基于二维高密度电阻率勘探数据的三维反演及应用

针对目前高密度电阻率法所采用的数据处理方法主要是把地质结构体视为二度体进行二维处理,从而二维数据资料处理结果只是一种近似解释,其计算精度与反演效果达不到精确反演的要求,设计一种典型的地质体模型,利用有限单元法进行正演计算,对含有高斯随机误差的各测线二维正演数据分别进行高密度电阻率法二维、三维反演,对比二维和三维的反演结果.最后在广东某场地采用高密度电阻率法对岩层划分,利用二维勘探的数据进行二、三维反演.研究结果表明:三维反演受高斯随机误差的影响更小,反演结果与实际地质模型更接近;三维反演在岩层划分中更能凸显岩层分界面区域,岩层的空间分布及岩层、覆盖层的整体连续性能更真实地体现,与钻探结果吻合程度更好.     

基于卷积神经网络的大地电磁反演

为了提高大地电磁二维反演精度,提出一种基于卷积神经网络的大地电磁反演方法。具体实现步骤如下:首先,对不同模型进行二维正演构建样本数据集;其次,将视电阻率和相位数据作为双通道网络输入,与其对应的地电模型参数作为输出搭建卷积神经网络框架,并对该网络进行监督学习与调参,从而获取最佳反演网络排列及超参数;最后,利用已训练好的网络对未知地电模型进行反演。通过理论模型检验的方法探讨大地电磁TM模式下多种地电模型体的卷积神经网络反演成像效果,并讨论输入分量和模型体深度对反演效果的影响。研究结果表明:本文提出的反演方法能对地电模型实现精准定位与成像,"聚焦"效果比最小二乘反演的优;同时,视电阻率和相位联合反演结果优于单一参量反演结果,浅部模型体的反演结果比深部模型体的优,并且联合反演的均方误差是单一反演的30%～50%。实测结果验证了所提出方法的有效性。     

大地电磁主轴各向异性二维理论模型反演分析

地下介质普遍存在各向异性,为反应地下真实地质情况,需建立各向异性模型进行研究。本文主要进行主轴各向异性大地电磁二维反演研究,采用有限单元法作为正演模拟方法,将正演响应结果与前人计算结果进行对比分析,验证了算法的正确性,并对不同方向上电阻率响应灵敏度进行分析。采用非线性共轭梯度法进行反演研究,该方法不需要直接计算雅克比矩阵,相对于其他反演方法节省了计算时间,计算效率高;目标函数的建立对于不同方向上的电阻率采用不同的正则化参数来进行约束。通过复杂的各向异性体模型进行反演,结果显示对于不同方向上电阻率的恢复以及异常体位置的圈定都取得了较好的效果,说明了反演算法的有效性。     

深层砂泥岩薄互层的地震识别方法

深层砂泥岩薄互层油气藏是一类典型的低孔、低渗型油气藏,储层一般具有埋藏深、横向变化快、深层物性差的特点。利用常规的薄层定量描述方法只能识别地层厚度不小于λ／4的孤立薄层,很难实现精细解释。为此,采用正-反演联合预测技术,通过建立符合地下实际情况的的地球物理模型,从正演角度分析目的层的地震波场特征;同时对正演结果进行模型反演,定量分析反演砂体的横向及纵向展布特征。结果表明这种基于模型正演的地震识别方法既能够发挥地震资料在地层横向展布上的优势,又能够提高纵向上的解释精度,为识别前梨园地区深层砂、泥岩互层结构的隐蔽性储层提供参考。     

浅层岩溶和采空区综合探测方法与模型试验

岩溶和采空区已经成为高速公路建设中面临的热点、难点问题。为了准确探测高速公路地基下伏岩层中岩溶和采空区的几何形态和空间分布,提出了地质雷达先验信息的高密度电阻率约束反演方法。采用常规高密度电阻率反演方法、地质雷达和携带先验信息的高密度电阻率约束反演方法,对常见的岩溶和采空区地电模型进行数值模拟,分析岩溶和采空区不同方法的成像规律。结果表明,与常规高密度电阻率反演和地质雷达正演结果相比,携带先验信息约束的高密度电阻率法反演的异常体的空间形态更接近于真实地电模型,对边界的识别更加准确。随后,通过对山东章丘地区岩溶和采空区的模型试验,探明了岩溶和采空区的分布情况,验证了该综合预报方法对岩溶和采空区的探测效果,为高速公路地基下岩溶和采空区的治理方案提供了依据。     

