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
Crystal with concentric zones, like tree rings, that was found within the Scaup Lake lava flow. This image was taken with a special microscope at Arizona State University that highlights differences in the chemistry of the different parts of the crystal.