苏丹Fula油田辫状河储层内夹层沉积成因及井间预测

Sedimentary origin and interwell prediction of interbeds in braided river reservoir, Fula Oilfield in Sudan

关键词:  层序地层学  辫状河  夹层  沉积成因  井间预测  多点地质统计  Fula油田

Key words:  sequence stratigraphy  braided river  barrier and interbed  sedimentary origin  interwell prediction  multi-point statistics  Fula Oilfield

摘要:

针对辫状河储层内隔夹层的复杂结构特征,依据沉积学及高分辨率层序地层学基本原理,对Fula油田辫状河储层内隔夹层的沉积成因及井间预测方法进行研究。结果表明:废弃河道、坝间泥、心滩落淤层、越岸沉积是构成辫状河夹层的主要沉积类型,泥质沉积物的保存与可容纳空间、沉积物供给速度有着密切联系;在沉积成因分析基础上,可根据单井测井解释和连井对比来描述各类夹层的空间形态,建立夹层的沉积模式;在辫状河相储层中,应用多点地质统计学方法预测井间泥质夹层分布,可以更有效地体现夹层的几何形态和分布规律,其更加符合辫状河夹层的沉积模式。

Abstract:

According to the characteristics of complicated reservoir architecture of braided river and based on the basic principle of sedimentology and high resolution sequence stratigraphy, sedimentary origin of interlayer and interbed were analyzed and a method was proposed for predicting impermeable layer between wells. The results show that abandoned channel, interbar mud, fall silt and overbank are main origin types in barrier and interbed construct. Preservation of muddy deposition is closely related to accommodation space and sedimentary alimentation. Based on analysis of deposit genesis, shapes of different interbed types of mud were described according to single well log interpretation and well correlation. And sedimentary model of barrier and interbed was developed. Furthermore, the sedimentary model can be used in constructing training image after optimal selection. Prediction of barrier and interbed achieved by multi-point statisctics can effectively reflect the geometric morphology and distribution of interbed, which is more consistent with the sedimentary model of the braided river.