锡林浩特－阿巴嘎火山群内的玛珥式火山

Tephra fallout is an important type of hazard caused by explosive volcanic eruption,and numerical simulation has become a fast and effective approach to assess the dispersion and deposition of tephra fallout.According to the improved 2D diffusion model of Suzuki( 1983),we edited a tephra diffusion program that can run in the Windows system.Based on previous data,we simulated the diffusion scope of the Jinlongdingzi volcanic eruption,which is the latest eruption in the Longgang volcanic cluster.The simulated results are in good agreement with the results from measurement in situ,indicating that the model is reliable and the parameters used in the model are suitable.By using wind profiles of ten years,7,021 simulations under different wind profiles were carried out,and then probabilistic hazard maps of tephra fallout were constructed for tephra thickness thresholds,1cm and 0.5cm.This study can provide an important scientific basis for volcanic hazard analysis,risk mitigation plans and countermeasures in the Longgang volcanic area.     

南海及周围地区的现今构造运动

利用南海及其周围地区的GPS数据,分析南海及周围地区速度场和应变场的空间变化,以及相邻块体之间的相对运动.研究发现,南海现今仍在继续扩张,西部是从其北边缘向南沿NW-SE方向逐渐扩张的,东部是从中心向北与向南逐渐扩张的.由主张应变率计算的中央海盆近SN方向的平均扩张速率为3.1 mm/a.在南海东部(117.0°E),南北之间(11°～22°N)SN方向的扩张速率为9.3 mm/a,小于65Ma以来NNW-SSE方向13.0 mm/a的平均扩张速率.南海的扩张运动是印度板块、太平洋和菲律宾海板块与欧亚板块之间的相互作用,以及南海地区地幔物质上涌共同作用的结果.     

Application of stable isotope tracing technologies in identification of transformation among waters in Sanjiang Plain, Northeast China

In order to investigate the transformation among the precipitation,groundwater,and surface water in the Sanjiang Plain,Northeast China,precipitation and groundwater samples which were collected at the meteorological station of the Sanjiang Mire Wetland Experimental Station,Chinese Academy of Sciences and the surface water which collected from the Wolulan River were used to identify the transformation of three types of water.The isotope composition of different kinds of water sources were analyzed via stable isotope(deuterium and oxygen-18) investigation of natural water.The results show a clear seasonal difference in the stable isotopes in precipitation.During the cold half-year,the mean stable isotope in precipitation in the Sanjiang Plain reaches its minimum with the minimum temperature.The δ18O and δD values are high in the rainy season.In the Wolulan River,the evaporation is the highest in August and September.The volume of evaporation and the replenishment to the river is mostly same.The groundwater is recharged more by the direct infiltration of precipitation than by the river flow.The results of this study indicate that the water bodies in the Sanjiang Plain have close hydrologic relationships,and that the transformation among each water system frequently occurs.     

Elastic reverse-time migration based on amplitude-preserving P- and S-wave separation

Imaging the PP- and PS-wave for the elastic vector wave reverse-time migration requires separating the P- and S-waves during the wave field extrapolation. The amplitude and phase of the P- and S-waves are distorted when divergence and curl operators are used to separate the P- and S-waves. We present a P- and S-wave amplitude-preserving separation algorithm for the elastic wavefield extrapolation. First, we add the P-wave pressure and P-wave vibration velocity equation to the conventional elastic wave equation to decompose the P- and S-wave vectors. Then, we synthesize the scalar P- and S-wave from the vector Pand S-wave to obtain the scalar P- and S-wave. The amplitude-preserved separated P- and S-waves are imaged based on the vector wave reverse-time migration (RTM). This method ensures that the amplitude and phase of the separated P- and S-wave remain unchanged compared with the divergence and curl operators. In addition, after decomposition, the P-wave pressure and vibration velocity can be used to suppress the interlayer reflection noise and to correct the S-wave polarity. This improves the image quality of P- and S-wave in multicomponent seismic data and the true-amplitude elastic reverse time migration used in prestack inversion.     

基于TM影像的荒漠绿洲交错带土壤有机质含量反演模型

选取Landsat TM影像的光谱反射率（R）、反射率之倒数（1/R）、反射率倒数之对数（lg（1/R））、反射率一阶导数（FDR）、波段深度（D）等5种光谱指标,分别建立了奇台县土壤有机质（SOM）含量的反演模型,并利用F检验来验证模型的显著性。结果表明：用各光谱指标建立的土壤各层和不同深度SOM含量的反演模型精度值由低到高的顺序均为lg（1/R）<R<1/R<FDR<D,以D反演SOM含量的模型效果最好,且对10～20 cm的SOM含量的反演精度最高,适用于对研究区SOM含量的反演,FDR的反演效果次之,1/R和R的模型精度一般,而lg（1/R）的模型精度最差;各层拟合模型的反演精准度由低到高的顺序为50～60 cm <40～50 cm <30～40 cm <20～30 cm <0～10 cm <10～20 cm,不同深度反演模型的优劣为0～60 cm <0～50 cm <0～40 cm <0～30 cm <0～10 cm <0～20 cm。     

