Wide azimuth (WAZ) seismic is a seismic acquisition with a ratio of transverse to longitudinal receiver unit size larger than 0.5.Using WAZ seismic acquisition,a 3D seismic data volume with observation azimuth,offset and uniform folds can be economically obtained.With Offset Vector Tile (OVT) processing,5D seismic prestack gathers may be generated from WAZ seismic data,enabling 5D seismic data interpretation (5D seismic data is the 3D WAZ seismic data including offset and azimuth information).This paper first gives an overview of WAZ and OVT,their evolution and innovations on seismic interpretation.Then,the theoretical foundations of 5D seismic interpretation in the OVT domain is addressed based on anisotropy theory.Discussion focuses on 5D seismic interpretation,including structure interpretation,stratigraphic interpretation,lithologic interpretation,fluid identification,fracture prediction and earth stress study.Theoretical analysis and data tests showed that 5D seismic interpretation of OVT gathers could help improve azimuthal anisotropy analysis and interpretation validity.OVT processing is more than a technology,but a thought.Interpretation of 5D seismic gathers in the OVT domain is a general trend of seismic interpretation.%宽方位地震技术是横向接收单元尺寸与纵向接收单元尺寸之比大于0.50的三维地震采集、处理和解释技术.通过设计宽方位观测系统有效地采集到高品质的地震数据体,经过炮检距向量片(OVT)等技术处理,获得OVT数据域的五维(即空间三维坐标+炮检距+方位角)叠前地震道集,为五维地震资料解释奠定了资料基础.以OVT域五维地震解释为主线,首先介绍了宽方位地震采集和OVT处理技术的发展历程,探讨了OVT技术对宽方位地震资料解释带来的革新及在OVT域进行地震资料解释的必要性;其次基于各向异性理论,论述了OVT域地震资料五维解释的理论基础.理论及实例研究表明,基于OVT域五维地震资料可有效地实现方位各向异性分析与研究,显著提高地震资料解释(构造解释、地层解释、岩性解释、流体识别、裂缝预测及地应力研究)的精度和准确性.OVT域五维地震资料解释不仅是一项技术,更重要的是一种思想,五维地震数据的解释将是地震技术的又一次革命.
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