【摘要】 为精确揭示高精度层序内沉积体系的三维几何形态及沉积演化特征,采用小波能谱分析手段,建立准层序组的三种叠加模式,以小波能谱的准层序叠加样式、振幅谱尺度突变点以及能谱聚类规律划分高频等时层序;结合地震反演、属性分析等手段,应用地层切片技术,对塔南凹陷南屯组SQ21时期进行沉积发育史研究。结果表明,研究区发育扇三角洲及水下扇沉积,随着沉积物供给能量的减弱,沉积体系表现为一种沉积规模由老到新逐渐向后(逆物源方向)萎缩、沉积物粒度逐渐变细的时空配置关系,到最大湖泛时期湖相全区发育,扇三角洲和水下扇沉积规模萎缩至全区最小,水下扇是扇三角洲前缘砂体二次搬运后再次滑塌而成。更多还原

【Abstract】 To reveal the 3D geometry of depositional system and characteristics of sedimentary evolution in high-resolution sequence,we adopted the method of wavelet energy-spectrum analysis,builded up three stacking model of subsequence sets,and divided high-frequency and isochronal sequence by stacking model of wavelet energy-spectrum,change of amplitude spectrum and energy-spectrum’s clustering regularity.Combined with the methods of seismic inversion and attributes analysis,we studied the sedimentary evolvement of SQ21 stage in the Nantun Formation of Tanan Sag,applying the technique of statal slice.The results showed that the deltaic fan and subaqueous fan were developed in the studied area,and depositional system represented the time-space model that depositional scale gradually rearward fade from older to younger and depositional size gradually attenuated with the slacking of sediment energy.Lacustrine facies developed in all area during the period of maximum flood.The scale of deltaic fan and subaqueous fan faded minimal in all area,and subaqueous fan was formed by the secondary transported and slumped of sediment of deltaic fan.更多还原