| Note ID | Start Time (US/Mountain) | End Time (US/Mountain) | Entrant | Note |
| 37891 |
31 Oct 2024 @ 1643 |
--- |
SantaFe108 |
~1.5ft below the alcove roof with yellowish-brown murky water. Right-side boil. |
| 37838 |
29 Oct 2024 @ 1655 |
--- |
MAB |
steamy but basically same water level as before - Yellow Mud area behind a little less active than 27th |
| 37803 |
27 Oct 2024 @ 1346 |
--- |
MAB |
wow low! steady boil NE portion - water below bottom of cove in S wall |
| 37729 |
24 Oct 2024 @ 1556 |
--- |
SantaFe108 |
Low, 1.5ft below alcove roof. Right-side boil in murky yellowish-brown water. Right vent dry. Spring behind and to the left boiling and putting out copious overflow in all directions. |
| 37480 |
10 Oct 2024 @ 1020 |
--- |
SantaFe108 |
Also very high, ~2" above roof of alcove. Left vent connected, clear and blue. |
| 37375 |
03 Oct 2024 @ 1525 |
--- |
SantaFe108 |
Full of clear, aqua water. Right vent connected to main pool and alcove underwater! Pool level about 5in below rim on alcove side. |
| 37221 |
28 Sep 2024 @ 1705 |
--- |
cb |
pool is also very high. water is turquoise blue clear & calm (steamy) |
| 36584 |
27 Aug 2024 @ 1856 |
--- |
cb |
pool is high. water covering and above the alcove on its west end. clear and greenish in color |
| 35424 |
21 Jun 2024 @ 1535 |
--- |
nails |
Light blue with some bubbling in back right side. |
| 35091 |
10 Jun 2024 @ 1254 |
--- |
SantaFe108 |
Slightly cloudy, aquamarine water. Water level is about 6 inches from the top of the left alcove. |
| 35002 |
08 Jun 2024 @ 1134 |
--- |
cb |
Clear, calm & beautiful blue color. pool level is half way into the alcove to the west |
| 34699 |
26 May 2024 @ 0804 |
--- |
ypcaribou |
Abdolutely clear turquoise blue.Full. |
| 34259 |
19 Apr 2024 @ 1533 |
--- |
MAB |
Beautiful clear blue!!! - quite full up into the little cove but couldn't see water level in there due to light and steam - not full enough to top the NE ledge by that nearby vent |
| 29030 |
22 Oct 2023 @ 0854 |
--- |
SantaFe108 |
~1½ feet below the alcove roof, bubbling in many places with cloudy green water. |
| 28971 |
21 Oct 2023 @ 1529 |
--- |
JR |
2 feet below rim. A murky green, a bit opaque. Slight bubbling. |
| 28926 |
20 Oct 2023 @ 1608 |
--- |
MAB |
greenish fairly clear - dropped lower to bottom quarter of the wall cove - LOTS bubbles from several points - more on right side - YELLOW MUD SPRING behind it had a solid large area of upwelling - usually fairly cool back there! |
| 28765 |
14 Oct 2023 @ 1317 |
--- |
SantaFe108 |
Water level into the alcove, clear and blue. |
| 28788 |
14 Oct 2023 @ 1220 |
--- |
MAB |
clear |
| 28634 |
05 Oct 2023 @ 1200 |
--- |
cb |
turquoise blue, calm & 1' below high water mark! |
| 28505 |
26 Sep 2023 @ 1717 |
--- |
MAB |
Clear blue-green and quiet - water level more than halfway up the cove on ~SW side |
| 27294 |
28 Jul 2023 @ 2038 |
--- |
SantaFe108 |
Water level half-way up the cove and spectacularly clear and blue. |
| 26827 |
04 Jul 2023 @ 0859 |
--- |
MAB |
clear pretty- water halfway up the cove |
| 25964 |
02 Jun 2023 @ 1032 |
--- |
Tara |
clear and beautiful pale blue, water level just above overhang on right side |
| 25861 |
28 May 2023 @ 1950 |
--- |
SantaFe108 |
