Global Volcanism Program | Image GVP-10019
During a submarine eruption first observed on January 29, 1993, small explosions were produced as floating hot rocks fractured and their hot interiors came in contact with sea water. Large blocks of dark-gray, highly-vesiculated basalt up to 5 m in diameter rose to the surface. During individual pulses at irregular intervals, tens of blocks accompanied by effervescent bubbles could be observed rising buoyantly. The blocks emitted loud hissing and crackling noises from thermal expansion prior to breaking up into smaller pieces and sinking.
Photo by Hugo Delgado-Granados, 1993 (Universidad Nacional Autónoma de México).