This picture shows an eruption of Clepsydra Geyser. Clepsydra erupts almost continuously. In fact, unlike other geysers in the park, the park rangers don't keep data on Clepsydra's eruptions but instead they keep data on the times that it stops. Currently, the best show in the area is put on by Fountain Geyser.

This picture is from the Jackson Hole Yellowstone Park Page.