Physical map of the western USA showing locations of strong earthquake

Physical map of the western USA showing locations of strong earthquakes in March 2020 and Basin and Range extensional province. The Basin and Range stretches from the Sierra Nevada in the west to the Wasatch and Teton mountains in the east, and from central Idaho and southwest Montana in the north to Mexico in the south. The M6.5 Idaho and M5.7 Utah earthquakes in March 2020 were associated with faulting in the Basin and Range. Modified from Wikipedia image.