LOWER GEYSER BASIN

In !997 after being dormant since 1985 Imperial started erupting from a side vent with in the the large pool  shown in the picture above.. Descriptions of these eruptions are mentioned below.  I visited the geyser in August that year and photographed 10 to 20 foot burst from the side vent. I returned in 2000 to find smaller burst of up to 10 feet.

-- On June 8, 1997 geyser gazer, Paul Strasser, reported "Imperial was observed erupting from a side pool, essentially continuously to a height of 10-15 meters." These 30 to 40 foot eruptions mark activity in a satellite vent. On her visit to the geyser on June 11 Ann Deutch made these observations "The old main vent is quiet and covered with a quiet overflowing pool. There were what looked like a series of vents on the east side of the pool. At least one of the vents was bubbling. The northernmost vent is surrounded by a low geyserite rim and was erupting the whole time it was observed to a maximum of about 15 meters. The water column is a splash style burst about 5 meters wide. The activity fluctuated but never stopped as we watched. It did not have a separate runoff channel but mingled its water with the pool. There was no evidence of recent extra flow in the overflow channel nor was the flow apparently changed from our previous visits. Watching the steam column as we left the area, we did not see any increase or diminishing of steam. This column has been visible from the main road in fountain flats at every observation this spring."

In comments about the new eruptions Scott Bryan on June 14 said "As noted in my book, Imperial prior to 1985 often had an intermittent activity, usually with both intervals and durations of less than 60 seconds. Often both factors, especially the intervals, were far shorter than that. And all this simply could "merge" into activity in which it simply was not clear if it was really pausing or not, so that it was best called a "variable perpetual spouter" or some such . In my opinion, this was actually the most common sort of action in the early 1980s.

Whether intermittent or steady, active or inactive, I've never been able to discern any significant variation in the runoff volume."

On June 20, 1997 Rocco Paperillo reported on the geyser mailing list that "Imperial ("satellite vent") is... active. Massive perpetual bursting to about 20 or more feet with spikes occasionally to 40 - 50 feet.