非常规致密砂岩储层产能模拟分析——以西湖凹陷Z构造为例

An analysis of the productivity simulation for unconventional reservoirs of tight sandstone:a case from Z structure in Xihu sag

西湖凹陷西部次洼带Z构造渐新统花港组储层属于非常规致密砂岩气储层,压裂前实测产能较低,达不到工业产能。为了研究该地区不同物性储层的产能特征,选取Z构造花港组6块岩心在全模拟地层状态下进行了弹性气驱产能模拟实验,拟合得出了产能预测公式,并利用校正后的公式对该区某井花港组各储层段进行了产能预测,结果表明模拟预测产能与实测产能吻合度较高,说明实验室产能模拟值可作为无DST测试产层的无阻流量取值参考,但产能分析时需要作表皮系数校正。

As an unconventional reservoir of tight sandstone, Oligocene Huagang Formation in Z struc- ture, West sub-sag, Xihu sag, is quite low in produc- tivity and can not meet the requirements of industrial production before fracturing stimulation. In order to study the productivity in reservoirs with various petro- physical properties in this area, 6 core samples were selected in Huagang Formation, Z structure, for a productivity simulation experiment by elastic gas driv- ing under the simulated formation condition, in which a prediction formula was developed by fitting. After correcting the formula, it was used to predicted the productivity for each reservoir interval in Huagang Formation in a well, and it can be found that the pre- dicted productivity coincides well with the actual test productivity. This result may indicate that the simula- ted values of productivity can be used as a reference for setting the values of open-flow capacity in a reservoir without DST, but it is needed to make the skin factor correction when analyzing the productivity.