PubTalk 9/2003 — Beneath Crater Lake

An underwater volcanic landscape tells a complex tale

by Charles R. Bacon, Geologist

Visualizations presented by David W. Ramsey, Geologist

• Crater Lake, a jewel of the National Park system, partly fills a caldera basin formed during a giant volcanic eruption 7,700 years ago
• Deepest of all U.S. lakes, Crater Lake has no surface outlet. How does its fresh water leave the lake?
• Cooperative studies by USGS, National Park Service, and university scientists have probed the lake's secrets
• New high-precision echo sounding and GPS navigation techniques "strip away" the water to reveal volcanoes, lava deltas, and giant landslides