ABSTRACT: A technique was developed for measuring shale pore pressure change caused by simultaneous hydraulic and chemical forces, using preserved shales under simulated in situ conditions. It was found that chemical forces can offset hydraulic forces and can maintain shale pore pressure at a value different than the applied fluid pressure. The influence of shale type, salt type and salt concentration on this pressure difference were investigated. The observed pressure differences are compared with the predictions of osmotic theory, and membrane efficiencies are calculated. Shale permeability is also determined from the test data.

This content is only available via PDF.
You can access this article if you purchase or spend a download.