Vault Geyser is located near Giantess Geyser in the Upper Geyser Basin of Yellowstone. Vault usually erupts about 4 to 8 hours after a Giantess eruption. As Vault starts its initial eruption it fills accompanied by thumps that you can hear and feel. The water rocks and bounces until the start of the eruption.

Vault Geyser, Initial Eruption, September 2001:

Vault movie (2.9 Mb, 31 sec, sound)

Image copyright 2001, George and Sue Schroeder. All rights reserved.