多层疏松砂岩气藏动态储量计算误差分析  

Error Analysis of Dynamic Reserve Calculation in Multi-Layer Loose Sandstone Gas Reservoir

作　　者：王铭显 范子菲[1] 罗万静[2] 宋珩[1] 丁杰 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国地质大学(北京),北京100083

出　　处：《特种油气藏》2017年第6期100-106,共7页Special Oil & Gas Reservoirs

基　　金：国家自然科学基金"基于目标的多层疏松砂岩气藏动态储量评价方法研究"(51204148)

摘　　要：针对多层疏松砂岩气藏动态储量计算偏差较大的问题,利用数值模拟和物质平衡方程,以S气田为例,探讨影响该类气藏动态储量计算结果的主控因素及储量动用比低的原因,并初步提出该类气藏动态储量评价的思路。模拟表明:多层合采使生产数据不能准确反映整个气藏的生产动态,造成动态储量评价出现误差;储层渗透率和厚度显著地影响物质平衡曲线的形状,高渗层曲线上凸,低渗层曲线下凹;渗透率级差是动态储量计算误差的主要来源,气层厚度和井底压力的差异会加剧计算误差,压裂和层间初始压差会削弱渗透率级差的影响,气井配产引起的计算误差可以忽略;拟合数据选取不当以及地层平均压力求取不准确是造成S气田储量动用比低的主要原因;利用误差范围和存在误差的动态储量可反推出动态储量的真实范围。该研究结果可为现场准确评价多层疏松砂岩气藏的动态储量提供参考。Reservoir numerical simulation and material balance equation are used to improve the relatively large de- viation in the dynamic reserve calculation of multi-layer loose sandstone gas reservoir. The S Gasfield is taken to i- dentify the main controlling-factors in dynamic reserve calculation and the causes of low reserve producing level and tentatively propose the idea of dynamic reserve evaluation. Research illustrates that nmhi-layer production history will result in complex characterization of gas reservoir performance and large error in dynamic reserve evaluation. The corresponding material balance curve greatly depending on reservoir permeability and thickness is convex in high-permeability layer and concave in low-permeability layer. The dynamic reserve calculation error mainly results from reservoir permeability contrast and the differences in gas reservoir thickness and bottom-hole pressure will in- crease this error. Fracturing treatment and initial inter-layer pressure difference will weaken the reservoir permeabil- ity contrast and the effect of gas well production allocation on dynamic reserve calculation can be neglected. The im- proper fitting data and inaccurate calculation of average formation pressure are considered as the main causes for low producing level of gas reserve in S Gasfield. The actual dynamic reserve range can be gained by reversing with error range and initial dynamic reserve. This research could provide a reference for the accurate evaluation of dynamic re- serve in multi-layer loose sandstone gas reservoir.

关 键 词：多层气藏 疏松砂岩 动态储量评价 物质平衡法 误差分析 

分 类 号：TE32[石油与天然气工程—油气田开发工程]