内蒙古地震预警基准台网监控能力评估     

郝美仙  王鑫  张建中 《地震地磁观测与研究》2017,39(1):85-88

国家地震烈度速报与预警工程项目已启动,内蒙古自治区地震局已完成预警基准台站勘选工作。利用近震计算公式,利用已选定台址与现有台站噪声水平,评估内蒙古自治区预警基准站建成后地震监控能力。结果表明,呼和浩特、包头、鄂尔多斯和乌兰察布市地区,地震监测能力在1.0级,而赤峰—通辽地区监测能力将达0.5级。  相似文献   

河南及邻区瑞利波群速度噪声层析成像     

邢康  贾漯昭 《中国地震》2019,35(4):685-694

本文选取河南及邻区39个宽频带和甚宽频带地震台站记录的2014年1月～2015年12月垂直分量的连续波形资料,通过波形互相关和叠加运算得到台站间的经验格林函数,并用时频分析方法提取了498条瑞利波群速度频散曲线,进而采用噪声层析成像方法反演获得了河南及邻区8～25s的瑞利波群速度分布图像。结果表明,8s周期的群速度分布与地表构造特征密切相关,平原地区表现为低速异常,而基岩出露的山区呈现为高速异常;14s、20s周期的群速度在山区表现的高速异常与8s相似,说明中上地壳与地壳浅部结构有一定的相关性和继承性;8～20s周期的群速度在华北平原地区存在低速异常范围随周期增加而减小的现象。华北平原地区在下地壳表现出的低速异常,可能与大陆地壳减薄有关。大致以太行-武陵重力梯度带为界,下地壳表现出的西部低速、东部至研究区中部高速异常差异,体现了地壳东薄西厚的结构特征。  相似文献   

Assessing flood risk in Baiyangdian Lake area in a changing climate using an integrated hydrological-hydrodynamic modelling     

Y. Wang  X. Zhang  M. Mu  C. Zhang  A. Lv 《水文科学杂志》2019,64(16):2006-2014

ABSTRACT

Flood-risk is affected by both climatic and anthropogenic factors. In this study, we assess changes in flood risk induced by a combination of climate change and flood prevention sets in the Baiyangdian (BYD) Lake area of China. Extreme storm events are analysed by the bias-corrected climate data from global climate models. A hydrological model is implemented and integrated with a hydrodynamic model to assess flood risk under three scenarios. The streamflow into the BYD was validated against historical flash-flood events. The results indicate that the changing climate increased extreme precipitation, upstream total inflow and the flood risk at the core region of Xiong’an New Area (XNA), the newly announced special economic zone in the BYD area. However, flood prevention measures can effectively mitigate the climatic effect. The research highlights the severe flash-flood risk at BYD and demonstrates the urgent need for a climate-resilient plan for XNA.  相似文献   

Features of internal tides observed near the shelf break in the northern South China Sea     

Chen  Shengli  Chen  Daoyi  Xing  Jiuxing  Hu  Jianyu  Sun  Zhenyu 《Ocean Dynamics》2019,69(3):353-365

Ocean Dynamics - Features of internal tides in the northern South China Sea are investigated using measurements of two moorings at 506 m (MR1) and 260 m (MR2) working between...  相似文献   

云南地震重点监视防御区民众地震科普认知分析     

吕佳丽  张方浩  李兆隆  邓树荣  曹彦波 《震灾防御技术》2019,14(4):869-881

云南地处云贵高原,地震活动频繁,是一个多震多灾的省份。当地民众对地震灾害的认知程度和自救互救能力,对于保护生命财产安全,减轻地震灾害损失,显得尤为重要。本文选取云南地震重点监视防御区为样本区域,对民众的地震科普知识认知情况和互联网信息智慧化推送接受程度等进行了调研。根据调查结果分析评价,10个样本区域民众的地震科普知识整体认知水平不高,“优秀”等级的州市为0,“良好”等级的州市有6个,“差”的州市有4个;对互联网智慧化推送的民众接受程度存在比较明显的群体差异。  相似文献   

The first ground tooth artifact in Upper Palaeolithic China     

Yue ZHANG  Shuangquan ZHANG  Xing GAO  Fuyou CHEN 《中国科学:地球科学(英文版)》2019,(2)

