汶川Ms8．0地震的短临地电波动（潮汐力谐振和共振波-HRT波）前兆

简要介绍了强震短临前兆的HRT波模型,和用HRT波模型分析强震前地电观测资料预测未来强震的时间、地点、震级三要素方法。用HRT波模型分析了2008年汶川MS8.0地震前四川红格地电台的记录资料,提取出了汶川MS8.0地震前短临前兆信息。     

Time-variant fragility analysis of the bridge system considering time-varying dependence among typical component seismic demands

This paper presents a copula technique to develop time-variant seismic fragility curves for corroded bridges at the system level and considers the realistic time-varying dependence among component seismic demands. Based on material deterioration mechanisms and incremental dynamic analysis, the time-evolving seismic demands of components were obtained in the form of marginal probability distributions. The time-varying dependences among bridge components were then captured with the best fitting copula function, which was selected from the commonly used copula classes by the empirical distribution based analysis method. The system time-variant fragility curves at different damage states were developed and the effects of time-varying dependences among components on the bridge system fragility were investigated. The results indicate the time-varying dependence among components significantly affects the time-variant fragility of the bridge system. The copula technique captures the nonlinear dependence among component seismic demands accurately and easily by separating the marginal distributions and the dependence among them.     

上扬子会泽地区早三叠世飞仙关组砂岩物源特征:来自重矿物铬尖晶石和碎屑锆石的限定

上扬子会泽地区早三叠世飞仙关组主要为河流相的紫红色砂岩,物源主要来自于西部和西北部。碎屑重矿物组合表明物源主要来自于岩浆岩,且重矿物中发现大量碎屑铬尖晶石和锆石。本文运用电子探针微区成分分析和碎屑锆石U-Pb测年方法,对上扬子早三叠世飞仙关组砂岩中铬尖晶石和碎屑锆石进行分析。铬尖晶石电子探针化学成分分析显示,其具有高铬、低Fe~(3+)和高TiO_2含量的特征,源岩分析指示这些铬尖晶石来源于与洋岛/板内、岛弧以及大火成岩省相关的火成岩。同时,碎屑锆石LA-ICP-MS U-Pb年龄测定表明,飞仙关组的物源主要来自于248~272Ma和715~997Ma的岩浆岩。铬尖晶石和碎屑锆石综合分析表明,248~272Ma的物源岩石具有大火成岩省玄武岩特征,主要为峨眉山玄武岩及同期基性侵入岩;715~997M的物源为洋岛/板内玄武岩类,主要为研究区周缘与新元古代苏雄组及其同期的岩浆岩;铬尖晶石指示的岛弧性质物源则可能源自1000~1100Ma的岩浆岩。同时,碎屑锆石还指示古元古代和早寒武世发育岩浆作用,且存在古老的新太古代结晶基底。这些资料为上扬子地区构造演化提供了沉积学的证据。     

敦煌造山带长山子地区变质演化及年代学研究

长山子地区位于敦煌造山带东北部,瓜州南部约100km处。该区主要出露一套中-高级变质表壳岩,主要岩石类型有长英质片麻岩、变泥质麻粒岩、高压基性麻粒岩、斜长角闪片麻岩。高压基性麻粒岩岩块、斜长角闪片麻岩岩块以构造透镜体或布丁(长度为0. 5~15m)的形式,被夹持于长英质片麻岩、变泥质麻粒岩组成的基质之中,呈现典型"基质夹岩块"的混杂带特征。高压基性麻粒岩、斜长角闪片麻岩、泥质麻粒岩中,普遍保留了二至三个阶段的变质矿物组合。进变质阶段矿物组合(M1)为石榴子石变斑晶中的细小矿物包裹体,变质高峰期矿物组合(M2)为石榴子石变斑晶和基质矿物,退变质阶段矿物组合(M3)主要为围绕石榴子石变斑晶边部发育的"白眼圈"状后成合晶。本区各类变质岩石均记录了顺时针型变质作用P-T轨迹,系典型俯冲-碰撞造山带变质作用特征。退变质阶段P-T轨迹属于西阿尔卑斯型,说明变质岩折返速率较快。变质高峰期(M2)属于中压变质相系,P-T条件分别为790~870℃/1.29~1.37GPa(高压基性麻粒岩)、680~685℃/0.89~0.97GPa(斜长角闪片麻岩)、860~880℃/0.90~1.14GPa(变泥质麻粒岩),它们之间存在大的差异。这说明,它们是形成于同一俯冲隧道内不同深度的变质岩石,在构造折返阶段才混杂在一起形成构造混杂岩。二次离子质谱(SIMS)锆石U-Pb定年表明,长山子地区变质杂岩记录了早泥盆世的俯冲事件(419~417Ma)。     

