地震波震源加载方式对波场特征的影响

目的地震波场数值模拟中,研究胀缩源、集中力源、剪切源在各向异性介质中引起的波场特征。方法采用MPML吸收边界,详细地分析了3种震源的加载机理,基于交错网格高阶有限差分法的波动方程进行数值模拟。结果不同震源在介质中对波场类型、偏振方向、各分量的能量分配等特征有较大的影响。结论结果对横波分裂的研究和野外观测系统的震源研究有一定的理论指导意义。     

横波在各向异性复合介质中的传播

横波在各向异性介质中传播时将发生横波的分裂。把玻璃和水泥组成的复合介质看做是对裂缝简单而合理的近似,对裂缝引起的各向异性介质中横波的分裂进行了较详细的观察,当横波沿着平行于层面的方向传播时,可以观察到明显的横波分裂。裂缝引起的各向异性与裂缝参数和声源之间有密切的关系。在一定范围内,介质的横波速度各向异性程度随裂缝密度及裂缝宽度的增加而变大,且较高频率的探头对介质的各向异性更敏感。     

横波在各向异性复合介质中的传播

横波在各向异性介质中传播时将发生横波的分裂。把玻璃和水泥组成的复合介质看做是对裂缝简单而合理的近似,对裂缝引起的各向异性介质中横波的分裂进行了较详细的观察,当横波沿着平行于层面的方向传播时,可以观察到明显的横波分裂。裂缝引起的各向异性与裂缝参数和声源之间有密切的关系。在一定范围内,介质的横波速度各向异性程度随裂缝密度及裂缝宽度的增加而变大。且较高频率的探头对介质的各向异性更敏感。     

垂直地震剖面横波分裂的理论研究

地下岩石中普遍存在着由地应力诱导排列的垂直裂隙或裂缝，地震横波通过这样的介质传播时，会发生横波分裂。文中首先推导了含裂隙介质中零井源距垂直地震剖面记录的解析表达式，然后就不同方位裂隙组成的多层介质使用的伪谱法模拟了二分量横波全裂的ＶＳＰ记录，最后利用ＶＳＰ记录的解析式分析了ＶＳＰ记录中的横波分裂。     

基于黏弹各向异性理论的地震波场数值模拟与分析

基于Carcione黏弹各向异性理论及具有任意倾斜对称轴的横向各向同性介质(TTI)的本构关系,利用二维三分量高阶交错网格有限差分和完全匹配层边界条件对黏弹TTI介质的地震波场信息进行了数值模拟。研究发现:1改变黏弹TTI介质的弹性参数,对地震波传播造成显著影响。其中,C_(13)主要控制qS1波中质点的偏振方向,进而影响了qS1波波形和反射同相轴的形态;而C_(66)则主要控制qS2波中质点的偏振方向,从而影响了qS2波波形和反射同相轴的形态;2利用层状黏弹TTI介质进行数值模拟,可以很好地观察到拟横波在遇到反射界面时发生的横波再分裂现象;同时由于介质黏弹性的存在,导致地震波出现显著的衰减。这将为进一步研究各向异性介质中复杂的波场信息提供帮助。     

旋转交错网格在横波分裂和再分裂模拟与分析中的应用

横波分裂可以用来探测地下介质的方位各向异性特征,如地幔流动方向、地壳内断层和应力的方向,以及近地表裂缝发育方位等,在地球深部结构探测和油气田勘探中具有重要作用。由于地下一般存在多层方位各向异性介质,记录的横波可能发生过多次分裂,因此,采用正演方法对横波分裂和再分裂进行数值模拟与分析,对于横波分裂反演和地下横向结构探测具有重要意义。旋转交错网格由于将速度和应力的不同分量置于同一网格点,可以避免各向异性参数的插值,正演更为精确。因此,采用旋转交错网格对方位倾斜横向各向同性介质的一阶速度-应力方程差分离散,并构造完全匹配层边界,实现了多层方位各向异性介质多分量逆VSP资料的正演;然后以此为基础,分析了横波发生分裂和再分裂时分裂参数随方位变化的规律;最后采用层剥离策略对多层方位各向异性进行反演和补偿,并探讨了层剥离方法的应用条件和技巧。     

基于横波分裂的地层裂缝预测方法与应用

多波资料比单波资料含有更丰富的地层信息，特别是利用横波在裂缝介质中的分裂机制分离出的快，慢横波，可进行地下地层的各向异性研究，获取地层裂缝信息，预测出地层裂缝系统的发育方向和发育程度，有助于裂缝性油气藏的研究，作者研究了一套利用多波资料预测地层裂缝的方法，并得到了有效的应用。     

三维双相各向异性介质弹性波方程交错网格高阶有限差分法模拟

基于Biot理论,给出了三维双相各向异性介质应力-速度弹性波方程交错网格任意偶阶精度有限差分解法,并对三维双相各向异性(TIH)介质中弹性波场进行了模拟.结果表明,弹性波在三维双相各向异性介质中传播时存在快纵波qP1、快横波qS1、慢横波qS2和慢纵波qP2,并清楚地观测到了横波分裂、横波分裂盲点、波面三分叉等特殊现象.快纵波在固相和流相中的相位相同;而慢纵波在固相和流相中的相位相反,即慢纵波在流相中振幅大,而在固相中的振幅较小.另外,三维双相各向异性介质中弹性波场的快纵波和快横波的耦合关系、波的类型、能量分布和相位等都是在三维空间中变化的.     

含裂隙介质中横波分裂现象的数值模拟

波动方程高阶差分法具有精度高、数值频散小的优点,使用这种高阶差分解法,对裂隙介质中的弹性波的传播进行了模拟,对其中的横波分裂现象进行了分析研究,结果发现,在裂隙介质中,横波分裂后快横波与慢横波的能量分布与裂隙和测线的夹角有关;慢横波的能量衰减快;快、慢横波遇到反射界面时会产生各自的反射波、透射波和转换波、使记录复杂化,模拟结果对裂隙发育地区的地震资料的采集,处理和解释具有指导意义。     

三维双相各向异性介质弹性波方程交错网格高阶有限差分法模拟

基于Biot理论，给出了三维双相各向异性介质应力一速度弹性波方程交错网格任意偶阶精度有限差分解法，并对三维双相各向异性（TIH）介质中弹性波场进行了模拟。结果表明，弹性波在三维双相各向异性介质中传播时存在快纵波qP1、快横波qS1、慢横波qS2和慢纵波qP2，并清楚地观测到。T横波分裂、横波分裂盲点、波面三分叉等特殊现象。快纵波在固相和流相中的相位相同；而慢纵波在固相和流相中的相位相反，即慢纵波在流相中振幅大，而在固相中的振幅较小。另外，三维双相各向异性介质中弹性波场的快纵波和快横波的耦合关系、波的类型、能量分布和相位等都是在三维空间中变化的。     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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-