吉林省松江河新生代火山岩覆盖区反射地震探测资料处理研究

发布时间：2018-01-02 23:06

本文关键词：吉林省松江河新生代火山岩覆盖区反射地震探测资料处理研究　出处：《中国地质大学(北京)》2016年硕士论文　论文类型：学位论文

【摘要】：火山岩发育较强区可以形成多种的金属、非金属矿藏,在对这类工区进行勘探时,地震勘探发挥了其固有的优势。主要优势表现为勘探范围大、勘探深度大,以及获得信息上在空间上具有较好的连续性。然而,火山岩覆盖区会产生火山喷发、变质作用、侵入作用,并且,构造发育、岩性变化大、地表情况复杂,决定了火山岩地震勘探存在诸多难点。首先,地表特征方面,本工区地表部分地段高差大,加之沿测线浅表存在腐殖质、沼泽等,地表激发、接收条件的高度不一致性,导致静校正问题比较突出。其次,地表条件和激发因素的不同,再加上中深部复杂的断层及其衍生的复杂断裂系统,造成地震资料的干扰波特征(频率、视速度等)变化大,某些干扰(如面波、多次折射、环境噪音等)与有效波难以区分,会给去噪工作造成较大困难。同时,地表特征的复杂性使相邻炮集间、炮集内各道和不同时间的接收信号在能量、频率、相位等方面存在差异显著,造成子波差别较大,地震子波经过大地滤波器后,改变了原来的相位特征,同时频率变低,其地层分辨率也降低。因此,火山岩覆盖区的地震勘探存在诸多问题。本文分析了工区地震资料的特点和其处理的难点。对不同的处理难点,采用了相应的处理方法。在静校正方面试验层析静校正的速度模型的精确度和校正效果;在去噪方面,首先针对工区地表变化剧烈的特点,分段分析单炮中干扰波的特征,针对该段干扰波的特征采取相应的处理参数,并采用多种去噪技术相结合的去噪方法,试验其对多种干扰波的压制效果;在反褶积方面,采用地表一致性反褶积方法,验证其在压缩子波、消除地表因素对振幅和子波的影响、提高分辨率上的效果。通过以上处理方法的应用,得到了该工区地震资料处理的适用的处理方法。表明层析静校正可以得到比较精确的浅层速度模型,并且取得良好的静校正效果;采用多种去噪技术相结合的去噪方法可以较好的压制多种干扰波,地表一致性反褶积可以较好的压缩子波、消除由地表因素对振幅和子波的影响、提高分辨率。最后,通过对地震剖面与单炮分段的对比,验证了处理结果的可靠性。这对火山岩覆盖区地震勘探数据的处理工作具有指导性的意义。
[Abstract]:Many kinds of metal and nonmetallic deposits can be formed in the area with strong volcanic rock development. Seismic exploration has played its inherent advantage in the exploration of this kind of work area. The main advantages are that the exploration scope is large and the exploration depth is large. However, volcanic eruptions, metamorphism, intrusions, tectonic development, great lithologic changes and complex surface conditions occur in volcanic rock overlying areas. It is determined that there are many difficulties in seismic exploration of volcanic rocks. Firstly, in terms of surface characteristics, there is a great difference in height in some parts of the surface of the work area, in addition, humus, swamp and so on exist along the survey line, and the surface is excited. The high inconsistency of receiving conditions leads to the prominent problem of static correction. Secondly, the difference between surface conditions and excitation factors, plus the complex faults in the middle and deep and the complex fault systems derived from them. The characteristics of interference wave (frequency, apparent velocity, etc.) of seismic data vary greatly, and some disturbances (such as surface wave, refraction, environmental noise, etc.) are difficult to distinguish from effective waves, which will make the denoising work more difficult. Because of the complexity of surface features, there are significant differences in the energy, frequency and phase of the received signals between adjacent gun sets, within each channel and at different times, which results in a great difference in wavelet. After the seismic wavelet passes through the geodetic filter, the original phase characteristics are changed, and the frequency is reduced, and the formation resolution is reduced. There are many problems in seismic exploration in volcanic rock overlying area. This paper analyzes the characteristics of seismic data and the difficulties in processing seismic data in the working area. The accuracy and effect of the velocity model of static correction are tested in static correction. In the aspect of de-noising, the characteristics of interference wave in single gun are analyzed by sections, and the corresponding processing parameters are taken according to the characteristics of interference wave in this section. The method of de-noising is used to test the suppression effect of various jamming waves. In deconvolution, the surface consistent deconvolution method is used to verify the effect of wavelet compression, to eliminate the influence of surface factors on amplitude and wavelet, and to improve the resolution. A suitable processing method for seismic data processing in this area is obtained. It is shown that the static correction of tomography can obtain a more accurate shallow velocity model and obtain good statics effect. Many kinds of interference waves can be suppressed by using multiple denoising techniques. Surface consistent deconvolution can compress wavelet and eliminate the influence of surface factors on amplitude and wavelet. Finally, the reliability of the processing results is verified by comparing the seismic section with the single shot section, which is of guiding significance to the processing of seismic exploration data in volcanic rock overburden area.
【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】：2016
【分类号】：P631.4

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