1011号台风“凡亚比”登陆过程数值模拟及诊断分析

利用中尺度非静力数值模式WRF V3.2.1对“凡亚比”台风(1011)的登陆过程开展了高分辨率数值模拟,模拟采用三重嵌套,最高分辨率为3 km,共积分120 h(5 d)。利用收集到的观测资料对模式模拟的结果进行了较细致的对比验证。结果表明,模式较好地模拟再现了“凡亚比”台风的发展演变以及两次登陆过程,模拟的台风路径与观测路径较为一致,模式也较好地把握住了“凡亚比”台风的强度演变过程,模拟取得了初步的成功。进一步利用高分辨率模拟资料对此次台风登陆过程的强降水开展了初步诊断分析,结果表明,在整个研究时段内,散度垂直通量绝对值的垂直积分<|Q|>与地面降水区有很好的对应,两者在空间分布和时间演变上比较一致,在降水大的区域<|Q|>的值也大,这表明<|Q|>对“凡亚比”台风强降水具有较好的诊断和指示意义。     

株洲市龙泉污水处理厂A/O生物氧化池变形监测及数据处理分析

以株洲市龙泉污水处理厂A/O生物氧化池为例介绍加载沉降监测技术方案中监测基准点、变形监测点的布设原则、方法、观测精度及周期要求,阐述引起变形点位位移中误差的主要因素,并对外业变形观测、数据处理及分析等内容进行详细的说明。     

Geochemical characteristics of hydrothermal sediments from Iheya North Knoll in the Okinawa Trough

Thirty sediment subsamples were recovered from the Iheya North hydrothermal field(with an average of 38 m away from the hydrothermal vent) in the middle Okinawa Trough.Samples were obtained by the ROV(Remote Operated Vehicle) Faxian during the virgin cruise of the R/V Kexue in 2014 with the application of push cores.The chemical compositions of the sediments show that the hydrothermal sediments near the hydrothermal vent are mainly composed of SO_3,ZnO and Fe_2O_3.Moreover,the hydrothermal sediments are also highly enriched in Pb,As,Sb,Hg,Se,Ag,Ba,Mo and Cd comparing with previous analysis results.On the other hand,the concentrations of Sr,Hg and Ag in studied sediments are strongly and positively correlated,these elements can be used as an hydrothermal indicator.In addition,a factor analysis of the sediments suggested that the sediments were mainly influenced by hydrothermal origin,and terrestrial and biogenic input are limited in studied area.It is also suggested that different stages of crystallization were involved in the formation of hydrothermal chimney from factor analysis.     

祝贺《四川气象》创刊二十周年

《四川气象》在新世纪第一个春天里迎来了她二十岁生日。在这二十年的岁月里，有许许多 多的编辑、作者为她的成长倾注了自己的心血。使她走向了成熟。二十年来，《四川气象》 已出版期刊74期，刊载学术论文等各类文章1600余篇，起到了展示气象科学研究成果，交流 气象预报、服务、管理经验，宣传气象科普知识的作用，成为了四川省气象科技人员与全国 气象工作者交流气象技术的园地，是反映四川气象科技水平和研究成果的窗口，是气象科技 人员、科技管理干部和气象爱好者的良师益友，同时它也是政府和有关部门掌握气象科技信 息，指导防灾减灾工作的有效工具。 　　随着气象事业的全面的发展，我们应当进一步解放思想，树立创新的思维，抓住机遇，不断 进取，《四川气象》也应这样，要不断创新，不断进取!要有自己的独道之处，吸引读者。 读者的需求和喜爱是《四川气象》生存和发展的必要条件。过去的一年，《四川气象》已经 作了一些重大的创新，由原来的纯学术刊物改为以刊载学术论文为主的综合性学术刊物。增 强了可读性，扩大了读者群。今后还需继续努力创新! 　　我们相信，在党的新闻政策指引下，有四川省气象局和四川省气象学会的正确领导，通过广 大科技人员和读者的积极支持和参与，《四川气象》一定会越办越好，有越来越多的读者， 成为大家喜爱的刊物，为实现四川气象事业“全国争先进，西部创一流”的目标发挥积极的 作用。 二○○一年三月八日     

青岛沧口-温泉断裂的空间展布及现代活动性研究

以野外地质观察和断裂的地质剖面为依据 ,阐述了青岛沧口 -温泉断裂的空间展布和构造特征。并应用区域地貌、地震地质、第四纪地质方法和断裂活动的绝对年龄资料对青岛沧口 -温泉断裂现代活动性进行了研究 ,认为上述断裂自晚更新世以来 ,其活动趋向稳定状态 ,属于晚第四纪不活动断裂