地面电法在巴林左旗扶贫凿井工程中的应用     

高文明  许海  赵宝忠  刘全国  于洋 《城市地质》2016,(3):79-82

巴林左旗是我国水资源严重缺乏的地区之一。本文介绍了利用地面电法,在巴林左旗扶贫凿井工作中确定井位。扶贫工作组首先在测区进行水文地质踏勘,并向当地群众了解一些凿井情况,运用水文地质方法分析初步适宜凿井的地点,再布置地面电法工作,进而依据测深曲线的解释资料确定井位,最后通过实际凿井工作来对物探工作加以验证。工作过程中,灵活运用水文、地质理论知识,通过实践,丰富了找水经验,强化了理论知识的掌握。  相似文献   

Mechanics of seismic instabilities induced by the recovery of hydrocarbons     

J. -R. Grasso 《Pure and Applied Geophysics》1992,139(3-4):507-534

We review earthquake distributions associated with hydrocarbon fields in the context of pore pressure diffusion models, poroelastic stress transfer and isostasy theory. These three mechanisms trigger or induce seismic instabilities at both local scale (D5 km) and at regional scale (D20 km). The modeled changes in stress are small (1 MPa), whatever the tectonic setting. Each mechanism corresponds to different production processes. (1) Local hydraulic fracturing due to fluid injection induces seismic-slip on cracks (M _L3) within the injected reservoir through decreasing the effective stress. (2) Pure fluid withdrawal causes pore pressure to decrease within the reservoir. It triggers adjustments of the geological structure to perturbations related to the reservoir response to depletion. Poroelastic mechanisms transfer this stress change from the reservoir to the surrounding levels whereM _L5 seismic instabilities occur either above or below the reservoir. (3) Massive hydrocarbon recovery induces crustal readjustments due to the removal of load from the upper crust. It can induce larger earthquakes (M _L6) at greater distance from the hydrocarbon fields than the two other mechanisms.Due to the mechanical properties of the shallow rock matrices involved, seismic slip triggered either by mechanism (1) or (2), is a second-order process of the main elastoplastic deformation. for a minimum of 80% of commercially productive basins, most of the local deformation is reported as aseismic, i.e., there is no evidence forM _L3 earthquakes. Nevertheless, the induced stresses vary as a function of time in a manner that depends on the hydraulic diffusivity (i.e., permeability) of the reservoir and surrounding rocks. Because small earthquakes (M _L3) indicate changes in stress and pore pressure, monitoring of seismicity is a means of assessingin situ reservoir behavior.The less constrained seismic response to hydrocarbon recovery is the possible connection between local fluid manipulations, triggered earthquakes and major regional earthquakes. Positive feedback mechanisms suggest that the region of seismic hazard changes is much larger than the area where hydrocarbons are extracted. These observations and models testify that fluid movement and pore pressure changes (increase or decrease) play important roles in the mechanics of earthquakes and in the triggering of natural earthquakes.  相似文献   

Magnetic Field Vector Retrieval With the Helioseismic and Magnetic Imager     

J. M. Borrero  S. Tomczyk  A. Norton  T. Darnell  J. Schou  P. Scherrer  R. Bush  Y. Liu 《Solar physics》2007,240(1):177-196

We investigate the accuracy to which we can retrieve the solar photospheric magnetic field vector using the Helioseismic and Magnetic Imager (HMI) that will fly onboard of the Solar Dynamics Observatory by inverting simulated HMI profiles. The simulated profiles realistically take into account the effects of the photon noise, limited spectral resolution, instrumental polarization modulation, solar p modes, and temporal averaging. The accuracy of the determination of the magnetic field vector is studied by considering the different operational modes of the instrument.  相似文献   

2013年1月华北灰霾气溶胶光学特性的垂直分布     

孙强  范学花  李艳伟 《遥感学报》2015,19(3):520-529

利用Cloud-Aerosol Li DAR with Orthogonal Polarization(CALIOP)正交极化云—气溶胶激光雷达资料、Aerosol Robotic Network(AERONET)气溶胶观测资料、地面常规气象观测资料和Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)模式分析了2013年1月份华北地区的3次中重度灰霾天气过程,着重对灰霾天气过程中大气气溶胶的衰减后向散射系数、退偏比和色比等光学参数的垂直分布进行了研究。结果表明,2013年1月份华北地区灰霾天气发生时,低层大气(2 km)以下污染最严重,存在大量的气溶胶粒子。1月29日重度灰霾时气溶胶的后向散射系数增大至0.0045 km-1·sr-1,退偏比大于20%,0—8 km高度范围内的色比值大于100%的比例约为36.3%;气溶胶光学厚度从0.2增大至2.1,Angstrom指数由1.4降至0.9,表明气溶胶光学厚度增加的同时,大气中混合的粗粒子气溶胶比重增加。HYSPLIT后向轨迹模拟结果显示:500 m、1000 m和1500 m 3个高度的气流均途经蒙古国、中国内蒙古自治区、西北地区,最后影响华北地区,表明这次灰霾污染事件除受本地排放的气溶胶粒子影响,还受到源于蒙古国、内蒙古、中国西北部地区远程输送的沙尘影响。  相似文献   

