An official website of the United States government
Here’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.
This site is currently in beta, and your feedback is helping shape its ongoing development.
These data are presented to geochemically characterize glass from the informally named Khonkho tephra, an ashfall deposit that crops out at the Khonkho Wankane archaeological site in Jesus de...