Brilliant blue clear water. Water level just up to the cove on the left of the pool. Far right vent is dry. |
| 25661 |
21 May 2023 @ 1435 |
--- |
SantaFe108 |
Spectacular blue color. Water level up to right inside the little cove on the left. Far right vent is dry. |
| 24402 |
15 Oct 2022 @ 0953 |
--- |
MAB |
half full and into the cove on wall - clear blue green and calm |
| 24250 |
05 Oct 2022 @ 1229 |
--- |
cb |
Not much change, pool is about 3" lower than last observation. color is deep blue and pool is calm & clear |
| 23961 |
20 Sep 2022 @ 1635 |
--- |
ypcaribou |
Clear, deep blue. Water tops out about 1 ft down from rim. This one wins the clearest bluest award for today's walkabout. |
| 23499 |
31 Aug 2022 @ 1120 |
--- |
cb |
Steaming, calm, blue, (visitor just said Listerine blue) high. water is halfway up into the alcove toward NBK-8. |
| 22983 |
02 Aug 2022 @ 1029 |
--- |
cb |
Only change is the clarity of the pool. A bit more cloudy. pool level is just at the bottom of the cave on the west end. |
| 22919 |
27 Jul 2022 @ 1614 |
--- |
MAB |
pretty blue color filled halfway up the inner cave like area - calm - little vent nearby the right edge still high and dry |
| 22318 |
04 Jul 2022 @ 1439 |
--- |
cb |
pool down 8" at least, calm and beautiful blue color |
| 22117 |
25 Jun 2022 @ 1133 |
--- |
cb |
calm, clear, deep blue color and same pool level as last observation. water is up to & covering the small cave on the west edge |
| 21607 |
31 May 2022 @ 1453 |
--- |
cb |
pool level also very high, up to & covering the alcove on the west edge of the pool. water is clear & calm. no boil. |
| 21329 |
16 May 2022 @ 1110 |
--- |
Tara |
Clear and blue, water level just at the overhang on the left side. |
| 21012 |
18 Apr 2022 @ 1716 |
--- |
MAB |
Clear blue in color about half full - nearly to the top of the SW cove vent but not full enough to connect with the NE sulphury vent |
| 20295 |
04 Nov 2021 @ 1225 |
--- |
MAB |
higher water than this summer - over that inner ledge but still only about half full |
| 20054 |
19 Oct 2021 @ 1404 |
--- |
cb |
pool is higher, covering the rock point. has a few small bubblers in the pool. |
| 19810 |
30 Sep 2021 @ 1235 |
--- |
cb |
Same water level. pool is emerald green in color, calm, mostly clear & steamy. #7 pool is cloudy greenish color, calm & #8 is yellowy in color with a 4" blooping boil on the edge toward Yellow Funnel spring & it is not in overflow. |
| 19607 |
16 Sep 2021 @ 1032 |
--- |
cb |
water level is ~2.5' below the rim. Water is amazingly clear, green in color and steaming |
| 19625 |
16 Sep 2021 @ 0929 |
--- |
MAB |
low - water still clear |
| 19372 |
08 Sep 2021 @ 1135 |
--- |
Tara |
Clear greenish water, calm, down 3' |
| 18506 |
18 Jul 2021 @ 1048 |
--- |
cb |
Pool has dropped another ~3". Opalescent blue with a slight yellowy tinge on the edges |
| 18327 |
09 Jul 2021 @ 1330 |
--- |
MAB |
still low low low - opalescent blue - down 3 ft - that little vent on the shelf on the NE side that would dribble sulphur into Mud is still high and dry |
| 18184 |
29 Jun 2021 @ 1323 |
--- |
cb |
no change in water level. no boil or bubbles, color is a milky opalescent blue |
| 17724 |
12 Jun 2021 @ 1620 |
--- |
MAB |
4 feet below high water marks- incredibly low |
| 17574 |
08 Jun 2021 @ 1112 |
