状硫化物矿石普遍地发生过硫化物的压溶和增生。增生作用根据增生体的成分可以分为同质增生和异质增生，根据动力环境可以分为静态增生和动态增生。三晶嵌接结构可以是静态增生的产物。压溶和增生是块状硫化物矿床成岩和变质过程中的重要作用。脉石矿物的压溶可使原生矿石就地加富，硫化物的压溶可使成矿物质发生再活化。增生可促进矿质沉淀。富含硫化物的地层之所以能成为地球化学障而有利于后期热液叠加和层控矿床的形成，硫化物晶芽的增生是一种重要机制。     

近年来我国地震谣言的起因及对策

在充分考虑《中华人民共和国防震减实法》和《地震预报管理条例》中有关地震谣言的新规定的基础上，结合前人的工作，给出了地震谣言的新定义；对1995年12月－1999年1月期间在我国发生的31起地震谣言事件的起因和平息手段进行了研究，并对地震谣言进行了分类；将地震谣言的传播和发展过程分为三个阶段，归纳出了可以采用的地震谣言辟谣工作手段和在辟谣工作中应该注意的问题。