模糊综合评判法预测油层吸水状况

Predicting Reservoir Absorption Situation Using Fuzzy Com-prehensive Judgement Method

吸水剖面是分析剩余油工作一项重要的基础资料,但实际不可能对每口井都测吸水剖面。根据已有吸水剖面资料井的吸水状况判断没有吸水资料井的吸水状况,显得尤为重要。在实际工作中,根据经验判断油层的吸水能力,准确率低,工作量大。而且由于油层吸水状况受地质因素及开发因素的影响,每个因素对油层吸水能力的影响,往往不能用定量的数学关系式进行描述,而模糊综合评判法能较好的解决这个问题。通过对影响注水井吸水能力的各种地质因素及开发因素的分析,选择井点的砂体类型、与周围油井的砂体连通状况及井距等三个因素,作为判别注水井吸水能力的主要因素,通过建立相应的模糊因素集合,作出吸水状况与各影响因素的隶属关系图版,从而得出注水井各小层的吸水状况。

Absorption section is a important basic information to analyze remaining oil, but in fact it is impossible to test absorption section for every well. So it is important that according to absorption situation of previous absorption information wells to judge absorption situation of no absorption information wells. In actual work, judging reservoir absorption situation by experience has low accuracy and much work. And because reservoir absorption situation is affected by geology and development factors, it usually can not use quantitive mathematical relation to describe the effect of every factor on reservoir absorption capacity, whereas fuzzy comprehensive judgement method can solve the problem better. By analyzing all kinds of geology and development factors which affect absorption capacity of injection wells, we can select well sandbody type, connection situation with surrouding oil wells' sandbody and wellhead spacing as major factors to judge absorption capacity of injection wells. By establishing corresponding fuzzy factor assembly, we can draw subordinate relation map of absorption situation and all kinds of effect factor and thus obtain absorption situation of each layer in injection wells.