Design of the Acoustic Zoom Method for Non-Specular Backscatter Imaging of the Eagle Ford Formation
The Acoustic Zoom® (AZ) Method is an unconventional oil and gas exploration technology for 3D/4D seismic imaging that offers unique resolution and direct focusing of non-specular backscatter energy returns in land and marine environments. The AZ pilot site targets the complex geology of the Eagle Ford (Shale) and it has unique geometry. The receiver array comprises of sixteen spokes (eight lines through a hub) at ∼22.5°increments. This array was deployed to intersect GGS's Wrangler 3D survey in Wilson County, Texas, over the prolific Eagle Ford, Austin Chalk, and Buda (limestone) formations. The AZ purpose-designed array—covering 12.5 km2, encompassing over 4000 receivers, and with recorded frequencies up to 170 Hz—acquired over two terabytes of data. Five vibroseis locations were established in a cross configuration at a quarter of wavelength separation. At each of the five vibroseis locations, 512 sweeps were generated and vertically stacked for a total of 2560 sweeps. This unique star-shaped dense array enables AZ to map scatterers, fractures, and diffusely reflecting boundaries via in-house AZ pre-filtering, beamforming and steering techniques.
AAPG Datapages/Search and Discovery Article #90194 © 2014 International Conference & Exhibition, Istanbul, Turkey, September 14-17, 2014