Abstract
In this study a series of synthetic clays and unconsolidated sands of different textural and mineralogical compositions have been tested using triaxial cell under uniaxial (one-dimensional) strain conditions applying high effective vertical stresses (up to 30-50 MPa). A highly specialized setup with combined measurements of axial and radial deformation, acoustic velocity and hydraulic properties was developed to achieve the test program. Results from tests show that the constrained modulus, K0, acoustic velocity and permeability anisotropy versus effective stress relationships were dependent on the mineralogical and textural compositions of rocks. These data are valuable input for parametric studies and uncertainty analysis of shallow reservoirs in general and especially when there is lack of site specific data. For areas with more detailed knowledge of mineralogical and textural compositions more exact predictions can be made and uncertainty span can be reduced. Examples of applications towards compaction and fracturing evaluations are given and the effect of drainage of clay units on the overall compaction is also demonstrated in case of a complex reservoir.