# Analysis Regions

Polygons that define regions over which comparative NSHM rate model analyses are performed. The
total extent of these regions is roughly equivalent to the area over which the NSHMP generates
maps for the Conterminous U.S., but not an exact match on the west and southwest margins.

In the Western U.S., these regions include:

- The region that was used during the development of UCERF2 and UCERF3.
- A Pacific Northwest region.
- An Intermountain West region. The Intermountain West region is further subdivided along the
  updated (2022) attenuation boundary across which there are significant differences earthquake
  rate and geologic/tectonic properties.

Created by: @pmpowers 11/3/2022
Filename and title updates: 11/22/2022
