Seismic Attributes for Fault/Fracture Characterization

Satinder Chopra¹ and Kurt J. Marfurt^2
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