In Yellowstone National Park, a bulge the size of 279 football fields has risen by an inch since last July. With no signs of slowing down, the bump that’s roughly 19 miles across may cause some worry that the iconic locale’s hibernating supervolcano is readying for an apocalyptic reawakening. Although impressed by the situation, the Yellowstone Volcano Observatory’s scientist-in-charge doesn’t sound particularly worried.
“I think it’s pretty stunning even if it’s not particularly unusual,” Mike Poland recently explained to Cowboy State Daily.
This particular example of uplift or deformation is occurring at the northern rim of Yellowstone Caldera in northwest Wyoming. However, it’s far from the first time researchers documented the geological occurrence. The most recent instance spanned around 16 years before wrapping up in 2020. In 1996, yet another deformation took place over four years. These events aren’t visible to the average park visitor, but they can be dramatic when viewed by highly sensitive seismological equipment and other observational tools.
“We can see things that are moving up and away from this area of uplift on radar maps and satellites we use to measure this sort of thing,” said Poland, adding that his team monitors the park with 17 GPS stations that help determine where the uplift started.
While the chance for an eruption is extremely low, the supervolcano is still likely to blame. A 2025 study from the United States Geological Survey determined that Yellowstone’s magma chamber currently contains a low amount of molten rock, but there is still enough for some activity. Poland theorizes the bulging is owed to an “accumulation and withdrawal” of magma about nine miles below the Earth’s surface. If an eruption was in the cards, the deformation would also be much shallower. Poland says that since there is a known magma chamber, it is “not surprising that there’s stuff moving around down there.”
If anything, last year was particularly calm for Yellowstone. The park annually experiences an average of 1,500 to 2,500 earthquakes, but scientists recorded only 1,119 earthquakes in 2025. So while the bump may continue to rumble for years to come, it’s just Yellowstone being its same, wondrous self.
2025 PopSci Best of What’s New
