Application of Structural Seismic Attributes for “Polygonal Faults” Interpretation in Unconventional Carbonate Reservoir

Abstract

Seismic attributes are specific functions derived from seismic data, to enhance the appearance of different geologic features along the main seismic reflectors in both cross-section and map views. In this work we applied volume seismic attributes in order to enhance the appearance of the polygonal faults located at the Abu El-Gharadig basin, North of Western Desert, Egypt. The main objective is to illuminate the small or sub-seismic faults to determine its implication on the unconventional carbonate reservoir, of the Middle Eocene Apollonia Formation. The workflow started by the application of the structural smoothing attribute on a 3D post-stack, depth migrated seismic volume, in order to highlight the discontinuities of the seismic reflectors along the seismic sections. This is followed by the calculation of two main attributes, seismic coherence and curvature attributes. The most positive and most negative curvature attributes allowed us to identify small faults that are below seismic resolution. We found that the curvature attributes delineate faults distribution in our area of study better than other attributes. The presence of these faults had been verified by the geosteering technique applied during the drilling of one of the horizontal wells in the field. As a result, this study can potentially enhance the quality interpretation of seismic data and better identification of the major and minor faults that have an important implication on the fluid flow characterization of the reservoir.

AAPG Datapages/Search and Discovery Article #90355 © 2019 AAPG Africa Region, The Eastern Mediterranean Mega-Basin: New Data, New Ideas and New Opportunities, Alexandra, Egypt, September 6-7, 2019