中国大陆地震灾害时空分布特征及地形影响因素分析

基于1990—2020年地震灾害损失(包括经济损失、人员死亡和人员受伤)数据,分析了过去30年中国大陆地区地震灾害损失的时空分布特征。采用常规标准化方法分析了1990—2019年我国大陆地区地震灾害经济损失的时间分布,认为地震灾害在过去30年间逐渐由人身安全威胁向经济财产威胁转变。通过整理分析2011—2020年各省地震灾害的空间分布特征,认为有必要进一步强化四川、云南、甘肃的抗震设防工作,提升其抵御灾害地震风险的能力;在中东部经济较发达地区,应尤其关注地震造成的间接经济损失和人员受伤情况。通过各省的提取地形坡度因素,采用地统计方法定量计算地震损失与地形坡度因素间的空间相关性系数,认为在以自然条件为基础分析地震灾害的过程中,因震致死与地形的空间相关性不如经济损失和因震致伤高,结合过去30年地震灾害的时间分布特征,得出因震致死和因震致伤总体保持平稳,但经济损失急剧增长,且增长趋势越来越显著,这主要是由经济发展等社会人文因素导致。     

Influences of sea ice on eastern Bering Sea phytoplankton

The influence of sea ice on the species composition and cell density of phytoplankton was investigated in the eastern Bering Sea in spring 2008. Diatoms,particularly pennate diatoms,dominated the phytoplankton community. The dominant species were G rammonema islandica(Grunow in Van Heurck) Hasle,Fragilariopsis cylindrus(Grunow) Krieger,F. oceanica(Cleve) Hasle,Navicula vanhoeffenii Gran,Thalassiosira antarctica Comber,T. gravida Cleve,T. nordenskieldii Cleve,and T. rotula Meunier. Phytoplankton cell densities varied from 0.08×104 to 428.8×104 cells/L,with an average of 30.3×104 cells/L. Using cluster analysis,phytoplankton were grouped into three assemblages defined by ice-forming conditions: open water,ice edge,and sea ice assemblages. In spring,when the sea ice melts,the phytoplankton dispersed from the sea ice to the ice edge and even into open waters. Thus,these phytoplankton in the sea ice may serve as a "seed bank" for phytoplankton population succession in the subarctic ecosystem. Moreover,historical studies combined with these results suggest that the sizes of diatom species have become smaller,shifting from microplankton to nannoplankton-dominated communities.     

Low elevation of the northern Lhasa terrane in the Eocene: Implications for relief development in south Tibet

The uplift history of Tibet is crucial for understanding the geodynamic and palaeoclimatologic evolution of Asia; however, the pattern of plateau uplift through space and time remains unresolved. We use stable isotope data from palaeosol carbonates to reconstruct the Eocene (~46 Ma) elevation of the Tangra Yum Co region (northern Lhasa terrane). The difference between the oxygen isotopic compositions of the studied palaeosols and Eocene surface water near the source of the Indian monsoon indicates a palaeoelevation of 2590 (+730/?910) m for Tangra Yum Co (present altitude: ~4600 m). A similar palaeoaltitude is obtained by comparing our data with modern soils and taking past environmental changes into account. Combining our results with published palaeoelevation estimates for Tibet suggests significant relief (~2 km) during the Eocene, when a low‐lying basin in the northern Lhasa terrane was bounded by the Qiangtang and Gangdese mountain belts to the north and south respectively.     

西沙地区晚中新世以来碳酸盐岩的沉积演化及储层特征

生物礁滩相碳酸盐岩是南海海域深水区重要的油气储层之一.通过对西科1井(0~576.5 m)岩心的宏观描述及微观分析, 结合古生物、古地磁、高分辨岩心扫描及大量分析测试结果, 对碳酸盐岩-生物礁滩体系展开了精细研究.研究表明: 该井晚中新世以来记录了6次暴露事件、2次淹没事件, 结合古生物、古地磁、Li同位素分析, 可划分为8个三级层序, 其中晚中新世黄流组和第四系乐东组为主要成礁期.通过细致的岩相学研究, 系统刻画了生物礁-碳酸盐岩的岩石类型、成岩作用类型和孔隙类型, 重建了成岩环境.      

南海西北部琼东南盆地深水沉积环境演化及其油气勘探意义

Over the past several years, a number of hydrocarbon reservoirs have been discovered in the deepwater area of Qiongdongnan Basin, northwestern South China Sea. These oil/gas fields demonstrate that the...     

