Volumetric
Curvature-Attribute Applications for Detection of Fracture Lineaments and Their
Calibration
Chopra, Satinder1, Kurt J.
Marfurt2 (1) Arcis Corporation,
Curvature attribute applications on 3D seismic
horizon surfaces have recently been demonstrated for the prediction of
fractures. Different curvature attributes have been shown to be correlated with
open fractures measured on outcrops. These applications are limited by the
interpreter's ability to pick horizons of interest on 3D seismic data volumes.
This could be a challenging task in datasets contaminated with noise and also
in zones where the rock interfaces do not exhibit significant impedance
contrast to warrant a pickable horizon. Very recently, volumetric computation
of curvature has been introduced, which dispels the
need for horizons and provides valuable information on fractures orientation
and density in zones where horizons are not trackable. Several applications of
volume curvature have been completed in different geological settings,
that define small scale faults, isolate highly fractured zones and also
relate such fractures to spatial variation of strain.
While a direct prediction of open
fractures using curvature attributes requires a significant amount of
calibration through the use of production, tracer, image logs or microseismic
measurements, volumetric curvature attribute analysis serves as a powerful aid
to stratigraphic interpretation. Such fault/fracture interpretation has been
ably supplemented with a calibration procedure with well log data, in that the
orientations of the fault/fracture lineaments interpreted on curvature displays
can be combined in the form of rose diagrams, which in turn can be compared
with similar diagrams obtained from FMI (Formation Micro-Imager) well logs to
gain confidence in calibration. Interpretation and calibration of stratigraphic
features on volume curvature displays will be demonstrated.
AAPG Search and Discover Article #90063©2007 AAPG Annual Convention, Long Beach, California