摘要
多数低渗致密砂岩气藏储层岩石孔隙含水，其赋存状态及可动性对于致密砂岩储层渗流特征和气井生产动态的影响非常大。本文综合利用测井解释、核磁共振、岩心实验等多项技术，建立了一套致密砂岩储层孔隙水可动性评价方法和流程。以苏里格气田为例，研究了储层岩石孔隙原始含水在不同孔隙结构中的赋存模式以及气藏开发过程中随气驱压差增加，储层孔隙水的可动条件、动态变化过程。结果表明：经过长期成藏作用后，储层岩石孔隙水以不同模式赋存于各类孔隙中并处于平衡状态（即束缚水），在气藏发过程中随着储层孔隙压力下降，气水平衡条件被打破，在膨胀能和气驱压力共同作用下，连通孔隙内的束缚水部分会转变为可动水并在渗流通道上两者（可动水、束缚水）交互变化。因此，对于致密砂岩气藏开发来说，储层岩石孔隙水的可动性是不可回避的一个关键问题。
The mobility and occurrence state of water in the pore of gas formation is one of the important factors affecting the gas production. By means of multiple methods such as log interpretation, NMR and gas drive water experiments, in this paper a set of evaluation and procedure has been established on the mobility of the water in the pore of gas formation, and a case study on Sulige gas field is also investigated to analyze the occurrence state of original water in the pore with different structures, and the moveable condition as well as changing trend, and to reveal that the moveable water increased with the pressure under gas field development. The result indicates that after long time accumulation, the water with varying occurrence states in the kinds of pores is in balance, namely, bound water; while in the course of gas development, with the decline of reservoir pore pressure and the imbalance of gas and water, suffering from both the dilatation energy and the pressure driven by gas, the bound water connecting pores will be transformed to movable water, and on the permeable channel, the both water are in alternation. Therefore, with respect to the tight gas sandstone development, the mobility of pore water in reservoir rock is the key issue that can＇t be avoided.
关键词
致密砂岩气
气层孔隙水
可动水
评价方法
Tight gas Sandstone
Water in the Pore of Gas Formation
Movable Water
Evaluation Method
