Link to USGS home page.
USGS HOME
Contact USGS

  • Assess
  • Prepare
  • Forecast
  • |
  • Activity
  • Products
  • Observatories
  • About

Mar 7, 2014: This Quicktime movie shows the lava pond in Pu‘u ‘Ō‘ō crater, which was undergoing "gas pistoning". Gas pistoning is the cyclic rise and fall of the lava surface, driven by the buildup and release of gas in the lava pond. This sequence shows the drop of the lava level, which corresponds with vigorous spattering and agitation of the pond surface.