Looking into the Halema`uma`u vent cavity

video from a thermal camera looking into the vent cavity at Halema`uma`u around 3pm today. The video is shown at x4 speed. At the beginning of the clip, the lava level is at a high stand, with slowly migrating crustal plates and little spattering. Eventually, small scale spattering begins in the northeast corner of the pond, accompanied by vigorous degassing. As the violent spattering disrupts the surface crust, the lava level falls as the gas volume is released. In this example, the lava level dropped about 30 meters (100 feet).