Overview
This lecture describes a 2015 underwater volcanic eruption off the Oregon coast, focusing on lava flow processes and the resulting seafloor features.
Volcanic Eruption Events
- In 2015, an underwater volcano erupted 1,500 meters (5,000 feet) below the surface off Oregon's coast.
- The eruption created cracks in the seafloor, allowing molten lava to escape.
Lava Flow Dynamics
- Lava crust hardened quickly upon contact with cold seawater.
- Molten lava kept flowing beneath the solidified crust.
- The flow eventually broke through the hardened top, draining downwards as a fast-moving lava "highway."
Seafloor Features Formed
- The lava flows left hollow drainback features with roofs and pillars behind.
- As these features cooled, they became coated with colorful clays.
- These structures can serve as perches for marine life.
Key Terms & Definitions
- Underwater volcano — A volcano located beneath the ocean's surface.
- Lava crust — The quickly solidified outer layer of lava in contact with seawater.
- Drainback features — Hollow structures left when lava drains away, leaving hardened roofs and pillars.
Action Items / Next Steps
- Review the stages of underwater lava flow and seafloor feature formation.