沙漠区可控震源地震资料存在“黑三角”强振幅干扰波,给资料处理带来极为不利的影响,“黑三角”干扰波压制困难是目前沙漠区可控震源资料处理的技术瓶颈之一.探讨了沙漠区可控震源“黑三角”干扰波的形成机理,借助数值模拟正演,结合多地沙漠区可控震源和炸药震源实际地震记录,对比分析了可控震源与井炮的“黑三角”干扰波的区别.认为“黑三角”干扰波的特点有:近震源附近能量最强,随着离震源的距离加大能量逐渐变弱,呈杂乱不相干状态,频带从几赫兹到近百赫兹;能量强弱与探区的地震地质条件密切相关;分布范围与低降速带的速度密切相关.开展了防假频时频分析异常振幅衰减、子波统计的异常振幅衰减、f-x域分频异常振幅衰减和非均匀相干噪声衰减等技术应用研究,进行了沙漠区可控震源和炸药震源实际地震资料的“黑三角”干扰波压制处理和RTM偏移成像,结果表明:可控震源资料浅层的处理结果比炸药震源的好,其深层的处理结果比炸药震源的稍差.防假频时频分析异常振幅衰减方法和非均匀相干噪声衰减方法串联应用可获得较好的“黑三角”干扰波压制效果,同时依据多块三维地震资料的处理结果认为:在一般厚度的沙漠区的中浅层勘探中可控震源是可行的,但在巨厚沙漠区的深层勘探中可控震源还存在一定问题,采用深井炸药震源会更好.

处理巨厚黄土塬地区的地震资料时,常规静校正方法难以解决复杂的中、长波长静校正问题,给地震资料处理成果的构造形态和信噪比带来不利影响.为此,分析了常规静校正方法效果不佳的原因;开展了针对巨厚黄土塬地区的静校正处理方法的研究,提出了标志层控制的静校正方法.该方法包括基于标志层构造形态控制的高程静校正、基于初至波叠加的中波长静校正和基于标志层修正的剩余静校正3个递进式的步骤,依次用于消除长波长静校正量、中波长剩余静校正量和短波长剩余静校正量.探讨了上述递进式静校正方法的技术流程和关键环节;参照巨厚黄土塬地区地震勘探实际情况,正演模拟含水平层和不含水平层的二维数值模型数据;分别采用标志层控制的静校正方法、层析静校正等方法进行处理,结果表明标志层控制的静校正方法在一定程度上较好地解决了巨厚黄土塬地区中、长波长静校正不准确的问题.对鄂尔多斯盆地某巨厚黄土塬地区的实际地震资料分别采用标志层控制的静校正方法和层析静校正方法进行试处理,结果显示采用标志层控制的静校正方法得到的处理成果可靠性和品质明显更高,弥补了常规静校正处理技术的不足.

The urgent demand for high quality imaging data,especially high-precision geological structure,is a key problem in the development of YKL gas field.Because of missing near-offset data and low fold of seismic data,well-seismic misfit for structural depth prediction in this region can`t meet the exploration requirement if we only use conventional velocity modeling.Therefore,well-controlled anisotropy grid-tomography technique was adopted to conduct velocity modeling layer-by-layer.Based on precise choosing the reasonable markers and building the initial velocity model in the selected area,we use known logging data to calculate anisotropic parameters within this region.Then we eliminate the influence of large set for stable formation velocity on gas reservoir depth,and from shallow to deep layer by layer inversion on marker layer,update iterative anisotropic parameters,velocity and depth migration imaging until the predicted depth errors from well log and seismic data for each marker layer to be reduced.In addition,it has been confirmed by 3 drilling wells that the misfit between the predicted structural depths respectively from the final seismic migration results and logging depth measurements in this gas reservoir are all within 5m.So we can draw a conclusion that our technique can significantly improve the imaging accuracy for structure and fracture of gas reservoir so as to reduce the risk of production drilling.