--- |
cb |
water level up 6" since last observation. color is opalescent turquoise blue and calm |
| 17277 |
30 May 2021 @ 1554 |
--- |
cb |
very low, 1.5 - 2' below smooth water mark on the north rim. The rock outcropping that sticks out into the pool is barely covered with water. pool is a opalescent milky turquoise blue in color and calm. |
| 16395 |
10 Oct 2020 @ 1020 |
--- |
cb |
same as as last observation. Water is calm and turquoise blue. |
| 16342 |
06 Oct 2020 @ 1224 |
--- |
cb |
water level is down 2' from the rim of the pool. It is steamy, ( 65°today) clear and blue in color. Pool appears lower by a few inches than I observed last time. |
| 16271 |
26 Sep 2020 @ 1626 |
--- |
cb |
water level is about 2' down from the rim. This is about 4" down from my observation 3 weeks ago. Pool is calm, blue green in color and has no bubbles or boil |
| 29158 |
30 Jul 2020 @ 1200 |
--- |
research-mab |
7/30/2020 - no time noted-- Big Pool S of Mystic {Mud Spring? ← written in} – dramatic color change! Much darker green not turquoise |
| 13253 |
14 Aug 2019 @ 1615 |
--- |
cb |
up a tad bit but still a good 2'+ down from the rim. (not overflow) Covering the rock peninsula on the south edge inside the pool. it is a milky blue color and calm. |
| 12996 |
03 Aug 2019 @ 0839 |
--- |
cb |
down 8". greenish blue in color |
| 12970 |
02 Aug 2019 @ 0938 |
--- |
MAB |
pretty green- water level still low |
| 11023 |
20 Apr 2019 @ 1035 |
--- |
MAB |
Low, very low water, but a pretty greenish color. Clear. |
| 9967 |
31 Aug 2018 @ 1034 |
--- |
MAB |
Nearly full, well over the shelf on the east. Not quite up to the sulfur-y vents yet, but much more water. Clear, beautiful blue water |
| 9622 |
10 Aug 2018 @ 1339 |
--- |
MAB |
LOW water, clear beautiful blue. |
| 29620 |
02 Aug 2017 @ 1200 |
--- |
research-mab |
8/02/2017 - no time noted - Mud Spring, south of Mystic Spring has changed from a blue color to more of a green color. |
| 29614 |
23 Jul 2017 @ 1200 |
--- |
research-mab |
7/23 - no time noted - (possibly Mud Sp? mab) - Moon= low pools? The pool just west of Mystic Spring is ~2 ft down than normal |
| 29592 |
25 Aug 2016 @ 1200 |
--- |
research-mab |
8/25/2016 - no time noted - Mud Spring has changed color to a clear sapphire blue, very pretty |
| 2789 |
24 Apr 2016 @ 1500 |
--- |
sfavor |
Mud Spring looked like it had a large eruption with spray approximately 30' uphill. |
| 29777 |
30 Aug 2007 @ 1200 |
--- |
research-mab |
8/30/2007 .- no time noted - • The usually quite clear and murky pools between Echinus and Puff’n Stuff were turbulent – small areas of water gushing in the pools about 6-12 inches. |
| 30130 |
18 Aug 1995 @ 1200 |
--- |
research-mab |
8/18/95 - no time noted - Emerald Pool is no longer having the heavy boils seen since the beginning of disturbance on the 29th.Water levels remain lower than “usual” & heavy boils continue in Crater, Mystic & Mud Springs. |
| 30299 |
07 Sep 1993 @ 1200 |
--- |
research-mab |
Sept 7 1993 - no time noted - Also Mud Spring & Mystic spring low. [NOTE during these years there was confusion about Mystic, Mud and NBK8 so very few single entries will be entered here - A note containing both will work - mab] |
| 31004 |
18 Jul 1984 @ 1200 |
--- |
research-mab |
