地震监测设施与观测环境保护工作探讨

在对地震监测设施及观测环境保护工作现状进行概述后，分析提出了加强地震监测设施及观测环境保护工作的措施和建议。     

谈地震监测设施和观测环境的保护

对山西长治地区地震监测设施和观测环境保护的现状、地震监测设施及观测环境遭受破坏和干扰的主要原因进行了分析,并结合工作实际提出了一些工作对策和建议.认为,应从加强县级地震机构建设,合理规划地震监测台网等方面入手,加强对地震监测设施及观测环境的保护.     

20起地震监测设施和观测环境保护行政执法案例特征分析

运用法学原理,结合地震监测设施和观测环境保护法律、法规,对《地震行政执法案例选编》中提供的20起地震监测设施和观测环境保护行政执法案例进行了综合统计分析,探讨了实际工作中涉及到的若干法律问题。     

浅谈地震台站监测设施和观测环境保护

分析了地震台站监测设施和观测环境受干扰与影响的主要因素,总结了近年来地震台站监测设施和观测环境保护的经验启示,并就进一步做好地震监测设施和观测环境保护工作提出相关建议。     

高速公路建设危害地震监测设施和观测环境行政执法中存在的问题及对策

随着我国经济的飞速发展,高速公路建设越来越多,地震监测设施和观测环境因其建设被危害的现象越来越严重。地震监测设施和观测环境保护行政执法的目的是保证地震监测设施完好、排除地震监测设施正常效能范围内的干扰源,保障地震监测预报工作质量。这类行政执法实际上是跨学科的,不仅要熟悉防震减灾法律法规,还需要了解测震、电磁、地壳形变和地下流体观测的地震专业知识。本文列举甘肃省办理过的3起典型案件,剖析该类案件行政执法各阶段的工作重点,提出高速公路建设危害地震监测设施和观测环境行政执法中存在法律依据缺位、执法主动性不够、执法效率低下、相关宣传不够的现实问题,通过分析、论证,给出有效建议。      

攀枝花市地震监测设施和观测环境保护的实践与探索

本文简要介绍了攀枝花市地质背景和地震台站概况,对地震监测设施和观测环境遭受干扰、破坏情况进行了分析,总结了地震观测环境保护的方法措施。阐述了经济社会发展与地震监测之间的关系,对新时期如何做好地震观测环境保护工作提出了建议和对策。     

高台地震台依法保护地震监测环境的经验

阐述了高台地震台观测环境现状,通过高台地震台监测环境保护实践活动,认识到：法律、法规是地震监测环境得到有利保护的重要保障;观测环境保护工作需要依靠当地政府及各部门的重视和支持;地震台站工作人员要加强法律、法规的学习和运用,担负起地震台站监测环境保护的任务。     

合理保护地震台站观测环境和监测设施

地震台站监测环境的好坏,直接影响地震监测工作质量,因此,依法保护地震台站观测环境和监测设施意义重大。通过对近年来省内几起典型的地震监测设施和地震观测环境破坏事件进行分析,发现问题,总结经验,探讨解决办法,为进一步做好地震观测环境和监测设施的保护工作提供建议和意见。     

山西地区地震形变观测调研

形变观测是地球物理观测的重要手段之一,以能够清楚地观测地球固体潮汐为发展目标,对地震监测预报具有重要作用。为进一步加强山西省地震监测及预测预报工作,全面了解和掌握1985年以来山西省形变观测资料的变化,探讨形变台网观测资料在监测预报中发挥的重要作用,系统梳理山西地区形变观测资料变化,对山西省历史及目前运行的形变学科仪器、数量等进行全面摸排,为该区形变观测工作提供参考。结果表明,山西形变观测已有一定规模,并具有以下特征：(1)观测仪器设备种类多,监测手段全,但仪器标准化程度不高;(2)观测资料具有一定的映震能力;(3)观测环境较复杂,应进一步做好观测环境保护。     

蒙城地震台观测环境保护案例分析及思考

简要介绍了蒙城地震台自1992年以来发生的观测环境保护案例,分析了台站观测环境保护工作的重点和难点,深入探讨了新时期地震台站观测环境保护的特点及其引发的思考。     

Temporal variations and scaling of streamflow and baseflow and their nitrate-nitrogen concentrations and loads

The patterns of temporal variations of precipitation (P), streamflow (SF) and baseflow (BF) as well as their nitrate-nitrogen (nitrate) concentrations (C) and loads (L) from a long-term record (28 years) in the Raccoon River, Iowa, were analyzed using variogram and spectral analyses. The daily P is random but scaling may exist in the daily SF and BF with a possible break point in the scaling at about 18 days and 45 days, respectively. The nitrate concentrations and loads are shown to have a half-year cycle while daily P, SF, and BF have a one-year cycle. Furthermore, there may be a low-frequency cycle of 6–8 years in C. The power spectra of C and L in both SF and BF exhibit fractal 1/f scaling with two characteristic frequencies of half-year and one-year, and are fitted well with the spectrum of the gamma distribution. The nitrate input to SF and BF at the Raccoon watershed seems likely to be a white noise process superimposed on another process with a half-year and one-year cycle.     

