利用模糊综合分析法识别水驱砂岩油藏注采井间优势通道

Identification of Thief Iones Between Injection Wells and Production Wells of Standstone Reservoirs Flooding by Fuzzy Comprehensive Analysis Method

砂岩油藏由于长期注水开发形成的优势通道导致注入水在注采井间低效、无效循环,严重影响水驱开发效果.有效识别优势通道是油藏提高水驱采收率必须解决的关键问题.采用模糊综合分析法,以地质静态因素为基础,结合动态监测结果,利用变异系数法对指标加权并计算优势通道综合判别参数,定量识别出水驱砂岩油藏优势通道并描述其发育程度.将方法应用于X3油区典型井组优势通道识别并利用吸水剖面法验证其结果准确性.方法可实现软件编程计算,方便快捷、结果准确可靠,能够为油田开发后期制定合理调整方案提供有力依据.

The long-term water flooding development formed thief zone, which leads to injected water inefficient cycle between injection wells and production wells. It seriously affects the effect of water flooding. This is a key problem to improve water flooding recovery for middle and high permeability sandstone reservoir. The fuzzy set theory, the static geological factors and the dynamic results of the tracer-tagged liquids were used to calculate thief zone synthetic discriminant parameters, through the variation coefficient method to weight index. The existence and development of thief zone of water drive sandstone reservoir was q＇aantita- tively identified. Taking the typical well pattern of X3 area for example and calculating thief zone synthetic discriminant parameters. The evaluation results in good agreement with the actual. It is verified this method can accurately identify thief zone and provide a strong basis for making reasonable adjustment scheme of the late stage of oilfield development.