Scholars have long recognized the importance of organic artifacts to an improved understanding of the economic and social behavior of Palaeolithic hominins. However, in contrast to archaeological studies in other parts of the world, osseous industries from China have received only limited attention. As one of the first steps aiming at tipping this balance, the current paper examines, therefore, a shaped boar tusk—one particular element of hunter-gatherers' tool kit at Shuidonggou Locality 12 (SDG12). Morphological and metrical comparisons of the tusk with both paleontological specimens and bone artifacts from the same site demonstrate that wear pattern on one of the dentin surfaces of the tooth is not significant different from occlusal attritions in living animals, while linear striations on the other dentin facet are most probably artificial grinding marks formed by prehistoric toolmakers in attempts to manufacture a scraper. The tusk specimen from SDG12 represents the first evidence of a ground tooth in Upper Palaeolithic China. The current study indicates that hominins in Shuidonggou area had achieved a deepened understanding of physical properties of osseous material available in environs and ultimately broadened their range of raw material selection by adding a particular element to the inventory of subsistence tools.  相似文献   

气枪信号触发台站的自动快速识别          下载免费PDF全文

黄艳丹  李军  金星  邱毅  林彬华 《地震工程学报》2017,39(2):234-239

气枪震源是高度可重复的人工震源,在深部探测工作中应用广泛。以福建省地震局组织开展的水库气枪实验为研究对象,面向未来技术的发展,提出基于气枪激发波形的相关性计算,自动获取气枪信号触发台站情况,并绘制触发台站的分布图。对处理结果分析认为:该方法能快速准确识别触发台站,可迅速作出分布图,直观地反应气枪激发效果,较好地为实验现场实验条件的调整提供依据。  相似文献   

深水牵引流沉积的研究历程、现状与前景   总被引：8，自引：0，他引：8  

高振中  何幼斌  刘成鑫  邢凤存  王昌勇 《古地理学报》2006,8(3):331-338

深水牵引流沉积研究,是沉积学研究中一个较新的领域。在这个领域中,我国学者做出了应有的贡献,并且具有自己的特色和优势。目前研究的深水牵引流沉积,一是等深流沉积,二是内波、内潮汐沉积。等深流沉积研究开始于20世纪60年代,早期主要是对小规模的细粒薄层等深流沉积的研究,而现在已发展到对大规模等深流沉积体--等深岩丘的研究。内波内潮汐沉积研究始于20世纪90年代,也是从小规模内波、内潮汐沉积的鉴别开始,现在已达到研究深海大型沉积物波的阶段。今后等深流沉积研究的主攻方向,应是地层记录中的等深岩丘,并特别注意碎屑岩等深岩丘的发现和研究。内波、内潮汐沉积方面,最有矿产意义的当属由大型沉积物波构建的地质体。而首例地层记录中的大型沉积物波,已在塔里木盆地中部奥陶系中被鉴别出来,并具有含油气远景。从目前对内波、内潮汐的研究势头来看,我国很有希望在该领域继续保持国际领先地位。  相似文献   

Effect of source parameters on forward-directivity velocity pulse for vertical strike slip fault in half space   总被引：1，自引：0，他引：1  

刘启方  袁一凡  金星 《地震工程与工程振动(英文版)》2006,5(1):1-9

It has been found that the large velocity pulse is one of the most important characteristics of near-fault strong ground motions. Some statistical relationships between pulse period and the moment magnitude for near-fault strong ground motions have been established by Somerville （1998）; Alavi and Krawinkler （2000）; and Mavroeidis and Papageorgiou （2003）, where no variety of rupture velocity, fault depth, and fault distance, etc. were considered. Since near-fault ground motions are significantly influenced by the rupture process and source parameters, the effects of some source parameters on the amplitude and the period ofa forward-directivity velocity pulse in a half space are analyzed by the finite difference method combined with the kinematic source model in this paper. The study shows that the rupture velocity, fault depth, position of the initial rupture point and distribution of asperities are the most important parameters to the velocity pulse. Generally, the pulse period decreases and the pulse amplitude increases as the rupture velocity increases for shallow crustal earthquakes. In a definite region besides the fault trace, the pulse period increases as the fault depth increases. For a uniform strike slip fault, rupture initiating from one end of a fault and propagating to the other always generates a higher pulse amplitude and longer pulse period than in other cases.  相似文献   

长周期地震动三维有限元数值模拟方法   总被引：1，自引：0，他引：1  

丁海平  刘启方  金星 《地震工程与工程振动》2006,26(5):27-31

采用数值方法对长周期地震动进行模拟已成为当前强地面运动预测的研究方向之一。本文提出了一种有限元并行计算的高效地震动数值模拟方法,可以同时考虑震源、传播途径和场地条件对地震动的影响,并根据昆明地区未来可能发生的设定地震对昆明市的影响地震动进行了预测。这一方法可以应用于国内已探测的发震活断层进行地震危害性评价工作。  相似文献