2017-04-05. Balloons of Lava Bubble into the Ocean from Seafloor Blisters.

posted Apr 8, 2017, 7:55 AM by Alan Gould
By Lauren Lipuma, Earth & Space News, AGU. For GSS Energy Flow chapter 3. Excerpt: These peculiar features of submarine volcanic eruptions could be the result of undersea lava lakes. Imagine that you’re a fisherman at sea and suddenly your boat is surrounded by dozens of floating pieces of hot, dark rock, hissing and spewing vapor. Some rocks are no bigger than footballs, and some are larger than refrigerators. But just a few minutes later, the mysterious chunks sink below the surface without any hint of where they came from. That is exactly what happened to a group of fishermen in the Azores, Portugal, in late 1998. It turns out they were witnessing the appearance of lava balloons: floating lumps of hollow, cooled lava burped up from the seafloor after an undersea volcanic eruption. The fishermen described the balloons as “hot steaming stones whose high temperature caused minor damage to the fishing ropes,” with “fire coming out from the seawater spreading on the air like sparks of fireworks,”.... The balloons are a strange and rare phenomenon, but they also serve a scientific purpose: They alert researchers to underwater eruptions that might otherwise go unnoticed, said Ulrich Küppers, a volcanologist at the University of Munich. ...He suspects they are the result of trapped magmatic gas pushing upward through lava during some kinds of undersea eruptions. Küppers presented his theory at the recent AGU Chapman Conference on submarine volcanism in Hobart, Tasmania....  https://eos.org/articles/balloons-of-lava-bubble-into-the-ocean-from-seafloor-blisters