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1.
板块内部地震的预报是一个世界性的科学难题。攻克这个难题的努力可以分成两个方面:一是以确定板块内部未来地震的地点和强度为主的长期预报研究,包括板内地震的构造环境和孕育过程的阶段性特征,大陆地区强震危险性和地震灾害的预测等。二是以确定未来地震发生时间为主的短期预报研究,包括强化地震前兆的观测以及前兆的分析和机理研究。 相似文献
2.
李淑恭 《地壳构造与地壳应力文集》2002,(1)
一、前言地震预测预报是实现减轻地震灾害的基础和关健环节。准确的短临预报直接关系到防震减灾的社会效益,而正确的中期预报是进行准确的短临预报的重要前提和背景。我国地震前兆观测手段(如大地形变、测震、地磁、地下流体、地电、重力、钻孔应力应变等)在长期的地震预测预报实践中积累了丰富的资料,并成功地预报过一些地震。但是,由于各种手段所测物理量及方法不同,使得各种手段在地震长、中、短临预测中偏重有所不同。 相似文献
3.
将数值模拟成果与监测数据集成,对三峡水库库首区诱发地震危险性进行了动态评价。在GIS (geographic information system) 平台上将数值模拟结果用专业地震模型进行评价,其成果作为评价背景数据库。用实时的地震监测数据、地下水位监测数据、地壳形变监测数据对背景数据库进行更新。选用FLAC 3D为数值模拟工具,MAPGIS为GIS基础平台,VC＋＋为开发工具,研发了水库诱发地震危险性动态评价系统。系统提供在一定蓄水位条件下、一定评价范围、一定深度内的水库诱发地震灾害危险性区划。研究结果表明,在GIS平台上,利用信息融合技术,可以将水库诱发地震的数值模拟评估、监测数据评估进行集成,实现水库诱发地震危险性动态评价。 相似文献
4.
一、引言地震的孕育是一个复杂的动力学过程,地壳介质的差异、构造间的交互作用以及观测环境等原因,导致一个地震事件往往具有不确定性。利用前兆异常来准确地预测未来地震的发生,是一个较难且较复杂的问题,而给出预报的信度和概率,正是以物理为基础的概率性预报所不可缺少的基本参数。许绍燮先生提出了用R值作为震兆信度的鉴定指标,R值为扣除了随机概率的预报成功率,后来人们均以R值来估计震兆的置信度。笔者对首都 相似文献
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6.
基于第一性原理的分子动力学计算和Rietveld技术的矿物定量计算等计算机技术的数值模拟方法是科学研究的重要手段之一,被广泛用来预测针对特定反应物的化学反应过程与结果、材料的性能改变、药物研发等.在地球科学领域中数值模拟技术也被广泛应用:地下水量、水质及污染物迁移的模拟预测、气象领域的天气和降水预报,地球层圈构造的模拟研究,成矿过程的模拟和预测等等.本综述重点回顾数值模拟技术在地球科学各领域中的应用现状,并对其应用前景进行了分析.我们建议在地球科学研究中特别是涉及"水岩"反应的实验研究中大力推广,以提高效率和做有效科学的实验,并建议利用数值模拟技术为科学解译数据提供理论支撑. 相似文献
7.
中国地壳运动观测网络在地球科学研究中的应用前景 总被引：1，自引：1，他引：1
简要地介绍了中国地壳运动观测网络的概况和目前的进展,论述了地壳运动观测网络在地球科学研究中的重要作用和应用前景。其应用潜力主要体现在:①在中国地壳运动监测研究中发挥重要作用,成为中国地震预测预报研究的重要基础;②为地球动力学研究提供重要的依据;③建立维持ITRF地球参考框架、研究地球自转、极移和章动及变化;④精化、加密全国大地网和大地水准面;⑤在气象学中的应用;⑥研究电离层电子浓度及其变化规律;⑦提供精密近实时的GPS轨道参数;⑧为广域差分定位奠定基础。 相似文献
8.
