泵抽式电缆地层测试关键点及曲线优化新方法

Optimization method of key test point picking and best plot choosing from pumping wireline formation test data

泵抽式电缆地层测试时,关键测试数据点的准确选取和最佳测试曲线的合理确定是保证其解释结果真实可靠的首要环节。充分考虑了泵抽式电缆地层测试器能够同时提供多种地层流体测量数据和仪器控制参数的有利条件,从电缆地层测试渗透率解释的基本原理出发,研究了某海上油田512组实际压力测试和取样测试曲线,运用数值微分方程和模糊综合评判模型,建立了综合使用多种测量参数共同确定压降测试起始点等7个关键数据点和最佳测试曲线的最优化方法。使用该方法开发的计算机软件对新型国产泵抽式电缆地层测试器(ERCT)109个层位的实测数据进行了渗透率解释,证明该方法不仅能够提高解释精度,而且消除了人工选择测试曲线和关键数据点所带来的解释结果因人而异的弊端,保证了解释结果的客观性和唯一性。

When the pumping wireline formation test technology is used for evaluating the oil and gas resources in the oilfield,the optimization method of key test point picking and best test plot choosing is a primary link in ensuring the authenticity and reliability of the interpretation results.Based on the advantages that pumping wireline formation tester is able to provide many kinds of formation fluid test data and instrument control parameters and started from the permeability interpretation principle of wireline formation test,this paper studied 512 groups practical testing plots of formation pressure test and sampling operation of one offshore oilfield,built up a new optimization method to accurately determine the seven key test points,such as the start point of drawdown test and the best test plot by utilizing several kinds of test information simultaneously.The developed software in this method has been applied to interpret the permeability of 109 layers combined with the test data of new domestic pumping wireline formation tester（ERCT）.The results show that the new method presented in this paper not only improves the calculation precision,but also eliminates the differences of the interpretation results caused by different operators,which ensures the objectiveness and uniqueness of the results.