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Link Geyser, 1983


Here's a series of photos showing some of the activity of Link Geyser and the Chain Lakes Group during the activity in October 1983. Over a period of five days, Mary Ann Moss, Marie Wolf and I got to see several dozen major eruptions. We missed much of the activity of the first day.

Mary Ann took these photos, and as you can see, it was cold, damp and gray that week, which made seeing the eruptions difficult at times, but it didn't snow or rain. For more details on the activity, see my article in one of the early GOSA Transactions. Think of this as a supplement to that article.

Runoff from Link Geyser eruption in Oct 1983. Photos by M.A.Moss.

Here's what we saw of one of the first eruptions we witnessed. A lot of steam coming from opaque water. The ruts produced by the runoff channel didn't get much deeper or wider over the next few days, which supports our conclusion that the first few eruptions that no one saw were even more voluminous and powerful than what we saw.

Link Geyser eruption, October 1983. Photo by M.A.Moss.

Here's one of the better photos, showing some of the details of the jets. I would estimate the height here at around 15 meters. We think we saw higher, more angled jets at times.

Link Geyser runoff, Oct. 1983. Photos by M.A.Moss.

A couple more views of the discharge from an eruption.


Next are a series of close-up views of the drained vents of the Chained Lakes.

Clasp Geyser vent, Oct. 1983. Photo by M.A.Moss.
North Chain Lake Geyser vent, Oct. 1983. Photo by M.A.Moss.
Vent between North and Middle Chain Lake Geysers, Oct. 1983. Photo by M.A.Moss.
Middle Chain Lake Geyser vent, Oct. 1983. Photo by M.A.Moss.
Bottomless Pit vent, Oct, 1983. Photo by M.A.Moss.
Link Geyser vent, Oct. 1983. Photo by M.A.Moss
Link Geyser vent, Oct. 1983. Photo by M.A.Moss

Eruption of Link Geyser, Oct. 1983. Photo by M.A.Moss.

Firehole River just after eruption of Link Geyser, Oct. 1983. Photo by M.A.Moss.
Aftermath of eruption of Link Geyser, Oct. 1983. Photo by M.A.Moss.

Note the debris washed onto the bike trail. We never saw an eruption put out enough water to reach that far, which again supports our assumption that the first eruptions were even larger.

And that's J.Randolph Railey watching the eruption.


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Grand's North Triplet Sputs


It appears that the locations and designations of the various sputs that have appeared in and around the old site of North Triplet are in need of further documentation. In going through some old files, I came across photos that Lynn Stephens took of that area in October 1989. While a lot of things there have changed since then, this does give a good record of what was happening there, and how it relates to current activity.

Sketch map of Grand's Sputs area. From 1989.

The map comes from my original GOSA Transactions article on the area, and is still a good guide. The only major difference is the disappearance of East Triplet, and the associated Sput-Cs near it.


Sputs overview, Oct 1989. Photo by L.Stephens.

In the center of this photo, with a downed branch beside it, is Sputnik, or Sput-B. To the left, the plume of steam, is Delta, or Sput-D. In the foreground are several frying pans constituting Sput-E, which are no longer active, but the area is still devoid of vegetation.


Sputs-F, Sputnik and East Triplet. Photo by L.Stephens.

On the left edge of the photo the rim of East Triplet's vent can be made out. Above and to the right, beside the downed log is Sputnik. The large brown area of dead grass is Sput-F. Eventually, three areas of activity became more pronounced and were given sub-designations.

Sput-F. Photo by L.Stephens.
Sput-F3. Photo by L.Stephens.
Sput-F1 and Sput-F2. Photo by L.Stephens.

Sput-B1. Photo by L.Stephens.
Sputnik (Sput-B), 1989 Sep 17. Photo by L.Stephens.

Sputnik also developed some satellite vents, one on each side. Over the years the craters have been filled and cleared out, so which is which is probably not possible to determine any more.


Sput-E1 and Sput-B2. Photo by L.Stephens.

In the foreground is the wet frying pan at the north end of Sput-E. Behind it, in the middle of the photo is Sput-B2, while Sputnik itself is near the top of the photo.

Note that at this time, Sput-D was a small hole which steamed heavily. Over the years it enlarged itself.


Grand Sputs in 2020. Photo by H.Koenig

The photo I took last year isn't from up close, but one can still see the are of Sput-F is still active, and the grass there hasn't recovered. Finally, here is a short video showing the area with everything that was active in June 2020.

Grand Sputs, 2020 Jun 25. Video by H.Koenig

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2021 Activity of East Sentinel Geyser


Video by H.Koenig

Some typical behavior, and some unusual behavior of East Sentinel during August and September. Chapter markers for—

  • Aug 02
  • Aug 09
  • Aug 16
  • Aug 21
  • Aug 22
  • Aug 23
  • Aug 28 13:28 Post eruption
  • Aug 30 14:30 South rim activity
  • Aug 31 06:53 Post eruption, empty
  • Aug 31 15:20
  • Sep 04 12:44 Post eruption
  • Sep 04 12:51
  • Sep 04 13:03
  • Sep 04 13:17
  • Sep 04 13:31
  • Sep 04 17:43 Minor eruption
  • Sep 04 18:37 Minor eruption
  • Sep 09 Post activity overflow cycle

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Giant Geyser Eruption of 1986 August 20


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.

View from Old Faithful Lodge

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.

Note wet boardwalk.

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...