An official website of the United States government. Here's how you knowHere's how you know
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.
Latest Earthquake | Chat Share
The USGS Alert-Notification System for Volcanic Activity includes Volcano Alert Levels, which rank a volcano’s status for people on the ground, and Aviation Color Codes, which rank airborne ash hazards for the aviation sector. This four-tiered system ranges from Normal/Green to Warning/Red to indicate increasing level of concern.