低渗储层应力敏感评价方法探讨

PROBE INTO EVALUATION METHODS FOR STRESS SENSITIVITY OF LOW PERMEABILITY RESERVOIRS

应力敏感评价是储层保护以及油气井产能评价的重要依据,尤其对低渗储层更显意义重大。目前国内对油气储层的应力敏感评价方法及标准尚存在争议,通过对国内外曾提出的应力敏感评价标准进行研究,探讨了现行行业标准中存在的不足以及传统理论研究所采用的渗透率模量概念存在的局限性。在大量实验数据分析的基础上,定义了新的应力敏感评价指标,可以方便地表征任意初始渗透率随有效覆压变化的关系,对油气井产能评价以及建立低渗变形介质油气藏渗流模型具有积极意义。

Stress sensitivity Evaluation is important to formation damage control and determination of reasonable well productivity,especially for low permeability reservoirs,currently,there are much argument on evaluation methods and standards of stress sensitivity in China.By research of foreign and domestic standards,the disadvantages of domestic industrial standard and the limitation of permeability modulus used in theoretical research are discussed.Based on analysis of plenty of experimental data,a new stress sensitive index is defined,with which,the relationship of initial permeability and effective stress can be expressed conveniently,which is significant to productivity evaluation of oil & gas well and establishment of model of flow through porous media for low permeability reservoirs.