7/18/1984 Thermal Observations - no time noted - Mud Spring – active 184º |
| 31096 |
21 May 1983 @ 1200 |
--- |
research-mab |
May 21 1983 – no time noted ~afternoon - Mud Spring – Translucent grey, heavy boiling from the cente |
| 31304 |
08 Jul 1982 @ 1200 |
--- |
research-mab |
7/8/1982 - “About 1200” - Mud Spring – muddy, splashing boiling, cloudy green-grey |
| 31288 |
07 Jul 1982 @ 1200 |
--- |
research-mab |
7/7/1982 - no time noted - Mud pool & others nearby = constant bubbling |
| 31262 |
10 Jun 1982 @ 1200 |
--- |
research-mab |
6/10-82- no time noted - Mud Spring 171°F not overflowing, muddy grey/tan |
| 31232 |
20 Feb 1982 @ 1200 |
--- |
research-mab |
February 20 1982 - no time noted - Mud Spring 188° green-brown medium turbid H2O that is much clearer than normal. |
| 31177 |
14 Jan 1982 @ 1200 |
--- |
research-mab |
January 14th 1982 - no time noted - Mud Spring 152° bright green slightly turbid |
| 31536 |
30 Aug 1981 @ 1200 |
--- |
research-mab |
Sunday August 30 1981 - no time noted - Mud Spring gray turbid H2O bubbling to 8” 179° |
| 31452 |
02 Aug 1981 @ 1200 |
--- |
research-mab |
Sunday August 2 1981 The Basin Wide Disturbance has occurred! - no time noted - Mud Spring Light green turbid opalescent water that is constantly bubbling 158° |
| 31416 |
06 Jun 1981 @ 1200 |
--- |
research-mab |
Saturday June 6 1981 - no time noted - Mud Spring – gray-beige, calm, no overflow 171 F |
| 31739 |
07 Sep 1980 @ 1200 |
--- |
research-mab |
Sunday Sept 7 1980 - no time noted - Mud Spring – periodic boiling to 1 foot, turbid blue-green – evidence of slight overflow 179°F |
| 31702 |
16 Aug 1980 @ 1200 |
--- |
research-mab |
Sat Aug 16 - no time noted - Mud Spring- Cloudy green and gently bubbling. No overflow. 170°F |
| 31638 |
09 Jun 1980 @ 1200 |
--- |
research-mab |
June 9 1980 - no times - observations made over the week and entered on 9th - Mud Spring- opaque green and bubbling 169ºF |
| 32024 |
11 Oct 1979 @ 1200 |
--- |
research-mab |
October 11 1979 – no time noted - Back Basin...changes since disturbance. Mud Spring is very turbid and is a grey-green instead of aquamarine. |
| 32007 |
28 Sep 1979 @ 1200 |
--- |
research-mab |
September 28 1979 - no time noted - Mud Spring – 177ºF, pale, opaque aquamarine, very gentle boiling |
| 31897 |
17 Aug 1979 @ 1200 |
--- |
research-mab |
Aug 17 1979 - no time noted - Mud Spring - 169ºF – aqua-marine color |
| 31828 |
03 Jun 1979 @ 1200 |
--- |
research-mab |
June 3 1979 - no time noted - Mud Spring is still clearing as is Phillips Cauldron. |
| 31825 |
27 May 1979 @ 1200 |
--- |
research-mab |
May 27 1979 - no time noted - Mud Spring is clearer today and still beautifully blue |
| 32049 |
25 Mar 1978 @ 1200 |
--- |
research-mab |
March 25 1978 - no time noted - Mystic & Mud Springs – full of water, clear blue & beautiful! |
| 32304 |
19 Aug 1977 @ 1200 |
--- |
research-mab |
08/19/1977 - no time noted - changes- Mud Spring is opaque and still retains its color. Decker Geyser is boiling in many spots. Emerald Spring has extended its area of boiling along the edge parallel to the trail and is murky. |
| 32290 |
18 Jul 1977 @ 1200 |
--- |
research-mab |
07/18/1977 - no time noted - Yellow Funnel and Mud Springs are clearer than I’ve seen for a few days.
