Scientists have recorded the deepest erupting undersea volcano ever seen, capturing for the first time video of fiery molten lava bubbles exploding 4,000 feet beneath the Pacific Ocean. A submersible robot witnessed the eruption in May during an underwater expedition near Samoa, and the high-definition videos were presented Thursday at a geophysics conference in San Francisco. Scientists hope the images, data and samples obtained during the mission will shed new light on how the earth's crust was formed. The research could also help explain how some sea creatures survive and thrive in extreme environments and how the earth behaves when tectonic plates collide. “It was an underwater Fourth of July,” said Bob Embley, a marine geologist for the National Oceanic and Atmospheric Administration, in a news release. “Since the water pressure at that depth suppresses the violence of the volcano's explosions, we could get the underwater robot within feet of the active eruption.” The eruption was a spectacular sight: Bright-red lava bubbles shot out of the volcano, releasing a smoke-like cloud of sulfur. The lava froze almost instantly as it hit the cold sea water, causing black rock to sink to the sea floor. The submersible hovered near the blasts, its robotic arm reaching into the lava to collect samples. Earth and ocean scientists said the eruption allowed them to see for the first time the creation of a material called boninite, which had previously been found only in samples at least a million years old. The mission to record a deep-sea volcanic eruption was 25 years in the making. Although 80 percent of the earth's volcanic activity occurs in the sea, scientists from NOAA and the National Science Foundation had never witnessed an eruption this deep and in this detail.
