多波多分量地震勘探资料波场分离方法研究

发布时间：2018-10-17 19:28

【摘要】：随着人们对勘探技术、成像分辨率、剖面质量要求的不断提升,近几十年以来,多波多分量勘探技术逐渐成为地震勘探的一个研究热点。它相较于常规纵波勘探,可获得更为丰富的波场信息,对地下各向异性介质的描述也更加精确,同时其技术难度和勘探成本与横波勘探相比具有一定的优势。转换波采集技术的不断成熟推动着多波多分量地震勘探技术的发展,但是多数转换波处理技术都停留在理论实验和模型试算阶段,这是由于转换波地震资料处理流程还不够完善,很多处理技术不能直接从常规纵波处理移植过来,因此,多分量资料处理技术还没有被大规模应用于生产当中。本文针对一个转换波资料处理的限制问题——P-P波与P-SV波的波场混叠,通过分析对比不同波场分离方法的分离精度、有效性以及适用范围,力求寻找出一种将P-P波与P-SV波分离的有效途径。三分量检波器的接收特性决定了单分量上的检波器除了要接收主要能量成分之外,还要接收部分其他类型的非主要能量成分的干扰波(例如垂直分量接收到的横波,水平分量接收到的纵波)。尽管我们用转换波采集技术可以获得更多的有效信息,但是由于技术的限制,沿用常规纵波处理与解释方法会损失大量的转换波有效信息,并且低速转换波信息会被误认为是“干扰波”,这使得处理结果带有很大的偏差。纵、横波具有不同的波场特征,使得它们无法在同一套处理流程中进行处理,因此,波场分离就显得尤为重要。本文对地震波的运动规律与传播特征进行了详尽的剖析,将波场分离的方法主要划分为两大类:①基于运动学特征,利用多波数据的视速度差异进行τ-p变换;②基于动力学特征,利用地震波的偏振特性的空间矢量旋转法进行极化滤波。介绍了τ-p变换法、基于坐标拉伸的τ-p变换法、协方差矩阵滤波法等。通过模型试算分析这些方法的优劣,发现单纯依赖地震波的单一特性进行分离,会受到假设条件、适用范围等因素的制约,分离效果存在一定缺陷。本文在此基础上进一步提出了一种波场分离的新方法,即将运动学特征与动力学特征相结合的基于τ-p变换域下的极化滤波波场分离方法。
[Abstract]:With the increasing requirements of exploration technology, imaging resolution and profile quality, the multi-wave and multi-component exploration technology has become a hot topic in seismic exploration in recent decades. Compared with conventional P-wave exploration, it can obtain more abundant wave field information and more accurate description of underground anisotropic media. At the same time, its technical difficulty and exploration cost have some advantages compared with S-wave exploration. The development of multi-wave and multi-component seismic exploration technology is promoted by the maturation of converted wave acquisition technology, but most of the converted wave processing techniques remain at the stage of theoretical experiment and model trial calculation. This is because the process of seismic data processing of converted wave is not perfect enough, and many processing techniques can not be directly transplanted from conventional P-wave processing. Therefore, multi-component data processing technology has not been applied in large-scale production. In this paper, aiming at a limited problem of data processing of converted wave, the aliasing of P-P wave and P-SV wave, the separation accuracy, validity and application range of different wave field separation methods are analyzed and compared. We try to find an effective way to separate P-P wave from P-SV wave. The receiving characteristics of the three-component geophone determine that the geophone on the single component must receive some other types of interference waves (such as the S-wave received by the vertical component) in addition to the main energy components. The P-wave received by the horizontal component). Although we can obtain more effective information by using the conversion wave acquisition technique, due to the limitation of the technology, the conventional P-wave processing and interpretation method will lose a large amount of converted wave effective information. And the low-speed converted wave information will be mistaken as "interference wave", which makes the processing results with a large deviation. The longitudinal and shear waves have different characteristics of wave fields, which make them unable to be processed in the same processing process. Therefore, wave field separation is particularly important. In this paper, the motion and propagation characteristics of seismic waves are analyzed in detail. The methods of wave field separation are divided into two main categories: (1) based on kinematics characteristics, 蟿 -p transform is carried out by using apparent velocity difference of multi-wave data; 2 based on the dynamic characteristics, polarization filtering is carried out by using the spatial vector rotation method of the polarization characteristics of seismic waves. 蟿 -p transformation method, 蟿 -p transformation method based on coordinate stretching, covariance matrix filtering method and so on are introduced. By analyzing the merits and demerits of these methods, it is found that only relying on the single characteristic of seismic waves for separation will be restricted by some factors, such as hypothetical conditions, applicable range, etc., and the separation effect has certain defects. In this paper, a new method of wave field separation, which combines kinematics and dynamics, is proposed, which is based on 蟿 -p transform domain.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P631.44

【相似文献】