【摘要】 依据地震波波形理论,进行地震相自动识别、划分,可确定沉积体系平面分布特征。与传统方法相比较,该方法具有更省时、更客观、更准确的优势。利用此方法研究了渤海湾盆地孤南洼陷沙三中亚段中部地层沉积体系平面分布规律。相模型道与沉积相具有较好的响应关系,其对沉积相变化较敏感,可用于微相划分。研究表明,孤南洼陷沙三中亚段中部地层沉积时期,存在辫状河三角洲、盆底扇和湖泊3种沉积体系。辫状河三角洲在该区发育前缘亚相,分布于孤南洼陷南部斜坡区域;盆底扇主要分布于洼陷北部,位于孤南断裂坡脚部位,浅湖近岸滩坝滑塌也可形成盆底扇复合体。该时期的湖泊较浅,主要发育浅湖亚相,近岸滩坝及席状砂也较丰富。更多还原

【Abstract】 According to the seismic waveform theories,the seismic facies have been identified and divided automatically and the plane distribution of the depositional systems have also been determined.Compared with the traditional methods,this method has the advantages of saving time,more objective and more accuracy.Using this method,the plane distribution of the depositional system of the middle part of middle submember of the 3rd member of Shahejie Formation has been studied in Gunan Sag of the Bohai Bay Basin.There is preferable relationship between the seismic facies models and the sedimentary facies,and at the same time,they are sensitive for sedimentary facies changes,therefore,can be used for microfacies division.It indicates that three depositional systems,including braided-river delta,basin floor fan and lake depositional system,were existing in the Gunan Sag at this time.The front subfacies of the braided-river delta was developed in the south slope of Gunan Sag.The basin floor fan was mainly distributed in the north of the sag,located in basal slope of the Gunan fault.In addition,the slump of the nearshore strand bar also can form basin floor fan complex.In this period,the nearshore strand sandstone bar and sheet are more abundant.更多还原