石油与天然气地质 ›› 2011, Vol. 32 ›› Issue (3): 404-410.doi: 10.11743/ogg20110313

• 石油与天然气地质 • 上一篇    下一篇

临南洼陷三角洲地震岩相解释方法

  

  • 出版日期:2011-06-28 发布日期:2011-09-23

Seismic lithofacies interpretation of delta deposits in the Linnan subsag

  • Online:2011-06-28 Published:2011-09-23

摘要:

摘要:惠民凹陷西南部临南洼陷沙三段浊积岩发育规模小、数量多、分布广。以砂组为单元的储层预测容易漏掉地震特征不明显的砂体,难于实现浊积岩的整体预测。在遵循层序及砂组“等时性”和沉积等相“穿时性”对比原则基础上,由地质相、测井相和地震相建立了岩相的三元信息识别模式。通过层序、岩相和砂组单元的构造、厚度与储集体的地震属性研究,形成了岩相单元的浊积岩储层预测三步法:三级层序定古地貌,岩相定区带,砂组定储层。该方法在临南洼陷中应用并取得了良好效果:建立了远砂坝与泥岩、远砂坝与浊积岩、河口坝与泥岩、河口坝与浊积岩4种三角洲前缘亚相与前三角洲亚相的接触模式;落实了多个前三角洲亚相的相构形,预测了洼陷带浊积岩有利发育区,为临南洼陷浊积岩油藏的整体评价和勘探部署提供了可靠依据。

关键词: 关键词:三角洲, 浊积岩, 地震岩相, 储层预测, 沉积相, 临南洼陷, 惠民凹陷

Abstract:

Abstract: Turbidite in the third member of Shahejie Formation in Linnan subsag features in small,size,large number and wide distribution.It is hard to fully predict turbidites,because the sandbodies with ambiguous seismic features could be easily missed in reservoir prediction when taking sand group as unit.Based on the principles of isochronism in sequence and sand group and diachronism in sedimentary isochronfacies,this paper establishes the recognition modes of lithofacies with ternary information including geologic facies,well log facies and seismic facies.By studying the structure,thickness and seismic attribute of the reservoir based on the unit of sequence,lithofacies and sandgroups individually,a threestep method is developed for the prediction of the turbidite reservoir in the unit of lithofacies: defining palaeotopography according to thirdorder sequence,determining plays according to lithofacies,and delineating reservoir distribution according to sand groups.The method has been successfully applied in Lunnan sag: four kinds of contact models between the delta front and prodelta subfacies were established,i.e.distal sandbarmudstone,distal sandbarturbidite,mouth barmudstone,and mouth barturbidite.The shape of multiple prodelta subfacies is defined,and the favorable turbidite reservoirs are predicted,laying a reliable basis for turbidite evaluation and exploration deployment in Linnan subsag.