Preparation of the saturating water for sample GB13
Water chemically equilibrated with sample GB13 was prepared and injected
as follows: For several weeks before saturation, we submerged a few
grams of GB13 granules in deionized water. Then, the injection of such
aqueous fluid was performed using a high-pressure syringe pump (ISCO
260HP), recording – via a Matlab script - the injected volume and
injection pressure. The latter was maintained constant to a value of 3
MPa lower than the confining pressure that varied between 20 and 50 MPa.