Arps递减曲线与甲型水驱曲线的相关性及参数计算

Ａｒｐｓ产量递减曲线和甲型水驱曲线表达了大部分水驱油藏的基本规律。确定Ａｒｐｓ产量递减曲线的两个参数（产量递减率和递减指数）的传统方法是通过拟合生产历史（产量）获取，但存在拟合历史应取多长、预测范围应多大这两个问题。从甲型水驱曲线出发，提出了甲型水驱油藏的产量、递减率、含油率的预测模型，确定了Ａｒｐｓ产量递减曲线的两个参数与含水率、产油量、动态地质储量之间的关系。对不同的开发阶段，甲型水驱曲线可用几条含油率与累计产液量之间的双曲递减曲线分段描述。在产液量基本稳定的情况下，产油量与时间之间的关系也满足双曲递减规律，其递减率与年产油量、含水率成正比，与地质储量系数成反比；而递减指数取决于水油比。给出了Ａｒｐｓ曲线与油田生产历史能够吻合的范围和预测区间的大小，以及Ａｒｐｓ曲线与甲型水驱曲线的相关性。针对产液量基本稳定的生产过程，还给出了产油量的预测模型，用该模型预测产油量可到产油量初值的１／４～１／２，生产历史可拟合到产油量初值的１．２～１．５倍。在拟合预测区间内，甲型水驱曲线上的直线段与相应的Ａｒｐｓ递减曲线具有相同的开发特征。图３表２参３（裴连君摘

Correlativity of Arps production decline curve vs. Type A water drive curve and their parameter calculation.

Arps production decline curve and Type A water drive performance curve can be used for most water drive reservoirs. In the traditional methods the Arps production decline curve's two parameters, production decline rate and decline exponent, are generally obtained by matching production history (oil rate). But there are two problem here: How long the fitting history should take? And how far the prediction should be? Based on Type A water drive curve, this paper proposed a prediction model of Type A water drive reservoir, including oil production, decline rate and oil cut, and determined the relationship between two parameters of Arps production decline curve and water cut, oil production and dynamic geologic reserve. For different development phases, Type A water drive curve can be described in step by several hyperbolic decline curves of oil cut versus cumulative liquid production. If the liquid production is stable, the relationship between oil production and time meets hyperbolic decline curve, the decline rate is directly proportional to annual oil production and water cut, and is inversely proportional to geological reserves coefficient. While, the decline index depends on water oil ratio. This article provides the range within that Arps curve can fit oilfield production history and the size of prediction interval, and also presents the oil production prediction model. Using this model, the predicted oil production can reach initial 1/41/2 values, and the matched production history can reach 1.21.5 times of initial oil rate value. The straightline section on Type A water drive curve has the same development feature with the corresponding Arps decline curve in matching prediction interval.