Sawmill Group: Where we last left them in 2017
One group of geysers and hot springs I’m curious about any changes seen is the Sawmill Group, over near Grand Geyser a little way beyond Old Faithful. The group that “normally” has either Sawmill Geyser in charge of the eruptions or Penta and Churn Geysers in charge of the group. I say “normally” because thermal features often surprise us with different behavior.
The last known eruption of Sawmill Geyser was January 29, 2017 – so over a year ago. Last May I posted about them and the changes seen. Pauses like this have been reported in the past, so I’m wondering if this is just another behavior in this group not often seen. Geyser gazers visiting Yellowstone this last winter reported no big changes, but I wanted to pull together the photos I took toward the end of the summer season to remind me where they were when last seen.
OVAL SPRING
The most interesting change in this group was Oval Spring. Earlier in the summer, the crater of this smaller geyser was lined with yellow microbes. By October 15, 2017, the yellow was much less pronounced and there were steady fast bubbles rising from one section where I don’t recall seeing any bubbles before.
SAWMILL GEYSER, PENTA GEYSER and TARDY GEYSER
The rest of the group looked fairly similar to what I saw earlier in the season. Sawmill Geyser, Penta Geyser and possibly Tardy Geyser and apparently Oval Spring appeared to me to rise and fall a few inches that fully matched the water level in Spasmodic Geyser and cycled with it. The snow on the ground made the thermal energy from Sawmill Geyser and “Uncertain Geyser” very clear. Penta Geyser still had a small section with microbes in it. Tardy Geyser was either completely calm while I was there, or made a half-hearted splash every couple of minutes. This was seen throughout the summer, so there were active periods and quiet periods of this half-hearted attempt.
TWILIGHT SPRING
Twilight Spring was a bit cooler with darker microbes showing instead of the lovely bright orange ones seen this summer. However, I personally attribute that to cooler temperatures outside and this type of change is typical as winter moves in and takes hold. What I found interesting in this photo is that it seems Twilight Spring might have had periods of heavier overflow. I don’t recall seeing that in the summer – instead I saw a very small change in water level, but it also coincided with Spasmodic Geyser’s cycle.
“NIFTY GEYSER”
Throughout the summer, “Nifty Geyser” sent a fairly strong spray up to maybe a foot (more or less). During this visit in October, “Nifty” was decidedly less enthusiastic.
DOWN BASIN
Apparently, I missed a photo of Churn Geyser – being distracted by an eruption of Grand Geyser. After Grand, I walked a bit farther down basin and took more photos – the more interesting ones that might show marked changes this spring were Topsoil Spring and Economic Geyser.
Opening Weekend in Yellowstone
I’m not sure at this point if I’ll make it in to the geyser basins to check on things, or if my first visit this summer season will need to wait until the East Gate opens on May 4. I should know more soon. If I go, you can follow me on Instagram. If not, I look forward to all the reports on Geyser Times.