On demand viewing of our current and past lecture videos can be found here. You can also view videos (2012 - current) via our Public Lecture Series playlist on our USGS YouTube channel.
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.