. |
| 32278 |
08 Jul 1977 @ 1200 |
--- |
research-mab |
07/08/1977 - no time noted - Yellow funnel and Mud Spring were murkier than previously this summer. |
| 32481 |
15 Aug 1976 @ 1200 |
--- |
research-mab |
08/15/1976 - no time noted - Root Pool and Green Dragon Spg & Muddy Spg. Both bubbling quite vigorously and quite turbid. A call to Old Faithful visitor center verified the hypothesis that the park had a slight tremor which caused the aforementioned change in B. Basin Spg activity. |
| 32457 |
31 Jul 1976 @ 1200 |
--- |
research-mab |
07/31/1976 - no time noted - Mud Spring – appears to be clearing. |
| 32451 |
27 Jul 1976 @ 1200 |
--- |
research-mab |
07/27/1976 - no time noted - Mud Spring water level down about 4 feet |
| 32444 |
24 Jul 1976 @ 1200 |
--- |
research-mab |
07/24/1976 - no time noted - Mud Spring: is muddy!! |
| 32842 |
24 Sep 1973 @ 1200 |
--- |
research-mab |
09/24/1973 - no time noted - Back Basin - Water levels up in those springs which have been low: Yellow Funnel, Phillips Cauldron, Mud Spring (now rather clear blue-green), Mistic [sic] -levels seen up ~6” - - which is ~ down from the normal (high water mark) level except for Phillips Caldron which is about 10” below high water mark. |
| 32806 |
11 Sep 1973 @ 0900 |
--- |
research-mab |
09/11/1973 Back Basin 900 am - Water levels seem somewhat lower in features showing that state – mainly: Mystic, Dishwater S, Phillips Cauldron, Mud S., Yellow Funnel; drainage pools near Dishwater have water only in the depressions – the flatter areas have the water. |
| 32801 |
08 Sep 1973 @ 1200 |
--- |
research-mab |
09/08/1973 - Back Basin 8:30 am -Water levels low: Mystic, Mud, Phillips, Yellow Funnel |
| 32787 |
03 Sep 1973 @ 0900 |
--- |
research-mab |
09/03/1973 - no specific times - Back Basin 900am - Muddy Spring (low) Mystic Spring (low) |
| 32777 |
02 Sep 1973 @ 1115 |
--- |
research-mab |
09/02/1973 - no specific time noted - Back Basin at 1115am - Water levels low in Mystic (fairly clear), Mud Spring (fairly clear- down ~ 1’), Yellow Funnel Spring (muddy), pool area (w/mud) to NE of Dishwater Spring, Green Dragon (still a couple of inches down & churning muddy), Pearl Spring w/little runoff; Bathtub; |
| 32763 |
29 Aug 1973 @ 1200 |
--- |
research-mab |
08/29/1973 - no time noted - Back Basin @ 8:am Green Dragon is still brown; water level down in Mystic Springs (sev inches), and down in Spring to S.W. (maybe ½’).{Mud Spring? mab} |
| 20376 |
09 Sep 1972 @ 1200 |
--- |
research-mab |
09/09/1972
Mud Spring & “Yellow Green Pool” to the east have started to refill. [generic day time] |
| 32921 |
07 Sep 1972 @ 1200 |
--- |
research-mab |
09/07/1972 - no time noted - Although the water level seems to be returning to “normal” in most features in the Porcelain Basin, many of the features in the Back Basin (ie Mud, Mystic, Yellow Funnel and Dishwater springs, corporal geyser & Dog Leg) are still low, turbulent and muddy. |
| 32920 |
02 Sep 1972 @ 1200 |
--- |
research-mab |
09/02/1972 - no time noted - Mud Spring – water now down 13 inches turbid bubbling brn – up to 3 feet. |