Geophysical Terranes of the Great Basin and Parts of Surrounding Provinces

This study of geophysical terranes within and surrounding the Great Basin of
the western United States integrates geophysical and geologic data to
provide new insights on basement composition and structure at local,
intermediate, and regional scales. Potential field (gravity and magnetic)
studies are particularly useful to define the location, depth, and extent of
buried basement sources and fundamental structural or compositional boundaries.
They especially serve in imaging the subsurface in areas of extensive Cenozoic
cover or where surface outcrops may be detached from the deeper crust.
Identifying buried compositional or structural boundaries has applications, for
example, in tectonic and earthquake hazard studies as they may reflect unmapped
or buried faults. In many places, such features act as guides or barriers to
fluid or magma flow or form favorable environments for mineralization and are
therefore important to mineral, groundwater, and geothermal studies. This work
serves in assessing the potential for undiscovered mineral deposits and
provides important long-term land-use planning information. The primary
component of this report is a set of geophysical maps with anomalies that are
labeled and keyed to tables containing information on the anomaly and its
source. Maps and data tables are provided in a variety of formats (tab
delimited text, Microsoft Excel, PDF, and ArcGIS) for readers to review and
download. The PDF formatted product allows the user to easily move between
features on the maps and their entries in the tables, and vice-versa.

[Summary provided by the USGS.]