金湖凹陷西斜坡阜二段储层参数分布特征

Study on reservoir parameters of second member of Funing formation, west slope of Jinhu sag

金湖凹陷西斜坡阜二段(E1f2)储层沉积微相繁杂多样,分布规律复杂,导致储层参数变化快,规律难于把握。针对此问题,研究提出按沉积微相分类讨论储层参数分布规律的方法。金湖凹陷西斜坡阜二段第3亚段(E1f23)1—7小层沉积微相和砂体厚度的变化与展布特征不同,导致储层参数的分布特征差异明显,发育较多原生补给水道沉积的1—4小层比发育较多改造补给水道沉积的5—7小层的孔隙度、渗透率均要高。对研究区内发育的滨湖砂坝、滨湖砂滩、原生补给水道和改造补给水道微相进行分类研究,结果表明,滨湖砂坝和滨湖砂滩孔隙度、渗透率分布相对稳定,渗透率呈较明显的复合韵律分布模式;原生补给水道渗透率多呈正韵律分布模式;而改造补给水道渗透率多呈反韵律或复合韵律分布模式。储层物性平面上呈北东—南西向展布,其高值区主要分布于原生补给水道和砂坝沉积区,低值区则分布于改造补给水道和砂滩等沉积区。

There are variable sedimentary microfacies in the work area,and the distribution rule is complex,and the reservoir parameters are changed quickly,so,the rule of it can not be described easily.In view of this problem,the method of studying the distribution rule of the reservoir parameters based on sedimentary microfacies is established herein.And,the microfacies of sand bar,sand beach,primary feeder channel,modified feeder channel are used to study the distribution rule.The porosity and permeability of the sand bar and sand beach reservoir are constant,and the permeability model of this microfacies is complex-rhyme,the permeability model of primary feeder channel is positive rhythm,the permeability model of modified feeding channel are inverted rhythm and complex-rhyme.The distribution of the sedimentary microfacies and the thickness of sand body of the E1f23 lead to the difference of the distribution of the reservoir parameters.The porosity and permeability of the sub-layers of E1f23-1-E1f23-4 with more primary feeding channel are higher than the sub-layers of E1f23-5-E1f23-7 with more modified feeding channel.The reservoir parameters in plane is distributed in northeast-southwest direction,the high value of the area is developed in the microfacies of sand bar and primary feeding channel,and the low value of the area is developed in the microfacies of sand beach and modified feeding channel.