The Yellowstone volcano thermal area has appeared in the northern part of the National park and is visible via Google Earth. There are more than 10,000 thermal features across the supervolcano park, which range from scorching geysers to hot springs. All of these thermal features are evidence of the intense magmatic processes deep beneath Yellowstone. But the features are ever-changing and as they heat up and cool down, the USGS said they can move around Yellowstone.
USGS scientist Greg Vaughan said in the latest Caldera Chronicles: “These sorts of changes are part of the normal life cycles of thermal areas in Yellowstone National Park.
“Recently, we have discovered another phenomenal example of thermal change – the emergence of a new thermal area, which has taken place over the past 20 years.”
The new area was found just to the east of Tern Lake, another prominent thermal area in the region.
Geologists observed the first inklings of the developing area in 2006, thanks to detailed satellite imagery of the park.
Satellite photos of the now recognised thermal area, taken in 1994 show an area of healthy tree growth and vegetation near Tern Lake.
However, by 2006, photos snapped for The National Agriculture Imagery Program (NAIP) revealed the first signs of a “tree kill zone” and patches of barren vegetation appearing where the soil was heating up.
The latest satellite images taken in 2017 have since shed light on the expanding area of dead trees and bright soil reminiscent of a thermal area.
You can find the thermal area on Google Earth or Google Maps by punching in the coordinates 44.6635° N, 110.279° W.
The USGS said: “The 1994 air photos, while black and white and lower spatial resolution, clearly show that this was once an area of healthy trees with no hint of a thermal area.
“Other historical imagery that have been analysed indicate that this thermal area started forming in the late 1990s or early 2000s.
“It is also notable that between 2006 and 2017 there was an increase in the size of the tree kill zone on the north side of the previously mapped Tern Lake thermal area.”
Geologists use the term thermal area to describe one or more thermal features, such as geysers or fumaroles, surrounded by shifting ground, gas emissions or heated ground.
Most of Yellowstone’s thermal features are clustered in just 120 thermal areas such as the Upper Geyer Basin, Norris Geyser Basin and Tern Lake.
Many of these areas are hidden away in the more inaccessible and wild parts of the park where tourists rarely dare to venture.
Because of this, scientists from the Yellowstone Volcano Observatory (YVO) branch of the USGS have to rely on satellite images to track the changes in Yellowstone.
The USGS said: “The recognition of the new thermal area is a great example of the importance of satellite thermal infrared imaging – especially images acquired at night – for mapping Yellowstone’s thermal areas.
“This is exactly the sort of behaviour we expect from Yellowstone’s dynamic hydrothermal activity and it highlights that changes are always taking place, sometimes in remote and generally inaccessible areas of the park.”