基于XGBoost算法的吸水剖面预测方法研究与应用

XGBoost-based water injection profile prediction method and its application

胜利海上埕岛油田22F井区地质情况复杂,储层平面和纵向非均质性严重,制约了油田的注水开发效率。准确把握油藏各层间的注水情况是进行油藏治理的重要前提,对于编制合理的注水开发方案也具有重要的指导意义。提出一种基于数据驱动的吸水剖面预测方法,利用Extreme Gradient Boosting(XGBoost)算法建立吸水剖面预测模型,根据油藏的地质参数和动态生产资料预测各注水井在整个开发时段内的吸水剖面演化规律,从而为合理生产配置和注采方案调整提供高质量的基础数据。在埕岛油田22F井区的应用结果表明,基于XGBoost算法建立的吸水剖面预测方法能够实现吸水剖面的准确反演和预测,平均相对误差为0.04,决定系数为0.87,均方根误差为3.12。与KH劈分方法相比,模型预测值与实际吸水量的吻合度更高,更能反映油藏的实际吸水情况,为油田的精细分层注水和智能开发夯实了基础,提供了技术支撑。

The complicated geological conditions and the strong horizontal and vertical heterogeneity of the reservoir severely restrict the water injection development efficiency of 22F Well Block in offshore Chengdao Oilfield,Shengli Oil Province.Accurately identifying the water injection situation of layers in a reservoir is an important prerequisite for reservoir management.It also has important guiding significance for the formulation of a reasonable water injection development plan.Therefore,a data-driven method is proposed for water injection profile prediction in this paper.The Extreme Gradient Boosting(XGBoost)algorithm is used to construct a model for making water injection profile prediction,with which the evolution of the water injection profile of each water injection well during the entire development period is predicted using the geological parameters and dynamic production data of the reservoir.As a result,high-quality data can be provided for rational production allocation and injection-production scheme adjustments.The application results in 22F Well Block of offshore Chengdao Oilfield show that the proposed method can accurately inverse and predict the water injection profile with an average relative error of 0.04,a determination coefficient of 0.87,and a root mean squared error of 3.12.Compared with the KH splitting method,the model in this paper yields a predicted value more consistent with the actual water absorption.This demonstrates that the proposed method can better reflect the actual water absorption of the reservoir and lays a solid foundation for fine stratified water injection and intelligent development of oilfields.