Testing of a field technique to measure fracture aperture in situ by DNAPL surrogate injection

摘要

A new technique to measure fracture aperture in the field by injection of a DNAPL surrogate is described. The method employs a double packer array to hydraulically isolate fractures in a cored borehole, through which a relatively harmless NAPL (vegetable oil) is injected. Fracture aperture is derived from reverse modelling of the capillary pressure data using a two-phase flow numerical model. Hydraulic aperture results from slug tests in a double-packer setup range from 20 μm to 180 μm in fractured Permian breccia, and these will be compared to apertures derived from the NAPL injection experiment.