Various acquisition methods,shooting and receiving conditions,complex subsurface propagation medium lead to different frequency and wave pattern of the reflection wave group from the same formation,inadequate static correction and inaccurate velocity generate residual moveout,and NMO stretch causes wave pattern distortion;therefore,the CMP/CRP gathers usually exists inconsistency problem after conventional consistency processing,which will impact to dig the potential of the data.Consistency processing is one of the key steps to improve the quality of seismic data processing.Merging processing,time-lapse seismic,transitional zone joint processing,prestack inversion and highresolution & high-precision imaging requires higher consistency of seismic data.Due to the strict requirements of consistency processing in high-precision seismic exploration,the non-rigid matching technology is introduced including its principles,characteristics and implementation,which relies on the similar images and a locally smooth deformation (or displacement) field for matching,to solve problems such as incomplete elimination of residual moveout of CMP/CRP gathers after normal consistency processing.On the basis of conventional preprocessing,firstly,the prestack seismic data is sorted into offset data,and partial offset data is optimized to form model;then,every single offset data is carried out non-rigid matching with model to realize consistency processing.Further application of the non-rigid matching consistency technology in real data reveals its superiority in improving the quality of seismic data and resolution preservation.Therefore,the technique is applicable for time-lapse matching processing,prestack angle gather flattening,prestack CMP/CRP gather flattening,AVA processing,event matching processing of PP wave and PS wave.

This paper introduces a diving wave traveltime tomographic velocity inversion technology based on the natural pixel fat ray technique,namely,its principle,processing flow,main steps,key parameters,influencing factors,and application to the initial velocity model building of depth migration.This inversion technology could reduce the sparsity of the tomographic inversion matrix,thus improving the stability of the velocity inversion by broadening the ray path for the established observed system.The technology could build a near-surface velocity model that is deeper than that obtained using conventional refraction tomography inversion,thus providing a better initial velocity model for depth migration by merging with the deep velocity model reasonably.The field data processing results showed that the proposed technology could eliminate the structure imaging artifacts caused by strong lateral velocity variations in the shallows and improve the sig nal-to-noise ratio of seismic imaging,thus reducing seismic-well depth deviation.

A油区先后进行了两次三维地震观测,二次地震施工的坐标分带、观测系统、面元网格、覆盖次数等诸多采集因素均不相同.分析了在这种非重复性采集条件下进行时移地震资料处理存在的问题,并针对去除两期地震数据采集不一致性所造成的不利影响和消除非油气藏因素引起的地震响应变化,给出了针对性的技术思路和处理对策.主要论述了观测因素一致性处理,相位校正、谱整形、匹配滤波等高保真的精细处理,独立处理与融合处理,以及通过过程质量控制优化地震数据的可重复性.对A油区前、后两期非重复性采集三维地震资料进行了叠前、叠后一致性处理和质量控制,获得了较可靠的剩余振幅数据体.

在碳酸盐岩缝洞储集体为主要地质目标的探区,可以通过绕射波分离与成像来提高对溶洞、裂缝等特殊异常体的刻画精度.基于常规的地震资料处理模块,提出了一种基于反射波层拉平的绕射波分离与成像新方法.利用空间属性建立的共深度点CDP与炮集中各道记录的一一对应关系,完成将叠加数据体层位拉平时间信息映射到叠前炮集中各道记录上,进行叠前炮记录的反射波组拉平处理;在层拉平的基础上根据炮集记录中反射波与绕射波同相轴轨迹的规律性几何差别,采用FK滤波等技术将强反射波分离出去.介绍了关键处理技术,给出了详细的处理流程,并展示了针对物理模型观测数据和实际三维地震资料的应用效果.

Multi-sources seismic data involves in the separation of seismic wavefield and the removal of interference wave. For the technical difficulties of duplicate shot records eliminating, in terms of the different forms of noise in different domains, we convert the multi-sources seismic data from shot domain to common offset domain and then the duplicate shots noise is converted to random noise according to the details of the geometry, followed by using noise removal techniques such as FX deconvolution to remove random noise and thus duplicate shots information is eliminated. This wavefield purification process technique is applied in model data and real data contained the duplicate shots records with a remarkable result. The technique can be applied not only for processing duplicate shot records of the vibroseis intensive shooting seismic data, but also for eliminating duplicate shots and mechanical disturbance in seismic records by other source shooting.

