Last Known Eruption
6y 78d 3h 25m ago

Latest Eruptions

Eruption DurationInterval
07 Jul 2014 @ 000012y 282d 0m
01 Oct 2001 @ 0000 A27y 54d 0m
15 Aug 1974 @ 000044d 0m
02 Jul 1974 @ 000014d 0m
18 Jun 1974 @ 000010d 16h 0m
07 Jun 1974 @ 0800 A2y 246d 8h 0m
05 Oct 1971 @ 0000

Interval Statistics

Interval Count6
Min10d 16h 0m
Max27y 54d 0m
Mean7y 47d 16h 0m
Median1y 145d 4h 0m

Latest Notes

Note IDStart Time (US/Mountain)End Time (US/Mountain)EntrantNote
12014 28 Jun 2019 @ 0745 28 Jun 2019 @ 1045 ypcaribou Water in springs below and to the left of Arch Steam Vent about 1-2 feet low.
11028 20 Apr 2019 @ 1031 --- MAB Noisy forced steam
9661 10 Aug 2018 @ 1331 --- MAB Pools below and west are 3 different colors - might suggest different water sources. 1st (closest to Arch) is grayish white, 2nd green, 3rd is taupe.
3998 22 Apr 2017 @ 2020 --- Micah Kipple Heavy wash and debris downslope. Sinter blocks and stones lodged on uphill side of trees and logs. Looks wet but that could be snow melt.
1101 07 Jul 2014 @ 0000 07 Jul 2014 @ 2359 MAB Norris log - Arch Steam Vent showing evidence of eruption- runoff channel and fresh debris in the path
4356 02 Oct 2001 @ 0800 02 Oct 2001 @ 1800 research-mab 10/2/2001 A visitor reported a lot of mud around Arch Steam Vent today. I left the desk briefly to check it out. John Tebby & I walked down and found trees covered in mud, huge mud flows around the boardwalk and a big sink hole in the inside of the boardwalk (NW of the vent). There was a light spatter of mud on the boardwalks as far away as 25 feet. Last recorded eruption {obscured in my captures of the log -will probably find it as I work back in time MAB}
4749 30 Sep 2001 @ 1800 --- research-mab 09/30/2001 ARCH STEAM VENT: Erupted w/ sprays of mud & mudflows & opened up a sink hole. Time unknown.
10891 25 Apr 1994 @ 1200 --- research-mab 4/25/1994 {generic day time} A little water was seen from Arch Steam Vent
5719 15 Aug 1974 @ 1800 --- research-mab 08/15/1974 Arch Steam Vent runoff damp – sign & log retrieved from trees nearby.
5716 02 Jul 1974 @ 1800 --- research-mab 07/02/1974 Arch Steam Vent (Geyser) – has erupted sometime in past 2 days. Marker washed out.
5709 18 Jun 1974 @ 1120 --- research-mab 06/18/1974 1120 Marker at Arch Steam Vent washed out, replaced.
5706 07 Jun 1974 @ 1800 --- research-mab 06/07/1974 1655 Visited Arch Steam Vent- definite evidence of eruption w/ hot water in runoff channel. Placed pine-needle marker in runoff channel. {during day - no time noted}
10892 14 May 1972 @ 1000 --- research-mab 5/14/1972 {generic time} Arch Steam Vent {1st observations of the season noting destruction from early Oct 1971 eruption~ 1972 Annual report states it was September {disturbance} activity~~~ included here as some readers of the log may assume a May 1972 eruption.} 5-14-72 Lognote: had one heck of an eruption The erosion in this area is impressive – a new hole opened up to the north and is filled with green water. The trail no longer branches back to the feature
10865 05 Oct 1971 @ 0000 --- research-mab {Seen and photographed Oct 6. eruption presumed night of Oct 5} There was no warning at all to the vent change other than a temperature rise of 1°F on September 12th. When it erupted, the vent was enlarged, its shape changed markedly, muddy water coated the trees clear to the top to a distance of over 80 feet from the vent, the log sign identifying Arch Steam Vent was rolled 30 feet down the slope; in addition mud, pine needles, small logs, and the other debris were washed over the boardwalk below the vent, a gully about a foot in depth was eroded into the hillside, and a small pool to the west-northwest served as a catchment basin for part of the runoff but its level dropped around 2 feet from normal.
10864 02 Jun 1968 @ 0000 --- research-mab Arch Steam Vent June 2 1968 The vent blew up some time this spring. The arch is no longer intact and the trees to the north are dead and covered with gray clay. Clay has also run down the hill on to the trail.
No attachments for this geyser.
Baseline does not exist.

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