pre_v_post1 pre_v_post2

Pre versus Post-Drill Stress Costs

The stress map (top left) comprises averaged SHD’s and SHM’s from breakouts from many more than 7 wells. The data took a few years to gather at the cost of millions of dollars in rig time and logging (lower left). The wells provided a series of 2D sets of data and no way to connect them in 3D except by averaging SHD’s between wells and drilling more wells.


The stress map (top right) was made 10 years ago as a trial of the PSI stress from seismic method. It used a line spacing of 6 miles (for detailed work, PSI now uses a 100 to 200m line spacing in 4DGeoStress). The SHD’s derived from the wells were reproduced and linked using the fault strike and throw information from the SHMagnitudes (SHM’s) or stress states. These stress states are compatible with data now modeled for the area.


The seismically derived full stress data (top right) were of minimal cost and ready pre-drill (lower right). PSI’s stress from seismic is clearly better, less costly and more timely for development drilling than expensive, time consuming, point source wellbore breakout data (bottom left).