多源地震资料涉及地震波场分离和干扰波的去除处理,针对要解决的重叠炮记录去除技术难点,利用噪声在不同域中表现形式不同的客观规律,根据观测系统的具体情况将炮集处理域转换成共炮检距域或仪器通道号域,使记录中的重叠炮相干噪声转化为随机噪声,采用FX反褶积等噪声去除技术来去除随机噪声,实现去除重叠炮干扰.应用该处理技术对数值模拟资料和实际资料中的含重叠炮记录进行了波场净化处理,取得了较好的波场净化效果.该技术可应用于可控震源密集激发资料中的重叠炮记录的处理,也可应用于其它震源激发记录中的重叠炮、机械干扰等的处理.

Previous exploration and research results show that the carbonate reservoir spaces of the Ordovician Yingshan Formation in Ka-1 3D acreage in Tazhong area are dominated by fractures and dissolution pores.However,recent reprocessed seismic data reveal some bead-shaped and short-axis-shaped high amplitude anomalies in Ka-1 3D seismic data.For this reason,many techniques,such as numeral seismic forward modeling,incoherence detection,palaeogeomorphology restoration and multiple seismic attribute extraction,are integrated to re-predict the Ordovician YingShan Formation carbonate reservoirs in Ka-1 3D acreage.The results show that the zig-shaped strong amplitude anomalies in plane view represent igneous rocks,while strong amplitude anomalies being scattered in plane view and beads-shaped on profile represent carbonate reservoirs with large cavities.These interpretations have been verified by well W20 completed recently.

MD region belongs to mountainous area and has complex near-surface conditions.Therefore,the shooting and receiving conditions in the area is poor,and the seismic data has low signal-to-noise ratio.In order to obtain high-quality raw seismic data,we carried out field acquisition in dry season and rainy season respectively.By contrasting and analyzing the single-shot records and stack profiles obtained in the two seasons,we concluded that the quality of the seismic data acquired in dry season is better.The research result provides a good reference for the follow-up of seismic data acquisition in this region and similar regions.

After conventional high-resolution processing,the CDP gather always appears the inconformity of wave shape in the same reflection wave group,which decreases the resolution of stacking profile. In order to obtain the profile with higher resolution,we probed the potential of further improving the resolution of profile,and pointed out that the key technical point for high-resolution processing is to realize the conformity of wave shape and alignment of time for the same reflection wave group.Then,we proposed a series of technologies for resolution improvement processing,including low-frequency trace muting,spectrum shaping and secondary static correction. Actual application result shows that based on the conventional high-resolution processing,our methods can be used to further improve the resolution and signal-to-noise of the profile.

MD area is characterized by rugged surface and complex subsurface structures.At the high-steep structure area,the S/N of seismic data is low and its velocity is difficult to obtain.Therefore,the structure pattern on migration section has low reliability.We analyzed the processing difficulties for structure ascertaining,and proposed some basic processing techniques,including multi-line joint tomographic static correction,prestack strong interference suppression,wave group consistency processing.Migration velocity field was established by DMO velocity analysis,dense-velocity analysis,combined with velocity scanning and velocity spectrum,and well-controlling pre-stack time migration was calibrated by VSP measured velocity,which improved the reliability of prestack migration of complex structures.The series of processing techniques were applied on actual data from MD,and the result indicates that the S/N of seismic sections was largely increased.

The characteristics of near surface seismic geologic conditions at piedmont zone were analyzed,and the factors causing the uncertainty of structures imaging in piedmont zone were probed.On the basis,fixed stripping-surface statics technique was proposed,a typical 2-D velocity model of piedmont zone was designed.Then,based on numerical simulation data,the overburden amount,stripping depth,filling velocity and the necessity for applying fixed stripped-surface statics was analyzed.The proposed statics technique was used in depth migration,and the result was compared to the depth migration profile after conventional statics technique.The results showed that the proposed technique can effectively improve the accuracy of near surface statics,the accuracy of velocity analysis,and the reliability of structure imaged.

