Contiguous United States Earth Model in 3-D: Application to Regional Screening of Unconventional Plays

We present a 3D Earth Model of the contiguous United States and demonstrate its use for the rapid assessment of unconventional play potential, with examples from several shale gas and shale oil plays. The model encompasses all strata from basement to surface, and covers the entire contiguous states. Based on our robust sequence stratigraphic framework and a database of publically available information, the model is divided into 82 layers corresponding to key 1st, 2nd and 3rd order depositional sequences.

Regional play evaluations demand the integration of large volumes of geoscience data and interpretations from a wide variety of sources, including wells, seismic, facies maps, structure maps, geochemistry data and basin modelling. Historically a task for an experienced explorer and a light table, the advent of geographical information systems (GIS) allows greater efficiencies and some automation of workflows, but still does not offer complete integration of data, applications and products.

Recent advances in computer hardware and software, in particular Petrel 2011* from Schlumberger Information Solutions, enables us to build 3D geological models at a scale appropriate for regional exploration. Petrel 2011 and related software allow us to load and manipulate all the data required to carry out play evaluations, and offers an environment where all data and interpretations are fully integrated. The resulting models then allow the user to visualise geoscience information in both the depth and geological time domains. This not only improves efficiencies, but adds increased insight into the geological basis for petroleum system and play fairway analysis.

The resulting contiguous United States Earth Model allows us to identify and visualise the extent of key shale horizons, gain a greater understanding of their stratigraphic setting, and place them in their wider geological context. Furthermore, the addition of geochemical data to the model enables us to apply geochemical screening parameters and rapidly assess their potential. Common risk segment maps can then be compiled for each play and highlight areas of increased prospectivity.

AAPG Search and Discovery Article #90142 © 2012 AAPG Annual Convention and Exhibition, April 22-25, 2012, Long Beach, California