AAPG Methods in Exploration No. 13, Chapter 16: Wellbore
Imaging Technologies Applied to Reservoir Geomechanics and Environmental Engineering , by Colleen
A. Barton and Mark D. Zoback, Pages 229 - 239
from:
AAPG Methods in Exploration No. 13: Geological Applications of Well Logs, Edited
by M. Lovell and N. Parkinson
Copyright © 2002 by The American Association of Petroleum Geologists. All rights
reserved.
Chapter 16
Wellbore Imaging Technologies Applied to Reservoir Geomechanics and Environmental
Engineering
Colleen A. Barton
GeoMechanics International, Inc.
Palo Alto, California, U.S.A.
Mark D. Zoback
Stanford University
Department of Geophysics
Stanford, California, U.S.A.
ABSTRACT
Drilling-induced wellbore failures provide critical constraints on the in-situ state of
stress. Knowledge of the relationship between natural fracture systems and tectonic
stresses has direct application to problems of reservoir performance, fluid migration, and
wellbore stability. Acoustic, electrical, and optical wellbore images provide the means to
detect and characterize natural fracture systems and to discriminate these from induced
wellbore failures. New techniques of wellbore-image analysis are presented to distinguish
attributes of natural fractures from induced failures in borehole-image data. The
performance of low-permeability fractured reservoirs is controlled by the in-situ state of
stress and by the distribution and orientation of natural fractures and faults. We discuss
case studies of the relationships among natural fracture systems, in-situ stress, and
permeability. These case studies involve geothermal reservoirs and a petroleum reservoir;
one case study involves geotechnical site characterization.