致密油藏储量升级潜力不确定性评价方法及应用

中国陆相致密油藏储量升级评价面临着储层非均质性强、阶段地质认识不确定性大和静、动态评价结果差异明显等一系列难题,使用常规确定性评价方法存在一定局限性.为此,建立一套系统的储量升级潜力不确定性评价方法,重点实现3方面改进:①以不确定性储量评价方法代替传统确定性方法,定量地给出不同可靠程度下的可升级储量;②基于后验概率思想...

Non-deterministic method for tight oil reserves upgrade potential assessment and its application

Reserves upgrade potential assessment of continental tight oil reservoirs in China encounters a series of problems such as high reservoir heterogeneity, great uncertainties caused by limited geological understanding of certain stages, and marked differences between static and dynamic evaluation results.All these are difficult to be dealt with conventional deterministic methods.Therefore, a systematic non-determinstic reserves upgrade potential assessment method was proposed.The method is an improved version in terms of the following three aspects.Firstly, with uncertainties considered, the reserves with upgrading potential are quantitatively determined under diverse reliabilities.Secondly, a mutual correction and comprehensive evaluation of the static and dynamic methods is made possible by applying the posteriori probability theory.Thirdly, reserves upgrade probabilities and scales are quantitatively evaluated based on probability method by introducing the concept of upgrade probability.The reserves upgrade probability and scale under different oil prices and engineering technology conditions were clearly seen when applying the method to the possibility assessment of upgrading 'controlled reserves' to a higher reserves category for tight oil reservoirs in the Chang 8 Member of Well Block A, Ordos Basin.This shows that the method could be of effective technical support to tight oil reserves upgrade evaluation and exploration target optimization in China.