The terrain of YKB area fluctuates greatly,and the velocity of shallow layers has big lateral and vertical changes.So constant re- placement velocity statics can not solve the static problem in this area and the structural trap is hard to be ascertained.Firstly,the problems were analyzed,mainly about the constant replacement velocity altitude statics,refraction statics and tomography refrac- tion statics.The effect of inaccurate replacement velocity on data processing was discussed.On this basis,multi-well VSP jointly controlling replacement velocity static method was proposed.In the method,the measured first break restricts the statics to control its long wavelength tendency and improve the reliability of statics. Actual data was used to analyze the processing results by multi- well VSP jointly controlling replacement velocity and constant re- placement velocity elevation statics,which shows that the former method can more effectively improve the reliability of structures and quality of profiles than the later.

In data processing,dynamite source and vibroseis can be joint- ly used to acquire data.Because the composite wave characteris- tics,frequency,energy,and phase recorded by the two sources are inconsistent,the mismatched problems appear at the joint of the data,and the unique method to solve the problem is removing the inconsistency.The commonly used method at present is to adopt the repeated stack interval of the data from the two sources to cal- culate the matching operator and then to perform the matched filte- ring.This method requires assured composite wave characteristics and high S/N ratio of the repeated stack interval.So a new meth- od,the cascade matched filtering processing technique character- ized by pre-stack multi-points,is proposed,which uses iteration before stack and utilizes stack to improve the stability of the matc- hing operator to realize the consistency of the two kinds of source record.The basic principles and implementation steps of cascade matched filtering method are introduced.In comparison,some ac- tual data are processed by both the conventional method and the new one,indicating that the new method is more effective in impro- ving the consistency of the two kinds of source record than the con- ventional one.

井间地震反射波的主频大约是地面地震反射的10倍,因而井间地震具有更高的分辨率,同时对成像精度的要求也就更高.以VSP-CDP成像方法为例,探讨了影响井间地震反射波成像质量的因素,指出井间直达波可作为检验成像精度的依据;在总结和比较井间和地面地震反射成像方法差异的基础上,提出无需速度建模的走时场延拓反射波成像方法,并推导出弱各向异性介质下纵波的走时延拓方程.实际井间资料的处理结果表明,走时场延拓反射波成像方法较之井间VSP-CDP反射成像方法的成像质量有了质的提高,其成像剖面与地面地震剖面相比,包含了更多的地层信息,由此说明,新的成像方法是可行和可靠的.

In data processing of expanding spread, output frequency is normally affected by earth filtering and NMO stretching and decreases as offset increases,which makes high resolution of final data impossible. We presented a new data processing procedure based on surface consistent deconvolution to solve this problem.After conventional surface consistent deconvolution, data is sorted into common offset gathers and NMO applied, then a second surface consistent deconvolution is run on common offset gathers which eliminates offset related frequency decrease.We are studied the relevant processing steps and compared the data after conventional and novel processing.The positive result verified that this new processing method might raise data resolution and improve data quality effectively.

在进行高分辨率地震资料处理时,长排列资料往往会出现大炮检距的波组低频化现象,使得地震剖面的分辨率降低.提高分辨率是目前高分辨率处理中的一个难点,针对这一难点提出了匹配滤波法处理技术.介绍了该技术的主要处理步骤,并利用数学模型和实际资料进行了匹配滤波法处理和常规处理的对比,处理结果表明,匹配滤波法有效地提高了分辨率.

在详细介绍了本区地震地质条件和资料采集情况的基础上,分析了在本区进行精细资料处理中的难点,指出并讨论了4个方面的关键问题:一次静校正和剩余静校正问题、叠前去噪问题、反褶积问题和速度问题.最后,对比分析了本区三维地震资料新、老处理的效果.