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Gas pistons within the Drainhole vent at Pu‘u ‘Ō‘ō

(June 2, 2006, 18:30:02 to June 3, 2006, 02:00:03) Gas-pistoning is an interesting phenomenon seen at Kīlauea and some other basaltic volcanoes. It is caused by the accumulation of gas near the top of the lava column within a volcanic vent (Swanson and others, 1979). The shallow accumulation of gas causes the lava surface to rise (the "piston"). Eventually, the gas breaches the surface and escapes, typically as a forceful jet of fume and spatter. The lava then drains back into the vent. Gas pistons can occur as single events or as a repeating series comprising dozens or even hundreds of events. During mid-2006, eruptive activity at the informally named "Drainhole" vent, on the floor of the Pu‘u ‘Ō‘ō crater, was often characterized by periods of gas-pistoning. This movie sequence is an example of the gas pistons that were occurring at that time. The images that make up this movie were acquired by a time-lapse camera positioned on the northern rim of the pit that hosted the "Drainhole" vent. The opening in the pit floor is about 5 meters across. Movie Details: File size = 96.1 MB Image interval = 1 minute Playback speed = 10 frames/sec Movie duration = 00:00:45 Camera Coordinates (WGS84): Lat: 19.3886º Long: -155.1060º View direction = ~186º