高密度电法在水利水电工程地质勘察中的应用

本文以广东省东莞市某水库工程的大坝防渗隐患勘测和整治为研究对象,采用有限元分析法对大坝渗透通道异常进行正反演分析,并对实际的大坝隐患目标体运用高密度电法数据采集和分析。结果表明,在正演结果分析中,坝体的视电阻率与模型相比存在较好的分层现象,由于渗透通道的异常存在,坝体浸润区的视电阻率存在封闭的低阻,且向两边有一定的延伸;在反演结果分析中,反演的低阻封闭体的范围明显缩小,异常体的视电阻率值可以恢复为5Ω·m左右。在浸润区的基岩范围内,受到上部渗透通道异常体低阻的多次“映射”影响,导致下部的视电阻率率值出现畸变;在坝体背水面共布置3条测线探明了大坝坝址隐伏渗透通道的走向、埋深和空间分布,为水利水电工程坝体的防渗治理提供翔实的地质资料。     

基于高密度电法的城市内河挡墙埋深探测

基于内河挡墙与下层原状土之间电阻率差异,以有限差分法为理论依据,应用高密度电法数值模拟软件RES2DMOD建立挡墙模型进行正演,并利用软件RES2DINV进行反演,研究温纳、偶极、微分三种装置类型的视电阻率正、反演结果分布特征,结合南京某内河工程挡墙实例,探讨所采用方法的精确性.研究结果表明:三种装置的理论模型正反演结果均能有效反映挡墙下底界面的起伏形态,不同装置对不同方向反应的灵敏度不同,温纳和微分装置对电阻率的垂向分辨率比较高,偶极装置对水平向变化具有较高的灵敏度;南京内河工程挡墙工程实例表明:当接地条件良好时,采用温纳装置能够获得较好的效果,这与正演成果是一致的.经后期开挖验证,反演结果相对误差一般小于20 cm,最大百分比误差绝对值小于8%,达到探测的精度要求,这为城市内河河道的整治提供了依据.     

交互初至波检测与表层模型正反演

初至波表层速度模型层析反演是层析静校正的重要基础。作者研究了一套完整的方法和软件系统 ,利用计算机可视化技术进行人机交互初至波检测、表层模型正演及反演 ,可直观地分析、监控初至波检测的合理性及模型层析反演的质量 ,提高表层速度模型层析反演的可靠性 ,为层析静校正提供合理的表层速度模型。     

基于有限单元法的三维地电断面电阻率反演

在三维电阻率的有限单元正演模拟中,简化边界条件以减少计算时间,推导了用异常电位法计算偏导数矩阵的方法,克服了总电位法中的电源点附近节点电位模拟误差的影响,使偏导数计算精度大幅度提高;在最小二乘反演中,加入体积因子以解决多解性问题,并提高了反演精度;通过对典型模型的试算,反演结果与真实模型较吻合.     

基于支持向量机改进的克里金插值法—以汾渭平原PM2.5数据为例

克里金插值法根据待测点与已知点的空间位置关系以及研究区域内变量的空间相关性为已知点赋予不同权重,再通过加权求和的方式得到待测点的估计值,为待测点提供最佳的线性无偏估计。变异函数描述了区域化变量的空间变化信息,常用的理论变异函数包括球状模型、指数模型和高斯模型,然而以上模型形式较为固定且选择较为主观,可能无法准确反映数据波动趋势。基于此,提出引入支持向量机作为新的变异函数对克里金方法进行改进。使用汾渭平原PM2.5浓度数据对改进前后的克里金插值法进行效果对比,结果发现：①支持向量机能够拟合出变异函数的变化趋势,②改进后的克里金插值精度优于改进前的克里金插值精度,因此支持向量机改进的克里金插值法是一种可选的克里金方法。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that