基于探空云识别方法的云垂直结构分布特征

云的垂直结构特征作为云重要的宏观特征之一,直接决定了云的类型,进而通过发射和吸收辐射的方式影响着地气系统的能量收支平衡,因此对云垂直结构特征的研究一直都是云物理研究的一个重要方向。作为观测云垂直结构特征的一种方式,探空气球通过获取沿路径方向高分辨率的廓线信息,采用一定反演方法从而能够较为准确的识别云的垂直结构。本文即利用我国业务布网探空站的观测资料,采用相对湿度阈值法识别云垂直结构,并同激光云高仪、“风云四号”静止卫星和毫米波云雷达对识别的云结构特征量进行了一致性检验。在此基础上,统计分析了2015～2017年单层、两层和三层云的垂直结构分布特征、日变化和季节变化特征以及全国区域分布特征,结果表明:（1）整体分布上,单层云在垂直方向上出现的高度范围介于多层云的高度范围内,并且随着云层数的增加,云在垂直方向上更为伸展,即高层云越高,低层云越低;（2）在日变化中,中午单层和多层云中最低层云的云底高度均高于早晨,而夜间单层和多层云中最高层云的云顶高度则高于早晨和中午,同时中间层云厚的变化要小于最上层和最下层云厚的变化;（3）在季节变化中,夏季云量较其他季节更多,云体发展也更为深厚,表明温暖的大气条件更有利于云的形成和发展;（4）我国云垂直结构分布特征具有明显的纬向变化趋势,从以青藏高原为中心的西南地区的云底较高云体较薄的云,逐步过渡到以东南沿海地区为中心的云底较低云体较为深厚的云,表明不同地形和气候带的差异与不同云类型的分布直接相关。     

2021年5月22日青海玛多MS 7.4地震灾害损失快速评估分析

2021年5月22日青海玛多M_S 7.4地震表现为灾情重、伤亡轻的特点,采用极震区烈度估计、烈度衰减关系、人员伤亡评估3种烈度衰减模型进行灾害损失快速评估,与地震现场调查结果进行对比,可知对于此次玛多M_S 7.4地震,3种模型评估与地震现场调查结果存在偏差,认为主要由地震影响场分布、人口分布、房屋建筑（抗震能力）、地形地貌、次生灾害等因素不同所致。结果显示,通过提高地震影响场评估的精准性及人口分布、房屋建筑等数据空间分布的准确性和后期专家干预等措施,均可有效提升地震灾害损失快速评估精准性。     

2021年国外地震灾害及损失述评

通过多种渠道收集并整理2021年全球地震灾情信息,对比分析国外历年地震灾害情况,根据2021年度国外重大地震灾害事件,总结其灾害特点,可知2021年国外地震灾害程度与前2年相比有所加重,地震灾害相对集中,灾区房屋抗震性能差与次生灾害重是导致人员伤亡的重要原因。     

GIS与GPS在矿石码头调度中的应用

随着社会经济的迅猛发展,我国对于钢铁的需求量日益增加,铁矿石进口量急剧增加。在码头规模不扩张的情况下,如何提高码头的运营效率以适应当今矿石进口量的增长是管理者急需解决的问题。本文在C++语言环境下,应用Map Info公司的Map X开发组件、GPS的卫星定位功能及GPRS的数据传输功能,开发出矿石码头调度系统。该系统利用中控室中的码头调度管理平台与车辆上移动站分系统的交互,实现了中控室中实时可视化监控车辆位置、不同状态车辆显示、垛位状态监控、向车辆终端快速准确送达调度指令,以及码头中控室与车辆间的快速交互。本系统完成了码头设施的实时监控、动态调配及最大化利用,从而在码头规模不变的情况下大幅度提高了运营效率。     

Protoraphis Simonsen,a newly recorded marine epizoic diatom genus for China

Epizoic diatoms on marine copepods are common in nature and may have a special ecological relationship with their hosts.However,this special ecological group is not well known,and it has only rarely been studied in the China seas.To address this knowledge gap,the species diversity and classification of epizoic diatoms on planktonic copepods were studied with samples collected from the East China Sea.In the present study,a marine araphid diatom genus Protoraphis and its type species,Pr.hustedtiana,were observed and identified by light and electron microscopy,thus representing the first record of this genus and its type species in China.This genus is characterized by a median sternum strongly bent to opposite sides and terminate in two transapical grooves at the valve ends.Protoraphis hustedtiana was found to be epizoic on the posterior body appendages and segments of the marine calanoid copepod Candacia bradyi.An internal view shows a complex,ear-shaped process that is close to the apical slit field.The ecological habitats and geographical distributions of Protoraphis were also discussed,and,together with complementary morphological studies,our results have increased the number of records for marine epizoic diatoms to three genera with three species in China,including Pseudohimantidium and Pseudofalcula.