云南省地震前兆模拟观测数据库的建设与实现

地震前兆现象的分析研究是开展地震预测的重要途径.在地震预测尚处于经验性预报的现阶段,积累可靠的前兆数据尤为重要.虽然我国的前兆台网观测技术已基本进入数字化发展阶段,但大量的模拟观测仍在运行,几十年来积累的模拟观测数据仍是十分宝贵的科研资料.如何对已有的模拟数据进行科学管理、使未来采集的模拟数据与已有数据进行科学的衔接、为分析预报提供方便快捷的数据服务、使前兆模拟数据的产出和使用真正实现网络数据库的管理等都是值得深入思考并认真解决的重要问题.     

Numerical Simulations of Intense Meiyu Rainfall in 1991 over the Changjiang and Huaihe River Valleys by a Regional Climate Model with p-σ Incorporated Coordinate System

1.IntroductionAlthoughGCMsprovedsuccessfulinreproducingthebasicfeaturesoflarge--scaleatmosphericcirculations(Gates,1992),theyaretoocoarsetodescribethedetailsofregionalclimatepatterns(Grotch,etal.,1991).Intheregionswheretheatmosphericdynamicalandphysicalforcingsvaryonascaleoflessthanafewhundredkilometers,suchasinthepresenceofcomplexterrain,afactorof10orgreaterincreaseinmodelhorizontalresolutionmayberequiredtosimulatetherealisticregionalresponsestothefutureclimatechanges.Duetothelimitationsinb…     

基于TIGGE数据的我国寒潮自动识别预报方法

利用1951—2006年中央气象台寒潮天气过程数据以及NCEP/NCAR 500 hPa高度场等逐日再分析资料,通过客观聚类方法与主观对比分析确定寒潮爆发的典型形势场,结合寒潮过程特征量阈值,建立了基于TIGGE集合预报产品的寒潮自动识别客观预报方法,并利用TIGGE集合预报数据对2008年1月和2009年1月两次寒潮天气过程进行预报试验。结果表明:利用500 hPa高度距平场进行聚类分析,一方面可以消除环流季节特征对划分结果的影响,另一方面也突出了寒潮这种强天气的异常扰动表现;基于集合预报产品的寒潮自动识别预报方法浓缩了集合预报产品信息,可直接为预报员提供寒潮发生的概率预报,从而在集合预报产品与我国实际灾害性天气之间建立了直接联系。     

大庆地震台网近震震级偏差分析与校正

选取大庆地震台网2002-2009年近震报告资料,以《黑龙江省地震目录》给出的震级为标准,进行震级偏差统计.按地区分段校正后,震级精度明显提高.     

Mesoscale numerical simulation study of warm fog dissipation by salt particles seeding

Based on the dynamic framework of WRF and Morrison 2-moment explicit cloud scheme, a salt-seeding scheme was developed and used to simulate the dissipation of a warm fog event during 6–7 November 2009 in the Beijing and Tianjin area. The seeding effect and its physical mechanism were studied. The results indicate that when seeding fog with salt particles sized 80 μm and at a quantity of 6 gm~(-2) at the fog top, the seeding effect near the ground surface layer is negative in the beginning period, and then a positive seeding effect begins to appear at 18 min, with the best effect appearing at 21 min after seeding operation. The positive effect can last about 35 min. The microphysical mechanism of the warm fog dissipation is because of the evaporation due to the water vapor condensation on the salt particles and coalescence with salt particles.The process of fog water coalescence with salt particles contributed mostly to this warm fog dissipation. Furthermore, two series of sensitivity experiments were performed to study the seeding effect under different seeding amounts and salt particles sizes. The results show that seeding fog with salt particles sized of 80 μm can have the best seeding effect, and the seeding effect is negative when the salt particle size is less than 10 μm. For salt particles sized 80 μm, the best seeding effect, with corresponding visibility of 380 m, can be achieved when the seeding amount is 30 g m~(-2).     

《江苏省地图集》电子版的设计与实现

探讨地图集电子版的设计原则,从《江苏省地图集》电子版的设计与实现入手,分析地图集电子版的设计思路和技术方案.阐述多媒体电子地图集的解决方案.