Workflows

UT Centroid

We have developed an approach to predict reservoir pressure as a function of reservoir geometry and mudstone permeability (Fig. 3). This workflow is encapsulated in an online software that is freely available to UTGeoFluids members and several member companies are negotiating formal access to the approach.

Seismic Pressure Prediction Integrated with Geomechanical Modeling

We have invented a workflow that integrates seismic velocity data with geomechanical modeling to predict pressure and the full stress tensor (Fig. 2) (Heidari et al). Our method incoporates the role of mean and shear stress in pressure and stress prediction and take into account complex stress states found in basins. The method represents a fundamental advance from vertical effective stress (VES) models and can be systematically incorporated into pore pressure and stress workflows.

Wellbore HF Model

UT GeoFluids has developed an analytical well bore stability tool (UT-FracModes) (Fig. 2a) to calculate fracture pressures in vertical wellbores. It considers both tensile and shear modes of hydraulic fracturing, and both induced and natural fractures or faults. We calculate both fracture initiation pressure, based on the near-wellbore stresses, and fracture extension pressure, based on far-field stresses. We also developed a 3D finite-element code (Fig. 2b) to calculate the width of a fracture with any given orientation as it opens during a circulation loss event. These tools provide solutions needed for preventing and mitigating circulation losses.

UT-FAST-P3

UT-FAST-P3 allows users to predict and compare pore pressure using the full stress tensor. It is an educational tool that illuminates why it is important to go beyond vertical effective stress (VES) models. Users input a measured velocity and overburden, a velocity-effective stress calibration and a frictional strength. The output is pore pressure from 3 methods:  1) vertical effective stress (VES), 2) mean effective stress (MES), and 3) the full stress tensor (FES). UT-FAST-P3 demonstrates the relative contribution of mean and deviatoric (shear) stress to pore pressure (Fig. 3); it is available to all consortium members through this link.