北部湾盆地海中凹陷地层特征地震识别研究

发布时间：2018-11-16 21:23

【摘要】：北部湾盆地多期构造演化及沉积沉降中心迁移,使得不同凹陷存在沉积差异,由于缺乏钻井资料,海中凹陷地层结构研究及盆地主要烃源岩层流沙港组二段(流二段)预测均十分困难。依托三维地震资料联片处理,基于层位标定及初步建立的构造框架模型,运用地震相类比、地震属性和测井约束反演等技术,由定性类比到定量分析,对北部湾盆地涠西南凹陷及海中凹陷沉积地层进行了地震识别研究。研究认为海中凹陷与涠西南凹陷流沙港组二段、流沙港组三段(流三段)地震相、均方根振幅及波阻抗等属性的变化具有对应层段高度相似的特点,据此类比建立海中凹陷地层建造,查明该凹陷流二段、流三段地层分布特征。结果表明,海中凹陷与涠西南凹陷古近系地层特征相似,流沙港组具相同沉积演化过程,海中凹陷流三段为水动力条件较强的砂泥岩互层沉积,流二段与涠西南凹陷完全一样,发育相对稳定的湖相泥岩相沉积,即存在良好的烃源岩条件。此认识与HZ2井钻井结果吻合,表明该凹陷具有良好的油气前景,为下一步油气勘探提供了科学依据。
[Abstract]:The multi-stage tectonic evolution and the migration of sedimentary subsidence center in Beibu Gulf Basin have resulted in different depositional differences in different sag, due to the lack of drilling data. It is very difficult to study the stratigraphic structure of Haizhong sag and to predict the second member (second member of flow) of the main source rock formation of the basin. Relying on 3D seismic data processing, based on horizon calibration and preliminary structural frame model, using seismic analogy, seismic attributes and logging constraint inversion techniques, from qualitative analogy to quantitative analysis. The seismic identification of sedimentary strata in Wei Southwest Sag and Haizhong Sag in Beibu Bay Basin is studied. It is considered that the variation of seismic facies, mean square amplitude and wave impedance of the second member of the Lioshagang formation, the third member of the Liushhagang formation, the third member of the Liushagang formation, and the amplitude of the mean square root and the wave impedance of the Huizhong Sag and Wei Southwest Depression have the characteristics of similar height of the corresponding strata. The stratigraphic formation of Haizhong sag is established by analogy, and the stratigraphic distribution characteristics of the second member and the third member of flow in the sag are found out. The results show that the characteristics of Paleogene strata in Haizhong Sag and Wei Southwest Sag are similar, the Liushagang formation has the same sedimentary evolution process, the third member of Liu formation in Hazhong Sag is composed of sand and mudstone interbedded with stronger hydrodynamic conditions, and the second member of Liu2 is exactly the same as Wei Southwest Sag. Relatively stable lacustrine mudstone deposits exist in good source rock conditions. This understanding coincides with the drilling results of HZ2 well, which indicates that the sag has a good prospect of oil and gas, which provides a scientific basis for oil and gas exploration in the next step.
【作者单位】：中国石油化工股份有限公司江苏油田分公司勘探开发研究院;
【基金】：中国石油化工股份有限公司项目(P14088)资助~~
【分类号】：P631.4

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