大陆动力学是地球动力学的基本组成部分,是板块构造理论的重要拓展,是固体地球科学的核心命题之一。在系统的地质、地球物理和地球化学观测的基础上,数值模拟是探讨大陆动力学过程和机制的有效手段。本文主要基于大陆动力学数值模拟,围绕大陆形成和演化过程的四个关键科学问题进行总结和探讨。(1)大陆起源与早期地球动力学演化。现今观测到的最早的大陆地壳岩石来自冥古宙,说明地球早期就已经开始大陆地壳的形成;关于当时的构造体制,存在多种不同的模式及其过渡和转换(岩浆洋、热管、滞盖等),该问题的约束甚少,是一个地球动力学的前沿科学问题。(2)大陆岩石圈的稳定性与破坏。大陆岩石圈形成之后经历几十亿年尺度的长时间演化,有些克拉通可以保持大致的稳定性直至现今,而有的克拉通却在显生宙期间经历显著的改造和破坏,无论其稳定存在还是改造破坏,都是值得深入探讨的科学问题。(3)大陆深俯冲与极限折返。超高压岩石折返代表了地球表层物质由浅入深而又由深及浅的物质循环,系统的观测和模拟对该过程和机制已有比较清晰的理解;而近年来观测到的200~350 km的超深折返岩石又提出新的挑战,其模式和机制有待进一步探索。(4)大陆碰撞造山差异性。造山带解析是大陆动力学研究的核心内容,伴随日益精细化的地学观测,也对动力学模拟提出了新的挑战,多地体的复合造山动力学值得进一步探究;同时,青藏高原作为最重要的碰撞造山带,其一级动力学驱动力仍不明确。本文在系统探讨这些科学问题的基础上,进一步提出大陆动力学数值模拟的未来研究方向:一方面是问题导向型,针对上述仍未解决的重要科学问题,尤其是一级控制机制问题,通过创新思路和精细模拟,并与观测进行系统对比分析,最终给出答案;另一方面是技术导向型,极力发展新的数值模拟方法和技术(例如双相流乃至多相流),以适应复杂地质演化中的相变、流体、熔体、地表过程等的模拟需求,这两个研究方向的发展将共同提高大陆动力学过程和机制的认知水平,促进大陆动力学理论的发展。 相似文献
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汶川、玉树大地震造成了重大人员伤亡和财产损失。地震发生后,对地观测技术成为地震灾害监测与灾情评估的重
要手段。本文将从三个方面论述对地观测技术在上述地震灾害评估和研究中所发挥的作用：一是利用高分辨率光学对地观
测技术,建立堰塞湖、道路损毁、崩塌/滑坡/碎屑流等次生地质灾害的遥感分析方法和模型,系统监测汶川地震次生地质
灾害的空间分布、损毁范围、风险程度;二是利用宽幅和干涉两种模式SAR数据,分析玉树地震的区域地质构造和岩性分
布特征,获得玉树地震同震形变场大小及其空间分布信息,证明了多模式SAR在地震灾情协同分析与评价中的有效性和重
要潜力;三是建立了地震灾害三维模拟评估系统,提高了对地震灾害三维模拟的精确性,为地震灾情的精确三维评估提供
了系统平台。 相似文献
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11.
Numerical simulation of dynamic mechanisms of the 2008 Wenchuan Ms8.0 earthquake: implications for earthquake prediction 总被引：1，自引：0，他引：1
Shoubiao Zhu 《Natural Hazards》2013,69(2):1261-1279
The sudden and unexpected Wenchuan earthquake (Ms = 8.0) occurred on the Longmen Shan Fault, causing a large number of casualties and huge property loss. Almost no definite precursors were reported prior to this event by Chinese scientists, who made a first successful prediction of the 1975 Haicheng earthquake (M = 7.3) in China. Does the unsuccessful prediction of the Wenchuan earthquake mean earthquake prediction is inherently impossible? In order to answer this question, the paper simulated inter- and co-seismic deformation, and recurrence of strong earthquakes associated with the Longmen Shan listric thrust fault by means of viscoelastic finite element method. The modeling results show that the computed interseismic strain accumulation in the lower crust beneath the Eastern Tibet is much faster than that in the other regions. In particular, the elastic strain energy density rate accumulates very rapid in and around the Longmen Shan fault in the depth above ~25 km that may explain why the great Wenchuan earthquake occurs in the region of such a slow surface deformation rate. The modeled coseismic displacements around the fault are consistent with surface rupture, aftershock distribution, and GPS measurement. Also, the model displays the slip history on the Longmen Shan fault, implying that the average earthquake recurrence interval on the Longmen Shan fault is very long, 3,300 years, which is in good agreement with the observed by paleoseismological investigations and estimates by other methods. Moreover, the model results indicate that the future earthquake could be evaluated based on numerical computation, rather than on precursors or on statistics. Numerical earthquake prediction (NEP) seems to be a promising avenue to a successful prediction, which will play an important part in natural hazard mitigation. NEP is difficult but possible, which needs well supporting. 相似文献
12.
