SEISMIC ATTRIBUTE ANALYSIS OF UNCONVENTIONAL RESERVOIRS, AND STRATIGRAPHIC PATTERNS

Abstract

Seismic volumetric attributes have become one of the key components in aiding interpretation and investigation of the hydrocarbon reservoirs. These reservoirs can be either conventional or unconventional. The application of seismic attributes in conventional reservoirs with mapping bright spots, faults, and channels has been quite successful. Now we face challenges in mapping unconventional reservoirs such as shales, tight gas sands, and carbonates as well as igneous reservoir. This dissertation focuses on developing new workflows to map unconventional reservoirs in a qualitative or quantitative fashion using seismic attributes. The unconventional reservoirs under study include shales, carbonates and volcanic build-ups.

A common challenge with many unconventional reservoirs is that they have low permeability, such that fractures are critical to economic success. I apply a different workflow measuring azimuthal anisotropy in the Barnett Shale of the Fort Worth Basin after hydraulic fracturing. The resulting anisotropy is not only heterogeneous, but compartmentalized by previous (Pennsylvanian) deformation. I also develop a workflow to correlate production with proximity of the well to curvature lineaments by scanning hypothesized open fractures as a function of azimuth. I calibrate this workflow to a previously studied Mississippian limestone reservoir from Kansas prior to application to the Woodford Shale of the Arkoma Basin. My final study is a volcanic extrusive reservoir from the Songliao Basin, Northeast China. Volcanic are usually avoided, while I hope that this example may serve as an analogue for others.

As part of my analysis, I also document the extension of the previous workflow and development of new algorithm related to spectral-decomposition.