燕郊等测点迁移优化与地磁观测研究

为优化地磁观测条件，开展了燕郊、夏垫等测点迁移工作；按照测眯迁移原则与实施技术方案，完整地收集并整理了地质构造与地球物理等方面的基本资料；进行了野外实地勘察，磁场梯度的测量，确定了新测点，在新老测点上进行了较长时间的地磁场对比观测；应用多种方法分析研究了地磁对比观测资料，结果表明，新老测点与有关测点的地磁变化具有良好的一致性，并得到了新老测点之间的地磁数据的按点差。     

东、南洞庭湖的径流、泥沙特征及冲淤规律

通过实地调查并对1957年以来水文、泥沙观测资料做系统分析和计算,探讨东、南洞庭湖出、入湖水量、沙量的年际和年内变化特征,以及长江下荆江段裁弯对湖区径流和泥沙的影响。提出了湖区泥沙汛淤枯冲的变化规律及水位升降与湖区泥沙冲淤的关系;论证了丰、平、枯年湖区淤积严重,面积日益缩小对径流的调节作用正在减弱。     

GIS与防灾减灾

地理信息系统(GIS)在我国已得到广泛的应用。在简要介绍G1S的发展历程、特点和发展趋势的基础上，重点从防灾减灾的角度介绍了GIS在气象灾害、地震灾害、地质灾害等领域的应用成果。     

Seismics and optics: hyperbolae and curvatures

We rederive and generalize hyperbolic moveout formulae for the common-midpoint (CMP) gather and for the zero-offset (ZO) section that can be efficiently used for macro-model-independent reflection imaging in two-dimensional media. The hyperbolic moveout formulae for the common-midpoint gather are obtained from different Taylor series expansions of a particular parametric moveout surface defined in the multicoverage data space. Such a moveout surface involves three kinematic wave-field attributes of two hypothetical waves, which have to be determined by a coherency analysis. By using hyperbolic moveout curves in the CMP gather and in the ZO section one can determine these attributes in two steps. The relationships between the local shapes of the interfaces and the attributes of the hypothetical wave-fields attributes are considered by means of geometrical optics. The determination of these attributes allows to perform a macro-model-independent ZO simulation and a subsequent inversion.     

Assessing Groundwater Depletion and Dynamics Using GRACE and InSAR: Potential and Limitations

In the last decade, remote sensing of the temporal variation of ground level and gravity has improved our understanding of groundwater dynamics and storage. Mass changes are measured by GRACE (Gravity Recovery and Climate Experiment) satellites, whereas ground deformation is measured by processing synthetic aperture radar satellites data using the InSAR (Interferometry of Synthetic Aperture Radar) techniques. Both methods are complementary and offer different sensitivities to aquifer system processes. GRACE is sensitive to mass changes over large spatial scales (more than 100,000 km²). As such, it fails in providing groundwater storage change estimates at local or regional scales relevant to most aquifer systems, and at which most groundwater management schemes are applied. However, InSAR measures ground displacement due to aquifer response to fluid‐pressure changes. InSAR applications to groundwater depletion assessments are limited to aquifer systems susceptible to measurable deformation. Furthermore, the inversion of InSAR‐derived displacement maps into volume of depleted groundwater storage (both reversible and largely irreversible) is confounded by vertical and horizontal variability of sediment compressibility. During the last decade, both techniques have shown increasing interest in the scientific community to complement available in situ observations where they are insufficient. In this review, we present the theoretical and conceptual bases of each method, and present idealized scenarios to highlight the potential benefits and challenges of combining these techniques to remotely assess groundwater storage changes and other aspects of the dynamics of aquifer systems.     

Correlation of foreshocks and aftershocks and asperities

A close correlation in spatial distribution of local seismic activity and energy release patterns before and after the 1979 Petatlan, Mexico earthquake suggests heterogeneity within the fault plane of this major low-angle thrust event associated with subduction along the Middle America Trench. A simple two-asperity model is proposed to account for the complexity. Foreshocks and aftershocks of the neighboring 1981 Playa Azul earthquake showed a similar pattern. As both events occurred at the junction of the Orozco Fracture Zone and the Middle America Trench, we speculate that the observed complex fault plane is caused by subduction of the rugged ocean floor of the Orozco Fracture Zone. Short-term precursory seismicity prior to the Petatlan earthquake can be explained by using the asperity model and migration of a slip front from the south-east to the north-west across the main shock source region.