The 10～30 days extended-range forecasting technology is a worldwide problem, but it plays a very important role in meteorological disaster prevention and mitigation decision-making services and meteorological support services for major activities in China. In the past decade, China has carried out beneficial explorations in 10-30 days extended-range forecasting theory and technology and made some progress. Based on the introduction of the theory and technology of extended-range forecast, this paper systematically introduced the technical progress of China’s extended-range forecasting service; combining with the development trend of numerical model and the demand of future extended-range forecast, here we analyzed the specific technical problems and challenges in China’s extended-range forecast service, and finally proposed the development ideas of future extended-range forecast service. 相似文献
13.
为了探索GPS和跨断层地壳形变数据联合反演效果，本文以鲜水河断裂为研究对象，利用1999~2007期，2009~2013期和2013~2017期中国大陆GPS水平速度场数据，使用贝叶斯反演方法，以跨断层数据为先验条件，估算了川滇菱形块体东边界（主要为鲜水河断裂）的断层运动速率。发现增加跨断层数据后，反演图像的近场和远场速率区别更加显著，不同期次的断层活动速率表现出明显的差异。但是，本方法在震前效果并不明显，尤其是在汶川地震前部分跨断层场地的逆向走滑特征很难表现出来，对于地震预测预报也很难起到优势作用，但从反演效果上来看，可以更直观的反映断层在近场和远场上的速率差异以及地震后断层运动速率的分段特征。最终根据上述研究方法认为鲜水河断裂带在汶川地震后，经过多年的应力调整，目前左旋走滑速率已经基本恢复到震前状态，鲜水河断裂南段持续拉张趋势，川滇菱形块体的顺时针旋转作用持续加强，鲜水河断裂的道孚段和磨西段存均在一定的走滑速率亏损，应注意这两个地区的地震危险性，以及这两个地区地震危险的关联性。 相似文献
14.
西南地区发育有我国近30%的地质灾害隐患点,是我国地质灾害成因最复杂、数量最多、灾情最严重的地区之一,为更好地了解西南地区地质灾害研究历史和防灾减灾工作,本文在系统梳理西南地区地质灾害发育分布规律及危害特征现状基础上,简要回顾了二十世纪以来西南地区地质灾害研究的主要历程,并分三个主要阶段对所取得的进展和成效进行了总结。在此基础上,对未来西南地区地质灾害的主要研究趋势进行了展望,提出了西南地区地质灾害研究应重点关注高山极高山区高位远程地质灾害识别技术、特大地质灾害链形成机理与风险防控、基于地质灾害孕灾背景大数据智能挖掘的风险动态评价等,可供西南地区地质灾害研究与防治参考。 相似文献
15.
Lightning can threaten human and equipment safety. An indicator of sever convective weather, it plays an important role in atmospheric chemistry. The intensive studies have advanced the lightning forecast in the mesoscale weather models and its application in global climate models. There are three methods to forecast lightning by using numerical weather models: Numerical diagnosis prediction based on synoptic background filed statistical relations; Flash rate parameterization developed with the relationship between dynamical, microphysical and electrification processes, and The numerical weather model coupled with the explicit electrification and lightning parameterization schemes. In this paper, the research progress in lightning forecast with three above-mentioned methods were reviewed, and the future research issues on lightning forecast were also discussed. 相似文献
16.
《Geomechanics and Geoengineering》2013,8(1):57-68
Both seismic and tsunami hazards design criteria are essential input to the rehabilitation and long-term development of city of Banda Aceh Post Sumatra 2004 (M w=9.3) disaster. A case study to develop design criteria for future disaster mitigation of the area is presented. The pilot study consists of probabilistic seismic and tsunami hazard analysis. Results of the probabilistic seismic hazard analysis indicates that peak ground acceleration at baserock for 10 and 2% probability of exceedance in 50 years is 0.3 and 0.55 g, respectively. The analysis also provides spectral values at short (T=0.2 s) and long period (T=1.0 s) motions. Some non-linear time-domain earthquake response analyses for soft, medium, and hard site-class were conducted to recommend design response spectra for each site-class. In addition, tsunami inundation maps generated from probabilistic tsunami hazard analysis were developed through tsunami wave propagation analysis and run-up numerical modeling associated with its probability of tsunamigenic earthquake source potential. Both the seismic and tsunami hazard curve and design criteria are recommended as contribution of this study for design criteria, as part of the disaster mitigation effort in the development process of the city. The methodology developed herein could be applied to other seismic and tsunami disaster potential areas. 相似文献
17.
