地震沉积学及反演技术在Q606块沉积演化研究中的应用

Application of Seismic Sedimentology and Inversion Technology in Sedimentary Evolution Research of Q606 Block

以张强凹陷Q606区块为例提出了针对低井控程度地区的沉积演化研究思路和方法。以地震沉积学理论为指导,以地震反演技术为核心,首次引入波阻抗数据体地层切片对研究区沉积演化史进行了分析。研究结果表明:1)Q606区块沙海组下段早期发育扇三角洲平原和扇三角洲前缘沉积,洼陷区发育近岸水下扇沉积,随着沉积物持续供应,近岸水下扇范围逐渐扩大,晚期洼陷区被填平,随着湖平面上升,整体发育扇三角洲前缘沉积;2)基于地震沉积学原理,在单井相,连井相分析的基础上,通过波阻抗数据体地层切片分析岩性的横向变化,进而开展沉积学解释是低井控程度地区开展沉积演化研究的有效方法。

Taking Q606 block in Zhangqiang sag as an example,this paper researches on the method of sedimentary evolution with low exploration degree.Based on seismic sedimentology,by applying inversion technology,the tectono-sedimentary evolution of Q606 block and sedimentary were studied.The results show that Q606 block mainly develop fan delta system in the early period of Shahai formation,including fan delta plain and fan delta front.Underwater fan system develops in the sag zone.As the sediment continue to accumulate,underwater fan range gradually enlarges.At the end of the bottom member of Shahai formation,the delta fan system develops because of the sag was filled and the lake level rises.Another conclusion is that we can research the sedimentary evolution by the impedance slice with the low exploration degree based on the seismic sedimentology principle and sedimentary facies analysis result.