摘要
北部湾盆地徐闻探区南部断阶带,地震资料品质较差。综合区域地质背景和单井岩心相分析认为,南部断阶带为近岸水下扇沉积。在建立该区层序地层格架的基础上,通过剖面分析、速度分析、时频及相干性分析等多种技术手段刻画近岸水下扇体,包括水下扇的期次、形态、范围及发育情况,最终在徐闻探区南部断阶带涠洲组识别出6期扇体。扇体的扇根和扇中互相叠置,扇根为盖层和遮挡层,扇中为储层,可形成有利的储盖组合,作为徐闻探区下步勘探的有利区带。
The quality of seismic data in the southern step-fault zone of Xuwen Exploratory Area was poorer.Based on the regional geological background and core facies,it was considered in analysis that it was a coastal subsea apron deposition in the step-fault zone.On the basis of establishing a sequence stratigraphic framework,the subsea apron was depicted by profile analysis,velocity analysis,time-frequency analysis and coherence analysis,which included the stages shape,range and developmental condition of the coastal subsea apron.Finally,6 periods of fan bodies with cross-superimposition of the root-fan and mid-fan are identified in the step-fault zone.There are special reservoir-cap rock assemblage and barrier bed.This assemblage includes the root-fan for cap-rock and barrier bed,and the mid-fan is a reservoir.The southern step-fault zone is a favorable area of oil and gas exploration.
引文
[1]姜素华,林红梅,王永诗.陡坡带砂砾岩扇体油气成藏特征——以济阳坳陷为例[J].石油物探,2003,42(3):313~317.
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