In 2015, an underwater volcano erupted deep off the coast of Oregon. 1,500 meters (5,000 feet) Cracks opened in the seafloor and molten lava poured out. The lava crust quickly solidified upon contact with the frigid water, but the molten lava continued to flow underneath. Eventually, the flow burst through the hardened crust, draining downhill in a fast-flowing lava "highway," and leaving behind spectacular features on the seafloor. The hollow roofs and pillars of these drainback features may be coated with colorful clays as they cool, and serve as useful perches. MBARI