USGS National Assessment of Oil and Gas Project - Shale Gas Assessment Units

Publication Date

2021-06-17

Time Period

2012

Release Date

2013

Biewick, L.R., 2013, USGS National Assessment of Oil and Gas Project - Shale Gas Assessment Units: U.S. Geological Survey data release, https://doi.org/10.5066/P9C8XL9T.

The Assessment Unit (AU) is the fundamental unit used in the National Assessment of Oil and Gas Project for the estimation of undiscovered oil and gas resources. The AU is defined within the context of the higher-level Total Petroleum System. The AU is shown here as a geographic boundary interpreted, defined, and mapped by the geologist responsible for the province and incorporates a set of known or postulated oil and (or) gas accumulations sharing similar geologic, geographic, and temporal properties within the Total Petroleum System, such as source rock, timing, migration pathways, trapping mechanism, and hydrocarbon type. The AU boundary is defined geologically as the limits of reservoir rock, geologic structures, source rock, and seal lithologies. The only exceptions to this are AUs that border the Federal-State water boundary. In these cases, the Federal-State water boundary forms part of the Assessment Unit boundary.

• Energy Resources Program