Is it true that there's oil in Yellowstone? The surprising answer is yes, not much of it, but it's there. To learn more about that, we're standing at the Calcite Springs Overlook, looking down on the Yellowstone River. Across the canyon, we see the geologic story of Yellowstone laid out like a book. The very, very top is glacial debris from the last time we had an ice age here. When the ice melted about 14,000 years ago, it dropped all of that debris, including some of the boulders you can see at the very top of that column. Just below that is a section of lava flow. It's about 1.3 million years old. And as it slowly cooled, it formed those vertical columns that you can see on the other side of the canyon. Beneath that are sand and gravel deposits from a river system. And then below that, all the way to the bottom, are volcanic deposits from the Absaroka volcanic arc. That was a volcanic arc that looked a bit like the Cascades might today, and they shed mud flows and debris, which is preserved today at the bottom of the canyon. And at the very bottom of the canyon is the Calcite Springs thermal area. There we see not only modern hydrothermal activity, but some of those little black areas there are oil seeps. The oil formed in ancient sediments tens of millions of years old that were deposited when this was a shallow inland sea. And the Yellowstone magmatic system helped to heat some of that and push it up towards the surface. It followed some of the cracks up to the surface in these thermal areas where we can see it today. There's not much of it, but it is definitely there. Alright, now that you know the story of Calcite Springs, let's talk about earthquake, ground deformation, and geyser activity that occurred over the course of the past month. August was a pretty quiet month in terms of earthquake activity in the Yellowstone region. The University of Utah Seismograph Stations located only about 40 events. The largest was a magnitude two that occurred on August 11th over on the east side of the park. Otherwise, earthquake activity was scattered throughout the region, so pretty low activity for the month of August. Turning now to ground deformation, this is vertical deformation at the Lake GPS station over on the east side of the caldera. Each one of these blue dots is one day of data. The entire plot spans two years. Downward trends indicate subsidence and upward trends indicate uplift, and we've seen this overall subsidence trend since 2015 interrupted during the summer months by a period of a small amount of uplift, and that's caused by seasonal changes in snow melt and groundwater conditions. And you can see here that that seasonal uplift started in late June of this past year and continues through August. And finally turning to the largest geyser in the world, Steamboat Geyser. We started the month of August with no real activity there. These are just diurnal variations measured by the temperature probe that's in the geyser's outlet channel. And then starting on about August 3rd, we started to see minor activity. You can see the temperature variations, the daily temperature variations go away, and it's just a lot of random activity. This is minor eruptive activity. That suggests we're moving towards a major eruption of Steamboat possibly in the next few days to weeks. So hopefully Steamboat is gonna put on a show in September. Well, that does it for the September 2024 update of the Yellowstone Volcano Observatory. If you enjoyed this, please hit like and subscribe down below. And if you have any questions whatsoever, either leave us a comment or drop us a line. Our email is yvowebteam, all one word, @usgs.gov. Stay safe, stay healthy, and we'll see you next month. Bye-bye. Jethro, what does that sign say? It says Beverly Hills. You hear that granny, we found it. They call them hills? Why, we got moles that can push up higher ridges than that. (upbeat music)