地震数据采集得到的地震波是由反射波、规则干扰和噪声叠合而成的复合波,数据处理将淹没在干扰和噪声之中的反射波提取出来,再经过频率补偿使反射波高频成分的微弱振幅得以提升,从而得到主频高、频带宽的高分辨率数据.记录下来的反射波频率的高低,不能用"60 dB高频死亡线"来衡量,用原始数据滤波扫描也得不到反射波频率的正确范围,而用采集+处理综合动态范围和地层吸收衰减模型可对反射波频率范围作出较客观的估计.对处理后的数据进行滤波扫描,才能得到正确的反射波频率范围.塔里木盆地沙漠区2 ms采样间隔的常规处理数据高通滤波扫描结果表明,反射波频率可高达尼奎斯特频率(约240 Hz),证明井中激发、地面接收采集到的数据已记录了这样的反射波高频成分.特征子波反褶积处理的实例证明了这样的微弱振幅高频成分是展宽高频段的有用信号.然而1 ms采样间隔的高精度数据经叠前时间偏移处理,其反射波高频仅达到120 Hz,甚至更低至60 Hz.之所以如此,是叠前时间偏移前的滤波和频率衰减所致,这种做法变相地将1 ms采样的高精度数据当作4 ms甚至8 ms采样间隔数据使用.此外,抽稀时间和空间采样间隔的算法和处理措施会使反射波高频成分成倍降低.

漏磁检测技术在我国管道腐蚀检测上应用广泛,从漏磁检测技术原理着手,分析了其国内研究及应用现状,指出了存在的问题及今后的发展趋势.

The detection of layers which thickness(height) is less or far less than λ/4(such as thin coal bed and thin sand reservoir) have become an important target for seismic exploration,so do the irregular 2-D(such as undercurrent) and 3-D bodies(such as caves) thinner than λ/4 with limited width or with limited width & length.In recent years,researchers have made some progress on the above targets.However,it is doubted that the layer with thickness(height) smaller than λ/4 can be detected.The definition of the conventional seismic resolution such as λ/4(Rayleigh or Ricker) or λ/8(Widess) is by using the characteristics of seismic wave to verify the thickness of thin layers,which can be used to answer "how thin for a thin layer".Therefore,the above resolutions should be called as "Resolution on thickness of thin layer".This kind of resolution is not adaptive to estimate whether the bed is detectable.Research indicates that the essence of thin layer can be detected is that its reflection(attributes) could be distinguished from its background(attributes).In terms of this theory,one new resolution is presented,which is called as seismic detectable resolution.The seismic detectable resolution answers the questions of "what is the minimum thickness of detectable thin bed" and "what is the minimum size of detectable irregular body".In the paper,we discussed some quantitative indexes for the detectable resolution of thin layers and irregular bodies,and displayed some detection samples for thin coal bed,carbonate carven reservoirs and thin sand reservoirs.

Since it is unreliable to identify and pick refraction wave from underground continuous layers in those areas with drastic variation of topography as well as lateral variation of velocity and thickness, refraction static correction technology is limited in calculating static correction value of long wavelength with high precision. A 3-D static correction technology based on Correlation Refraction Method is proposed to pick first break and calculate absolute delay time precisely, eventually refraction static correction is performed by delay time and near-surface model. Result from real data processing shows that this approach can substantially improve the quality of seismic stack sections in areas with complex near surface conditions such as loess table land, desert and the commissure between desert and mountainous region.

四川盆地东北部的三叠系下统飞仙关组是重要的油气储层,其储集岩体主要为经晚期白云岩化改造的鲕滩坝沉积的致密鲕粒白云岩、鲕粒灰岩.铁山坡地区位于开江-梁平海槽的东北边缘,具备发育飞仙关组鲕滩储层的条件.但是,复杂多变的围岩和严重的非均质性增加了储层预测的难度,为此,在储层预测中采用了基于信息融合理论的地质模型约束地震反演,把地质、测井、地震等多元地学信息统一到同一个模型上,将各类信息在模型空间进行有机融合,提高了反演的信息使用量、信息匹配精度和反演结果的置信度.同时,利用空间地质约束相干识别技术对储层的含气、含水及气水关系等进行了检测和识别,检测结果与钻井资料吻合.

