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Height Baselines

With the interest last year in measuring geyser eruption heights, I thought it might be useful to repost this. I managed to extract the text out of a file with an obsolete format. The year on the file is 1986 and I think it was something that ran in one of the earliest issues of The Sput that T.Scott Bryan put out.

Despite the number of years since, and the number of changes to the boardwalks, more than a few of these markers can still be found if one knows where to look. The washer is usually gone, but the nail or screw remains. There are also a few markers I noticed that aren't on this list, and don't seem to be associated with any obvious, nearby geyser. I think a project for next summer will be to see how many I can still find and recover.

We usually measured baselines at night. We'd let Rick Hutchinson and the Protectives (as they were known then) know we were out and about, and then spend a few hours surveying. Sam Martinez did most of the work at the vent for most features, as he'd done it before and knew the better approaches for geysers like Castle. On 1986 August 19, a bunch of us went out to Shoshone Basin for the day. That evening, we did the markers in and around Daisy and Splendid. As we finished, Sam wanted to go out and place markers in the Giant Group, too. I was tired by then, and suggested there wasn't much point, as they'd probably all be stolen before we ever got to use them. The next day, Giant erupted, the first time seen by gazers since 1978. That night, we went out and placed the markers. Since I saw the start of Giant, I got to be the one holding the tape over the vent. Twelve hours after an eruption, at a time when you know it can't possibly erupt, that is still a bit of a thrilling and scary place.

I also have a copy of a video Paul Strasser made of baselines for New Crater/Steamboat being measured in 1991. On it, they determine that the southwest corner of the lower platform is about 110ft from the South Vent.


Over the past few years, a number of height baselines have been surveyed in the geyser basins by Sam Martinez, with the assistance of several other geyser gazers. Each baseline is marked with a metal disk about 1 inch in diameter impressed with the geyser's name, basin, and its distance.

While placed primarily for measuring and studying geyser heights, they can be useful for the casual observer. Just remember that at a 45° angle the height equals the distance, and you can get a feel for how high the eruption really is. The distances were chosen so that the measured angles would be between 30° and 45° in most cases. The other primary criterion was that the markers must be accessable to everyone. All markers (except Round’s) are located on legally accessable pathways, boardwalks or roads.

Baselines of 100' or less are directly determined with a tape measure from directly over the geyser's vent. Those greater than 100' were determined with an intermediate point located halfway (when possible). When a geyser's water column is sharply angled (for example: Daisy, Vent or Riverside), the baseline is measured from the point directly below the point of greatest height for a typical eruption.

All of the markers currently placed and maintained are listed in the table, along with the distance and a short description of the location. Sometimes these markers have disappeared, probably as a strange souvenir. Please report any disappearances to Sam or myself.

GeyserDistanceNotes
Aurum50South on boardwalk
50North on boardwalk across from Beach
Beehive200Northwest on boardwalk, near Depression
200East on boardwalk, between Plume and Anemone
≈275South on boardwalk corner across river *
Castle200South on asphalt trail east of first tree
100North on boardwalk, 6th railing upright
Clepsydra100Southeast on boardwalk near Spasm
100Southeast on boardwalk near Jelly
Daisy200Southwest on asphalt, near bridge over runoff channel
100West on boardwalk, beside Splendid
100North on boardwalk †
Fan & Mortar100Large rock east of asphalt and benches
Fountain100South on boardwalk near Jet
100Southwest on boardwalk near Spasm
Giant200South on boardwalk
200North on boardwalk, behind trees
Giantess200Northwest on boardwalk, northwest of Pump
222South on boardwalk, beside Anemone
≈260Northwest on boardwalk beside Infant
Grand200South on asphalt beside trail junction near Belgian
200Northwest on boardwalk, south of unnamed gray pool
≈110West on boardwalk beside prediction sign *
Great Fountain200East on asphalt, across from prediction sign, at end of painted line
200Northeast on road between 3rd and 4th culverts
Grotto Fountain100Southwest on cement block east of walkway
Lion100Northeast on boardwalk, near North Goggle and boardwalk junction
100Southeast on boardwalk
Mastiff100West on short boardwalk over Daisy's runoff channel
Morning200Southeast on boardwalk just west of stairs
200Southwest on boardwalk east of Jelly
Oblong150On northeast bridge abutment
130Northwest on boardwalk
Penta50Southwest on boardwalk, near trail junction
50North on boardwalk, beside Oval
Pink Cone50Northeast on asphalt
50Southwest on asphalt
Plume50East on boardwalk between markers for Beehive and Giantess
50West on boardwalk over Plume runoff channel
Rocket100Southwest on asphalt, south of junction with boardwalk
100Northwest on asphalt, west of Grotto Fountain
Round Geyser100North
100West
Sawmill50Southeast on boardwalk, near Tardy
50West on boardwalk, near Churn
Spa50North on asphalt, on small trail loop
50SW on asphalt
Splendid200Southeast on asphalt, near benches south of Bonita
200South on boardwalk, near west end
200West on boardwalk, at sharp bend to south
200Northeast on boardwalk †
Vent100West on boardwalk over Grand's main runoff channel
100Northwest on boardwalk
White Dome100On boardwalk near asphalt
100South on boardwalk
110On asphalt at end of parking area

* Estimated, no marker actually placed.
† These two markers are about 20' apart.