汕头试验井地面与井下环境地噪声对比测试分析     

郭德顺  陈建涛  谢剑波  叶春明 《华南地震》2014,(3):57-64

试验井位于汕头市衡山路,观测系统为井下宽频地震计TBG-60B和地面宽频带地震计TDV-60B,频带为60S~50 Hz,选取的地面观测数据与对应的井下观测数据都是同一时间的,使用童汪练研究员的地噪声分析软件和MATLAB绘图工具,研究台站环境地噪声随观测井深度的变化特征,得到井深与观测地噪声之间的对比关系,为井下地震台站勘选和工程建设提供基础数据。发现地噪声水平从覆盖层进入到基岩有很大变化,从强风化层进入到中微风化层也有明显变化,考虑钻井建设成本和台站建设地噪声水平要求之间的综合效益,在粤东地区典型的地质结构条件,较佳的平衡点应该是至少需要进入完整中微风化层基岩10 m。  相似文献   

南海北部新生界地层的远偏移距折射波速度特征     

陈江欣  张宝金  宋海斌 《地球物理学报》2014,57(7):2223-2234

南海北部为张裂大陆边缘，在新生代时期经历了复杂的地质演化，具有良好油气勘探前景.本文首次利用南海北部某区域长排列地震数据的远偏移距折射波速度计算方法获得南海北部地层层速度，并进行了分析，此外，还提出了非初至折射波的概念.本方法在共偏移距剖面上识别、拾取折射波层位，得到折射波走时的横向连续变化数据，利用不同共偏移距同一折射波层位的到达时差计算该折射层位的速度结构.该方法在南海北部陆坡某区域地震资料的应用，揭示了新生界地层层速度的整体结构，反映了新生代不同时代地层的速度变化特征，为进一步利用折射层速度资料探讨南海新生代地质演化提供了新的视角.研究表明，与常规初至折射波法相比，远偏移距折射波能够提供更多的地质信息;该方法的初步应用能够对远偏移距折射波的研究提供进一步的视角.  相似文献   

The Jurassic Coast Story Book: An approach to geoheritage interpretation from the Jurassic Coast World Heritage Site     

Sam Scriven 《Proceedings of the Geologists' Association. Geologists' Association》2019,130(3-4):493-506

The World Heritage status of the Jurassic Coast has important implications for how the geoheritage of the site is communicated to audiences. UNESCO defines World Heritage Sites as places with Outstanding Universal Value to all people that must be preserved for future generations. Building relationships between people and place is key to conservation and on the Jurassic Coast that is delivered by providing audiences with physical, intellectual and emotional access to the Site. Heritage interpretation offers an effective way to develop these connections and create diverse ways for people to engage with the unique Earth Science stories that underpin the World Heritage Status of the Dorset and East Devon Coast. This paper reflects on the approach to interpretation taken by the Jurassic Coast Team and explores the ways in which geoheritage is a challenging subject to interpret. Practitioners on the Jurassic Coast have more recently developed an interpretive approach to help overcome these difficulties. Three categories of geoheritage stories were identified (Landscape, Cultural geology and Earth History) and three interpretive principles were devised (perspective, intimacy and imagination) as a way of scoping out a relevant emotional context for interpretive content. This approach laid the foundation for the development of a new interpretation framework for the Jurassic Coast – The Jurassic Coast Story Book, which will be subject to ongoing testing and evaluation by the new organisation leading on the protection and promotion of the Jurassic Coast World Heritage Site; Jurassic Coast Trust.  相似文献   

GridGIS若干关键技术研究     

吴明光  谢耕  原传刚 《测绘科学技术学报》2006,23(6):415-417,421

分析了当前地理信息系统运用和功能现状,提出了网格地理信息系统的4点技术特征,并在此基础上提出了一种以服务为中心的体系结构.针对面向对象空间数据模型无法描述许多广泛存在却无法用属性、方法和事件来描述的地理逻辑,以及空间数据语意不一致带来的数据集成和综合应用问题,提出了一种基于规则的空间数据组织模式.针对网格环境下空间信息的深度共享问题,提出了一种结合Multi-Agents和Web Services这两种分布式计算技术的空间信息服务模式.  相似文献   

Potentially harmful World Bank projects are proximate to areas of biodiversity conservation importance     

《Global Environmental Change》2021

For many countries in the global south the World Bank is a key funder of development. A subset of the activities it funds have the potential to cause harm to biodiversity. Currently, however, little is known about the spatial coincidence of Bank-funded projects and important areas for biodiversity. Using a dataset of World Bank projects funded between 1995 and 2014, we examine the relationship between potentially harmful project activities and the ranges of globally threatened birds, mammals, and amphibians, Key Biodiversity Areas, protected areas, and biodiversity hotspots. We find that 5 by 5 km cells containing a project activity are more likely to contain a Key Biodiversity Area, or a biodiversity hotspot, and have on average greater richness of globally threatened species, than those without. This relationship was statistically significant even after considering human population and country-level socio-economic effects except in the case of Key Biodiversity Areas. We also found limited evidence that activities are systematically placed within countries to avoid the ranges of threatened species or Key Biodiversity Areas. By contrast, we found a negative relationship between project activities and protected areas globally and within most countries, which may be evidence that potentially harmful activities are placed to avoid protected areas. Our findings raise questions about whether the Banks environmental safeguards have adequately translated into avoidance of highly diverse areas. Given the size of the World Bank’s lending portfolio and its role in setting industry best practice our results are concerning for conservation efforts.  相似文献   

