Adjustment of the electromagnetic field distorted by 3-D heterogeneities     

M. Menvielle  P. Tarits 《Geophysical Journal International》1994,116(3):562-570

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Existence of an Optimal Conductivity and Fréchet Differentiability In 2-D Electromagnetic Inversion     

M. E. Everett 《Geophysical Journal International》1994,117(1):111-119

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Asymptotic Theory For Diffusive Electromagnetic Imaging     

Jean Virieux  Carlos Flores-Luna  Dominique Gibert 《Geophysical Journal International》1994,119(3):857-868

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瞬变电磁法在工程地质勘察中的应用   总被引：1，自引：0，他引：1  

戴定璇  丁进  马昌今  陈道海 《物探与化探》1995,19(5):385-390

用瞬变电磁法在黄石市某矿主竖井建设地段查明了地表到地下100m的岩洞、构造破碎带、断裂带,并利用这些资料讨论了洞的成因及其与断裂破碎带的关系.圆满地完成了矿方提出的地质任务.  相似文献   

电偶源瞬变电磁测深一维全区视电阻率解释方法研究   总被引：4，自引：0，他引：4  

黄力军 《物探与化探》1995,19(5):391-397

本文从理论计算和野外实测资料处理两方面讨论了电偶源瞬变电磁测深─维全区视电阻率解释方法以及与之相关的实测数据预处理、磁场计算及─维磁场数值反演方法.  相似文献   

水平载流线圈中心点组合波频域电磁测深视电阻率定义     

苏发  何继善 《物探与化探》1995,19(5):379-384

由于近区场的复杂性及目前频域电磁测深方法的局限性,近区频域电磁测深多年来一直是地球物理领域一个悬而未决的问题.本文在近区场理论的基础上,通过引人组合波理论,提出了一种能适于近区频域电磁测深的视电阻率的定义式.该视电阻率在近区具有有效压制背景场、突出地电异常信息的功能,并能客观地反映地电断面的电性变化规律.  相似文献   

岩石摩擦-滑动中的声发射b值动态特征及其地震学意义     

曾正文  马瑾  马胜利  许秀琴 《地球物理学进展》1993,(4)

双剪试验的结果表明,岩石摩擦滑动过程中的AE b 值动态曲线可归纳为锯齿状和台柱状两类,分别对应于不规则粘滑和规则粘滑.滑动瞬间滑面上摩擦系数变化△μ的分布决定岩石的滑动方式,不均匀分布易发生不规则粘滑.均匀分布易引起规则粘滑;破裂和滑动是摩擦滑动过程中的两类AE 机制,两类AE 的能量分别与破裂面面积及△μ成正比.研究结果提示,平直光滑的地震断层可能显示出特征地震的发震特点.  相似文献   

断裂系扩展过程与地球物理场变化特征的实验研究     

张之立  李强 《地球物理学进展》1993,(4)

给出了判断断裂之间有无相互作用的力学判据.为了研究断裂间相互作用对地球物理场的影响,对若干类常见断裂系的扩展过程及扩展过程中的声发射b 值和波速变化进行了模拟实验研究.结果表明,各种断裂系由于相互作用的不同,扩展过程,声发射b 值和波速度化均有明显的不同特征.  相似文献   

磁偶源频率测深视电阻率曲线的正演计算     

郝志刚  朴化荣 《吉林大学学报(地球科学版)》1991,(1)

磁偶源频率测深法是一种有效的地球物理勘探方法。多年来,人们对这种方法的正演理论和反演解释进行了研究。文中利用快速汉克尔数值滤波算法计算了层状介质上直立磁偶极子的电磁场响应以及频率测深视电阻率的振幅响应,这种计算方法与常用的数值积分算法相比,具有计算速度快、精度高等特点。同时详细地讨论了磁偶源频率测深的特点及视电阻率理论曲线的特征。  相似文献   

Carboxylic monoacids in the air of mayombe forest (Congo): Role of the forest as a source or sink     

Jean Servant  Georges Kouadio  Bernard Cros  Robert Delmas 《Journal of Atmospheric Chemistry》1991,12(4):367-380

In the tropical rain forests of the Congo during the dry season, from June to September 1987, carboxylic acid partial pressures (P _gas) in the air above the canopy, at ground level, and at the boundary layer, were estimated from water samples such as fog and rainwater. The concentrations of these acids were also measured in the sap of tree leaves. Tree leaves act as a sink or as a source if the acid P _gas is greater of lower than the acid concentrations in molecular form in sap. For each of these soluble gases, there is a value of P _gas where the exchange is nul. This is called the compensation point. Values of the compensation point for some tree leaves were evaluated according to Henry's law. Henry's law coefficients at ppm levels were redetermined for formic (HCOOH), acetic (CH₃COOH), propionic (CH₃CH₂COOH), and isobutyric (CH₃CH(CH₃)COOH) acids.By comparison of P _gas and compensation points, it is concluded that the forest was a potential source for these acids. The soil-or the litter-acts as a significant source of a carboxylic acid of C₃ or C₄ atoms in the aliphatic chain. This carboxylic acid, not yet fully characterized, could play an important role in the rain acidity in forested zones of the equatorial areas.The direct emission of these carboxylic acids by vegetation was the main source in the boundary layer above the forest. The average emissions were 3.1×10⁹, 7.8×10⁹, and 8.4×10⁹ molecules cm^-2 s^-1 for HCOOH, CH₃COOH, and CH₃CH₂COOH, respectively. The savanna is an exogenous source of HCOOH and CH₃CH₂COOH during moderately rainy days for 30% of the time. The ozonolysis of isoprene seems to be a small source of HCOOH.  相似文献