泌阳凹陷南部陡坡带核三上段沉积相研究

Sedimentary facies of upper Eh3 on the south steep slope zone of Biyang depression

对泌阳凹陷南部陡坡带核三上段岩石颜色、岩石类型、沉积构造、古生物标志、测井相等相标志的综合分析,从而对其沉积相类型及特征进行研究。研究认为,泌阳凹陷南部陡坡带核三上段沉积期发育扇三角洲、辫状河三角洲和湖泊3种沉积体系。扇三角洲及辫状河三角洲主要发育三角洲前缘和前三角洲2个亚相,缺失三角洲平原亚相。三角洲前缘亚相可进一步划分为水下分流河道、水下分流河道间、河口砂坝、远砂坝、席状砂等沉积微相。湖泊相沉积则以半深湖—深湖泥沉积为主。

The sedimentary facies and characteristics of the upper Eh3 on the south steep slope zone of Biyang depression have been studied through comprehensive analysis of rock color,rock type,sedimentary structure,palaeontologic marker and electrofacies.The study shows that three sedimentary systems had developed in the upper Eh3 on the south steep slope zone of Biyang depression,which were fan delta,braided river delta and lacustrine facies.Fan delta and braided delta had developed two main subfacies of delta front and predelta,with the absence of delta plain subfacies.The delta front subfacies can be further divided into sedimentary microfacies of underwater distributary channel,underwater distributary interchannel,mouth bar,distal bar and sand sheet.The lacustrine facies was dominated by semi-deep and deep lake mud deposition.