I was digging around in my files, looking for something else, and I came across this copy of a letter I sent to a friend two days after Giant Geyser erupted in 1986. Since I wrote it while the memories were fresh, I figure it might be interesting. The photos posted here were taken by George Strasser (Paul's brother), who not only had a camera, but remembered to use it.
On 20 August at 1136, Giant erupted. I was at Daisy for the start, and had just passed Giant five minutes earlier. At that time, it looked like it has all summer, fairly dead. So I get to Daisy, see that Splendid's markers are in place (it had four eruptions the next day), and start to unload my pack. Then I looked over at Daisy, and saw this huge steam cloud rise above the trees.
Paul Strasser, John Railey and I have been using CB radios to keep in touch. They have been useful, but this time they paid for themselves. I grabbed the radio as I was running down the boardwalk and yelled into it, "Paul, something's erupting in the Giant Group!" He had just turned his on, and heard the "erupting in the Giant Group" part from the Lodge Cabins. He and Suzanne were down there in twelve minutes. Several other people saw the steamcloud from the VC, Lower Ham's store, or from Fantail (Biscuit Basin) and assumed either Grand or Oblong. They didn't see it.
[Paul and Suzanne were about to head out with the family of his brother George, "to look for animals", when the call came. The family was abandoned, allowing George to walk out on his own. Fortunately, he took the only series of photos of this eruption that I know about.]
Talked with some people there at the start, and they said that the sputs started maybe 30 seconds before Giant, and Mastiff was erupting only three to four feet high, but overflowing. When it started, Giant sent out a wall of water, running over the south end of the "T" boardwalk. They were afraid of scalded feet.
As I ran around the trees, I could see the water column still climbing. Mastiff was steaming and splashing heavily, while Catfish was sending a thin angled spray to 25 feet. Bijou was steaming only, and the others quickly followed. I took a short cut, and was quite pleased with events.
Giant was now near maximum height, which I estimated [measured?] to be between 150 and 180 feet (~165'). Two night before Sam Martinez and I were going to lay out a baseline, but decided not to since we would never get a chance to use it. [I think I told Sam: "It'll get stolen before we can use it."] The water column was thick, a lot like Ol' Filthy in that sense only. It also pulses, like Beehive, so it doesn't stay at max height, but drops to about 80', then surges back up. The water seemed clear, and the weather was excellent. Clear sky, dead calm but a bit humid. Paul said the steam cloud had to be several thousand feet high. Earlier that day was a thick fog, and later it rained.
By the time Paul and Suzanne arrived, surges were still in the 120' range, but the power had definitely diminished, Originally the water column appeared vertical, now it began to angle to the west slightly. It also sent spray toward the boardwalk. But on the whole, it looked exactly like the old photos.
A half hour later, Giant was still hitting 50', but there was little runoff. By now several sputs were erupting on the platform. They looked like little Uncertains, but only ~4' high. They also surged at the same time as Giant.
By 1227, Giant was mostly steam, and all steam by 1236. Grotto was not erupting all this time.
This was a strange eruption for coincidences. Not just Sam and I at the baseline. The day before at Splendid (no eruptions) T.Scott commented that he didn't have his camera, and if Giant erupted, he would kill himself.
South Purple pool had had several heavy surges of water earlier this year, and now was down below overflow. Later Grotto had some sort of steam phase, or minor eruption. The sputs between it and Rocket were erupting, but Rocket and Grotto made lots of noise and occasionally splashed. The next "real" Grotto [eruption] did not have an eruption of Grotto Fountain [preceding it].
Oblong has been weird this year, with intervals from 32 minutes(!) to 24 hours. Most intervals seem to tend toward 20 hours. Now it had three eruptions in a three hour period, with one interval of 37 minutes. These closing eruptions of a short interval are strange. The water is ejected from an empty pool, and some jets [from the north side] reach the river. They area also very noisy.
It took Bijou about 24 hours to recover, but the next day, the group looked as good, if not better, than it had all year. Now I'm hoping for an interval of less than a year. Say this coming March.
That night, we measured out the distance markers for Giant. Holding one end of the tape over Giant's vent, knowing that it couldn't erupt, was a scary experience.
In the previous thirty years, there had been only four known eruptions of Giant— in 1963, 1978, 1982 and 1984. It's been twenty four years since the last known eruption of Splendid...