苏德尔特油田兴安岭油层微观孔隙结构特征

针对海拉尔盆地苏德尔特油田兴安岭油层注水效果差、产能低的实际情况,开展了微观孔隙结构特征研究。确立了合理的喉道分类标准,将细喉道和吸附喉道之间的界限定为0.1μm。从孔隙分布特征、喉道大小、喉道分布范围及形态、渗透率贡献、储集空间及渗流通道、流动喉道下限、贾敏效应、可动流体饱和度等方面进行分析研究。各区块喉道大小及分布差别很大,以双峰型为主。储层物性受喉道控制,渗透率贡献率分布呈单峰且峰值在右。兴安岭油层平均喉道半径小,流动喉道下限低,储集空间与渗流通道不对应,贾敏效应阻力大,可动流体饱和度低是造成注水效果差、产能低的根本原因。提出了正方形井网中心加密油井的调整方式,见到了较好的开发效果。

Characteristics of Pore Structure of Xing'anling Pay Zone in Suderte Oilfield

Research on characteristics of pore structure of Xing’anling pay zone in Suderte oilfield is made,in view of the problems of poor effect of waterflooding and the low productivity.The reasonable classification criteria of throat is determined.Classification limit between fine throat and absorbing throat is 0.1μm.The research is based on pore distribution feature,throat size,throat distribution range and its form,permeability contribution,storage space and fluid flowing channel,flowing throat limit,Jamin effect,movable fluid saturation.There are big differences in the throat size and the distribution.Throat distribution takes on dual peak,and micro-heterogeneity is very serious.Formation permeability is controlled by throat.Permeability contribution takes on single peak and peak value locates right site.Large scale throat contribute much to permeability.The fundamental reason of waterflooding and the low productivity in Xing’anling pay zone is that throat is small,flowing throat limit is low,storage space does not match flowing space,Jamin effect is large,and movable fluid saturation is small.Infilling oil well,method in the center of square well pattern is proposed and the better development result is obtained.