Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Cartoon showing horizontal sediments offset by two paleoearthquake fissures (red lines) that were at the ground surface at the time of each earthquake. The fissures were subsequently filled by the next layer of sediment.
Public Domain.
