基于测井响应特征的砂质辫状河泥岩成因分类——以渤海L油田为例

Genetic Classification of Sandy Braided-river Mudstone Based on Logging Response Characteristics——Taking L Oilfield in Bohai as an Example

辽东湾馆陶组储层为典型辫状河沉积,是渤海重要油气产层之一。根据测井响应特征分析结果,建立泥岩分类方案,探讨各类泥岩沉积成因,并以井间对比关系研究为基础,结合类比分析结果,预测各类泥岩平面展布规模。结果表明:渤海L油田辫状河泥岩包括洪泛泥、漫溢相泥和河道内泥3类;洪泛泥厚度多大于6m,平面分布稳定,预测平面展布范围大于1 500m,连续性强,属于隔层;漫溢相泥单层厚度多大于2m,在局部范围内展布较连续,预测平面展布范围一般大于300m,影响储量动用;河道内泥厚度多小于2m,分布局限,预测平面展布范围小于200m,平面连续性较差,影响了水平井斜穿层布井方式。上述成果有效规避了储量动用风险,对开发井型的合理选择和部署具有重要的指导意义。

Guantao Formation reservoirs in Liaodong Gulf,which are important oil and gas reservoirs in Bohai,are typical braided-river deposits.According to the analysis results of logging response characteristics,the classification scheme of mudstone was set up,and the sedimentary geneses of all kinds of mudstone were discussed;the plane scales of all kinds of mudstone were predicted based on the well-to-well correlation,combined with the analysis results of analogy.The results show that the braided-river mudstone of L oilfield in Bohai includes flooding mud,overflow facies mud and channel mud;the thickness of flooding mud is mostly more than 6 m,and it has stable distribution with predicted scale of more than 1 500 m,which belongs to interlayer with great planar continuity;the single layer thickness of overflow facies mud is usually more than 2 m,and this mud is continuous in local areas with predicted scale of more than 300 m,which affects reserve utilization;the thickness of channel mud is usually less than 2 m with bad continuity,and it has a limited planar distribution of less than 200 m,which has an influence on the pattern of horizontal well inclined to formation.The above results easily avoid reserve risk and have an important guiding significance to the choice and deployment of development well-type.