甘南州国土空间规划辅助决策系统的构建与实现          下载免费PDF全文

王金媛  张晖 《甘肃地质》2022,(2):77-81

基于“天地图·甘肃”地理信息公共服务平台提供的地图API功能,在 “天地图·甘南”州级节点的基础上,整合甘南州国土空间规划相关数据和评价模型,采用可视化B／S前后端分离架构,矢量瓦片索引和微服务等技术,搭建了甘南州国土空间规划辅助决策系统,并通过系统平台实现了资源浏览、数据查询、数据统计、占地分析、规划冲突分析、数据大屏等辅助决策功能,为建设项目选址、用地审批、规划审查、土地储备与开发等提供决策服务。  相似文献   

Bragg reflection of water waves by multiple floating horizontal flexible membranes with submerged rectangular bars on the seabed     

《Applied Ocean Research》2019

Bragg reflection of water waves by multiple floating horizontal flexible membranes is investigated based on the linear wave theory and the assumption of small membrane response. Under the floating horizontal membranes, periodical submerged rectangular bars are arranged on the flat seabed. The total reflection and transmission coefficients are obtained by using the eigenfunction expansion method and the wide spacing approximation. The calculated coefficients are validated with the results available in the literature, which shows that the present method is applicable. The characteristics of Bragg reflection are systematically investigated by changing various parameters including the height of the rectangular bars, the number, the tension, the spacing, and the length of the flexible membranes. The results can help designing multiple floating horizontal flexible membranes as effective floating breakwaters by taking advantage of Bragg reflection.  相似文献   

基于Django框架的两种Web地震目录分页方法     

马士振  林向东  白永福  张红旗  冯刚 《地震地磁观测与研究》2015,(1)

在搭建基于Django框架的地震目录服务系统过程中,为实现地震目录的快速展示,介绍了在Web服务层和数据库服务层进行数据分页的方法,并实测了两者的Web响应速度。结果表明:当数据量较大时,在数据库服务层实现分页的效率更高。  相似文献   

接地导线源电磁场全域有效趋肤深度   总被引：3，自引：2，他引：1       下载免费PDF全文

陈卫营  薛国强 《地球物理学报》2014,57(7):2314-2320

为了更好地推进广域电磁法的发展和应用，本文以接地长导线源为例，研究了可控源电磁场全场域的有效趋肤深度.利用频域电偶极源在均匀半空间产生电磁场的闭合表达式，计算了不同电磁场分量定义的有效趋肤深度，并讨论了在不同频率、不同偏移距、不同电导率情况下，有效趋肤深度的变化特性.根据有效趋肤深度随偏移距的变化特征以及与平面波趋肤深度之间的关系，利用多项式拟合的办法在五个不同频率范围内给出了适用于全场域的有效趋肤深度快速估算公式.研究结果表明：不同分量定义的有效趋肤深度是不同的，但是它们随偏移距、频率、电导率等参数的变化趋势是类似的，而且在一定范围内都趋近于平面波趋肤深度.理论模型的研究表明，有效趋肤深度可以作为测量参数选取和数据解释工作的参考依据.  相似文献   

宽频带超导重力仪的研制进展          下载免费PDF全文

刘习凯  马东  陈亮  刘向东 《地球物理学报》2018,61(7):3037-3043

本文报道一种构建宽频带高分辨率超导重力仪（SG）的方法.与已商业化的GWR超导重力仪类似，新型超导重力仪同样使用磁悬浮超导检验质量来构建弹簧振子结构，不同的是弹簧振子的固有频率更高，可以有效覆盖地脉动频带.同时，利用基于超导量子干涉器件（SQUID）的位移传感技术，大幅提高了位移传感灵敏度，以保证仪器在测量带宽扩展之后仍具有与GWR仪器相当的测量分辨率，从而实现对时变重力信号与地球背景噪声信号的同时高分辨观测.宽频带超导重力仪核心部件垂向超导加速度计（VSA）的设计、组装和初步测试已经完成.结果表明，加速度计的噪声本底为8 μGal/Hz^1/2@0.1 Hz，实现了对地脉动信号的高分辨率测量.而为了将仪器噪声本底降低到GWR仪器水平，加速度计的固有频率需要进一步减小，该部分参数优化工作正在进行.本文将对垂向超导加速度计的工作原理、结构和测试结果进行详细介绍.  相似文献