G. Hareland et R. Harikrishnan, COMPARISON AND VERIFICATION OF ELECTRIC-LOG-DERIVED ROCK STRESSES ANDROCK STRESSES DETERMINED FROM THE MOHR FAILURE ENVELOPE, SPE formation evaluation, 11(4), 1996, pp. 219-222
This paper evaluates the correlation between values of minimum princip
al in-situ stress derived from sonic logs and those obtained from tria
xial core tests and coefficient for earth at rest correlations. The mi
nimum principal in-situ stress is then compared to actual field mini-f
rac test data, which accurately determine the minimum principal in-sit
u stress and are used to verify the accuracy of the correlations. The
cores and the mini-frac stress test were obtained from two wells, the
Gas Research Inst.'s (GRI's) Staged Field Experiment (SFE) #1 well thr
ough the Travis Peak Formation in the East Texas Basin, and the U.S. D
ept. of Energy's Multiwell Experiment (MWX) wells located west-southwe
st of the town of Rifle, Colorado, near the Rulison gas field. Results
from this study indicate that of the two approaches used in obtaining
the minimum principal in-situ stress, the normalized Mohr failure env
elope approach is in better agreement with the measured stress values
(from mini-frac tests) in sandstone, while the sonic log approach give
s closer match in shale.