Seismic
Attributes for Fault/Fracture Characterization
Satinder Chopra1 and Kurt J. Marfurt2
1Arcis Corporation, Calgary, AB, Canada
2University of Oklahoma, Norman, OK
Among the various geophysical techniques available for characterizing faults and fractures, 3D seismic
attributes are particularly useful for identifying faults, large fractures, or fracture zones. To be useful,
seismic
attributes derived from 3D
seismic
volumes need to be sensitive to a desired geologic feature or a reservoir property of interest. This search has led to the development of more and more
seismic
attributes, with the result that there are a few hundred
seismic
attributes that are known, many of which are widely used for lithological and petrophysical prediction of reservoir properties. Of these various attributes, dip-magnitude, dip-azimuth and coherence attributes have been used for the detection of faults and fractures. We will also demonstrate how curvature attributes are specially suited for determining the geometry of such features.
There are many ways to bring out these features of interest in 3D seismic
attribute
volumes, some subtle and some prominent. Apart from the choice of the computation parameters, conditioning of the input data, and the choice of
attribute
algorithms make a significant difference to the quality of the results. In this presentation, we will discuss advantages of volumetric curvature applications in preference to horizon-based curvature. We find that most-positive and most-negative curvature attributes facilitate a better interpretation of fault/fracture detail than other attributes. Furthermore, by picking lineaments seen in the most-positive and most-negative curvature displays, we can generate rose diagrams, which when compared with corresponding diagrams from image logs, lend confidence in the performed interpretation.
AAPG Search and Discovery Article #90078©2008 AAPG Annual Convention, San Antonio, Texas