3D seismic attributes analysis to outline channel facies and reveal heterogeneous reservoir stratigraphy; Weirman Field, Ness County, Kansas, USA

Abstract

This research presents a workflow integrating several post-stack seismic attributes to assist in understanding the development history of Weirman Field, Ness County, KS. This study contributes to shaping future drilling plans by establishing a workflow combining analysis of seismic attributes and well cuttings to locate a channel fill zone of better reservoir quality, and to highlight reservoir boundaries due to compartmentalization. In this study, I have successfully outlined a fluvial channel, which is expected to be significantly different in terms of petrophysical properties. The Pennsylvanian aged Cherokee sandstones that potentially comprise channel fill lithofacies, in this study, have been linked to oil production throughout the state of Kansas. It is important to understand channel sandstones when evaluating drilling prospects, because of their potential as an oil reservoir and unpredictable shapes and locations. Since their introduction in the 1970s, seismic attributes have become an essential part of lithological and petrophysical characterization of hydrocarbon reservoirs. Seismic attributes can correlate to and help reveal certain subsurface characteristics and specific geobodies that cannot be distinguished otherwise. Extracting and analyzing acoustic impedance, root-mean-square amplitude and amplitude attenuation, guided by a time window focused on the top of the Mississippian formation, resulted in an understanding of the key seismic channel-facies framework and helped to explain some of the disappointing drilling results at Weirman Field. To form a better understanding of these seismic attributes, this study combined certain attributes and overlayed them in partially transparent states in order to summarize and better visualize the resulting data. A preliminary study of spectral decomposition, which was introduced in the late 1990s, was preformed, and a more in-depth study of this multi-resolution attribute is recommended for future study of this particular field. This study also recommends integrating the revealed compartmentalization boundary and the seismic channel-facies framework in future drilling plans of Weirman Field.