On the Characterization of the Viscoelastic Response of the Vaca Muerta Formation.

The time dependent behavior of a reservoir rock is of outmost importance on the understanding of wellbore stability during drilling and also the long term productivity of a fractured well. For these reasons, the aim of this work is the derivation of a general constitutive model which should capture the creep behavior of Vaca Muerta formation. To achieve this goal, many time cycling triaxial deformation creep tests were performed over many Vaca Muerta rock samples. A phenomenological creep constitutive model from the literature such as the Power Law was tested and evaluated to find the best fit from the data acquired from laboratory testing. Finally, the creep behavior of Vaca Muerta formation is compared briefly with published data from U.S. shales.