Natural hazards in Central Java Province,Indonesia: an overview 总被引：2，自引：0，他引：2
Muh Aris Marfai Lorenz King Lalan Prasad Singh Djati Mardiatno Junun Sartohadi Danang Sri Hadmoko Anggraini Dewi 《Environmental Geology》2008,56(2):335-351
Central Java Province, Indonesia, suffers from natural hazard processes such as land subsidence, coastal inundation, flood,
volcanic eruption, earthquake, tsunami, and landslide. The occurrence of each kind of natural hazard is varied according to
the intensity of geo-processes. It is necessary to learn from the historical record of coastal inundation, flood, volcanic
eruption, earthquake, tsunami, and landslide hazards in Central Java Province to address issues of comprehensive hazard mitigation
and management action. Through the understanding about the nature and spatial distribution of natural hazards, treatments
can be done to reduce the risks. This paper presents the natural hazard phenomena in Central Java Province and provides critical
information for hazard mitigation and reduction. 相似文献
18.
地震滑坡危险性概念和基于力学模型的评估方法探讨 总被引：1，自引：0，他引：1
在我国大陆地区运用基于力学模型的Newmark位移分析方法开展地震滑坡危险性定量评估,尚处在起步阶段.为了进一步明确地震滑坡危险性概念和改进推广基于力学模型的评估方法,首先阐明了狭义的地震滑坡危险性预测评估与震后反演评估的关系; 同时为了应对地震应急、震后重建及潜在地震条件下的不同评估需求,初步提出了广义的地震滑坡危险性评估框架.随后申述了基于Newmark位移分析的地震滑坡危险性评估方法的理论基础、方法分类及最新进展,并以汶川地震滑坡危险性快速评估为例,剖析了目前影响评估有效性的不确定性及空间数据质量等问题,指出了基于力学模型的地震滑坡危险性评估方法的改进方向.建议开展潜在地震及其诱发滑坡危险性的耦合评估,建立适用于我国大陆地区地震滑坡位移分析的经验模型,以便为国家层面的地震滑坡危险性区划服务. 相似文献
19.
中国造山带动力学研究中的数值模拟应用与发展 总被引：1，自引：1，他引：0
数值模拟为造山带动力学研究提供了有效的量化工具,但即使研究人员根据造山带不同的动力问题进行针对性模拟,也很难对各种模型的优劣进行判断。文章在研究和分析国内外学者运用数值模拟研究中国造山带动力学成果的基础上,系统总结了造山带动力学数值模拟的方法及研究成果,并对未来的研究方向及趋势进行了展望。与国外造山带研究相比,中国复杂造山带的数值模拟研究仍存在不足,需要加强洋—陆俯冲模拟结果与实际地质情况的对比力度。运用多场耦合以及高精度模拟和高级求解方法相结合的数值模拟是造山带动力学模拟研究的趋势。 相似文献
20.
Statistical Analysis of Landslide Events in Central America and their Run-out Distance 总被引：3，自引：0，他引：3
Graziella Devoli Fabio V. De Blasio Anders Elverhøi Kaare Høeg 《Geotechnical and Geological Engineering》2009,27(1):23-42
Statistical analyses of landslide deposits from similar areas provide information on dynamics and rheology, and are the basis
for empirical relationships for the prediction of future events. In Central America landslides represent an important threat
in both volcanic and non-volcanic areas. Data, mainly from 348 landslides in Nicaragua, and 19 in other Central American countries
have been analyzed to describe landslide characteristics and to search for possible correlations and empirical relationships.
The mobility of a landslide, expressed as the ratio between height of fall (H) and run-out distance (L) as a function of the
volume and height of fall; and the relationship between the height of fall and run-out distance were studied for rock falls,
slides, debris flows and debris avalanches. The data show differences in run-out distance and landslide mobility among different
types of landslides and between debris flows in volcanic and non-volcanic areas. The new Central American data add to and
seem consistent with data published from other regions. Studies combining field observations and empirical relationships with
laboratory studies and numerical simulations will help in the development of more reliable empirical equations for the prediction
of landslide run-out, with applications to hazard zonation and design of optimal risk mitigation measures. 相似文献