Polarization of Microwave Radio Emission of Flare-Producing Solar Active Regions     

Vladimir M. Bogod  Leonid V. Yasnov 《Solar physics》2009,255(2):253-271

On the basis of our multiwavelength observations made with the one-dimensional RATAN-600 radio telescope, we study the inversion of the circular polarization in the solar microwave emission at different frequencies. The inversion is detected in the emission of flare-producing active regions (FPARs) at various stages of their development, starting from the pre-flare stage. During the latest 23rd solar cycle maximum, numerous FPARs revealed spectral inhomogeneities in their polarized microwave radiation (Bogod and Tokhchukova, 2003, Astron. Lett. 29, 263). Here, we discuss a particular case of such inhomogeneities, the frequency-dependent double inversion of the sign of circular polarization, which probably reflects some essential processes in FPARs. We consider several mechanisms for the double inversion: linear interaction of waves in the region of a quasitransverse magnetic field, the propagation of waves through a region of zero magnetic field, the scattering of radio waves on waves of high-frequency plasma turbulence, the influence of the current fibrils on the propagation of the radio emission, and the magnetic “dips,” in which the direction of magnetic field lines changes the sign relative to the observer. All of them have shortcomings, but the last mechanism explains the observations the best.  相似文献   

A polarized microwave radiative transfer model for passive remote sensing   总被引：1，自引：0，他引：1  

M. Deiveegan  C. Balaji  S.P. Venkateshan 《Atmospheric Research》2008,88(3-4):277-293

The objective of the present work is to develop a general purpose, polarized, microwave radiative transfer forward model, including calculation of interaction parameters for fast, simultaneous and accurate generation of radiances, for use in a wide variety of atmospheric retrieval applications. This complete polarized model includes the generation of atmospheric profiles, calculation of the interaction parameters and the solution of the vector radiative transfer equations. In the present work, the doubling and adding method is used to calculate radiances. Mie theory is used for spherical particles to evaluate the polarized scattering matrix. Two types of sea surface models applicable for specular and diffuse surfaces respectively are implemented. The model has been validated against standard benchmark cases and experimental data available in literature. While the model is itself generic, parametric studies are performed to study the influence of the vertical structure of the atmosphere, for two polarizations and a set of frequencies to be used on the microwave imager aboard the proposed Indo-French climate research satellite MEGHA-TROPIQUES.  相似文献   

地面高精度磁测在印尼滨海型磁铁矿应用     

胡维竹  杨茂齐 《云南地质》2010,29(2):197-200

综合运用低纬度化极与建立模型正演等数据处理手段进行隐伏矿体预测,发现与成矿有关的磁异常,显示良好成矿前景。钻孔证实有工业矿体。  相似文献   

太阳Stokes光谱望远镜的结构及其数据处理方法     

梁红飞  苏同卫  赵海娟 《天文研究与技术》2007,4(3):249-257

云南天文台的太阳Stokes光谱望远镜是一台通过测量磁敏谱线的Stokes参数I,Q,U和V的轮廓来研究太阳磁场精细结构的光谱型矢量磁场测量仪。它利用4个完整的Stokes轮廓所蕴含的丰富信息,完全确定辐射的偏振状态,从而精确地测定太阳黑子区的矢量磁场。文章首先介绍了该望远镜的结构,进而详细地介绍了该望远镜所测量的偏振光谱资料的处理方法。  相似文献   

水库诱发地震机制研究   总被引：3，自引：0，他引：3  

梁青槐  高士钧 《华南地震》1995,15(1):74-77

根据摩尔－库仑破裂准则，利用库区应力摩尔圆的移动和半径的变化以及岩石破裂线的变动，分析了库区不同区域的诱震机制，指出水库诱发地震易发生在断裂带及其附近，断层穿过库心正下方时大大增加诱震的危险性；分级蓄水则可以减小诱发快速响应型地震的可能性。  相似文献   

诱发地震与诱发性前兆     

毛可  郭大庆  张树勋  孙景芳  郭文娣 《高原地震》1995,(2)

本文以１９６９年以来中国大陆９对ＭＳ≥５．９级地震为例，引出诱发性前兆的概念。诱发性前兆是指远区强震（Ａ）发生后３个月内产生于未来后续地震（Ｂ）附近（△≤２００ｋｍ）的，并与该地震有某种成因联系的继发性异常和新异常。诱发地震与诱发性前兆是反映强震间耦合作用的同因异象。１９８８年以来南北带强震组（１９８８年耿马、澜沧７．６级地震──１９９０年天祝、景泰６．２级地震）诱发地震和诱发性前兆显著，并呈连锁式分布，表明该地震组各强震之间具有较强的耦合作用。  相似文献