Along with more and more volcanic reservoirs are discovered, volcanic rock is attached with more importance as oil and gas reservoir. Because of some particularity of volcanic rock in physical properties and reservoir space, some traditional methods and technologies suitable for reservoir prediction may be unsuitable for volcanic reservoir prediction. The volcanic reservoirs should be predicted by agilely using the existent technologies. The seismic prediction of trachyte reservoir in the third member of Shahejie Formation in Huangshatuo Oilfield of Liaohe Depression was made. The practicable seismic technologies such as fine structure interpretation, multi-well constrained impedance inversion, model-based reservoir parameter inversion and fracture prediction with resistance difference and ratio are reasonable in prediction and description of the trachyte reservoirs. The predicted result is coincident with drilling data.

Seismic wave field feature of Ordovician carbonate karst reservoir (cave,reef,hole,crack and cranny )in Tahe oil field is thedifference magnitude diffraction wave over weak reflection amplitude,so,the diffraction wave exact imaging and fidelity amplitude processing is the basic of carbonate karst reservoir study.The paper,by the real seismic data high fidelity processing with post-stack high precision migration arithmetic and true amplitude in Tahe oil filed , summed up a set of post-stack seismic data high fidelity amplitude processing technology to adapt the area Reservoir prediction.

叠前深度偏移的效果如何取决于建立的速度-深度模型正确与否.通常以叠后偏移数据的构造解释结果为构造背景,以叠加偏移的均方根速度为初始速度,来制作初始速度-深度模型,然后再经反复迭代,求得最终的速度-深度模型.但是,当构造复杂、速度变化剧烈时,叠偏剖面成像差,不能得到正确的构造,使这种制作速度-深度模型的方法难以得到预期结果.以EAGE/SEG盐丘模型为例,探讨了在从叠加偏移剖面中无法得到正确构造形态和速度的情况下,采用叠前逐层成像速度建模的方法来求取叠前深度偏移速度-深度模型的处理方法,并将其应用于实际地震数据处理,得到了成像效果良好的剖面.

寻找碳酸盐岩油藏的关键就是要找到充满流体的大型溶洞.塔河油田的勘探实践表明,应用频率差异分析技术可以有效的鉴别溶洞充填物的性质.当溶洞全为流体充填时,其地震波具有强振幅、低速度及调谐性的特征;当充填粘稠的半流体时,其调谐反射相当于绝对反射的900/0;当充填物为疏松沉积物时,其调谐反射也相当于绝对反射的770/0.以上几种介质,都很有可能是油的储集体.对于主频集中在20～30Hz的反射波而言,只要溶洞高度在2～3 m以上就能识别.该技术在塔河油田进行了应用,其连片三维区溶洞分布层及纵、横向连通情况清晰可见;在S48井中的风化面下,发现了4层古暗河.

一个炮点和一个检波点接收的一道地震记录上某一时刻振幅值,它可能来自地下一个椭圆面上各个点的反射,该椭圆面以炮点和检波点为焦点,炮点和检波点的连线为长轴.因此,在叠加时,该振幅值就不是只在共中心点(CMP)上相加,而应该在椭圆面上各个点相加(当然,在不同点上振幅值是变化的).这种叠加方法实现了共反射点叠加,有利于叠加成像,也有利于提高分辨率和信噪比.这就是克希霍夫求和法.

分析目前三维地震勘探中产生的数据量庞大、采集处理周转时间延长及勘探成本增加等问题,指出高速网络通讯技术和小波数据压缩技术的利用是解决这些问题的有效手段,介绍这种方法的经济效益,并进行了前景展望.