Rocky Mountain Section

Analog outcrops are commonly used to develop predictive reservoir models and provide quantitative parameters that describe the architecture and facies distribution of sedimentary deposits at a subseismic scale, all of which aids exploration and production strategies. The focus of this study is to create a detailed geological model that contains realistic reservoir parameters and to apply nonlinear acoustic full-waveform prestack seismic inversion to this model to investigate whether this information can be recovered and to examine which geological features can be resolved by this process.

Outcrop data from the fluviodeltaic sequence of the Book Cliffs (Utah) are used for the geological and petrophysical two-dimensional model. Eight depositional environments are populated with average petrophysical reservoir properties adopted from a North Sea field. These units are termed lithotypes here. Synthetic acoustic prestack seismic data are then generated with the help of an algorithm that includes all internal multiples and transmission effects. A nonlinear acoustic full-waveform inversion is then applied to the synthetic data, and two media parameters, compressibility (inversely related to the square of the compressional wave velocity v_P) and bulk density, ρ, are recovered at a resolution higher than the shortest wavelength in the data. This is possible because the inversion exploits the nonlinear nature of the relationship between the recorded data and the medium contrast properties. In conventional linear inversion, these details remain masked by the noise caused by the nonlinear effects in the data. Random noise added to the data is rejected by the nonlinear inversion, contributing to improved spatial resolution. The results show that the eight lithotypes can be successfully recovered at a subseismic scale and with a low degree of processing artifacts. This technique can provide a useful basis for more accurate reservoir modeling and field development planning, allowing targeting of smaller reservoir units such as distributary channels and lower shoreface sands.

The technical program is now in place and registrations are being accepted for the second annual Unconventional Resources Technology (URTeC) Conference, which will be held Aug. 25-27 at the Colorado Convention Center in Denver.

If you want to know about the Eagle Ford play in Texas, AAPG member Art Donovan is a man you want to be talking to.

Orion Skinner, senior explorationist at Whiting Petroleum, is this year’s winner of AAPG’s Norman H. Foster Outstanding Explorer Award.

Online registration is open for this year’s AAPG Annual Convention and Exhibition, which will be held April 6-9 at the George R. Brown Convention Center in Houston – and reduced registration fees are still available for those who act fast.

Energy is required to secure, treat and distribute water; conversely, energy production depends on an abundant and reliable source of water.

Every six months, chairs of the Energy Minerals Division committees convene and report on developments in the areas they cover. In this column, we highlight important observations from these recent reports.

Denver’s 20-year-old 3-D Seismic Symposium has grown into an institution by fostering camaraderie and community and by launching careers.

Seismic Outlook: After several years of plenty, 2014 is expected to be a comparatively lean year for the seismic industry, a few localized hot-spots around the world notwithstanding.

New geosteering tools are helping to drive eye-raising crude oil production levels in the Bakken shale play.