- Current Update, last updated Oct 1, 2014 12:28 :
During September 2014, the University of Utah Seismograph Stations reports 71 earthquakes were located in the Yellowstone National Park (YNP) region. The largest event was a small earthquake of magnitude 3.2 on September 24, at 3:41 AM MDT, located about 9 miles south of Mammoth, YNP. There were no earthquake swarm sequences during the month of September.
Yellowstone earthquake activity in September is at low background levels.
Deformation in north-central Yellowstone continues, although the subsidence rate at the NRWY GPS station has slowed considerably. The total subsidence now comes close to matching the amount of uplift that had occurred previous to April 2014.
Caldera GPS stations continue to record the pattern of uplift that has persisted since the beginning of 2014. An example can be found at: http://www.unavco.org/instrumentation/networks/status/pbo/data/HVWY (click on Static Plots / Time Series)
- Volcanic History Overview: The Yellowstone Plateau volcanic field developed through three volcanic cycles spanning two million years that included some of the world's largest known eruptions. Eruption of the >2450 cu km Huckleberry Ridge Tuff about 2.1 million years ago created the more than 75-km-long Island Park caldera. The second cycle concluded with the eruption of the Mesa Falls Tuff around 1.3 million years ago, forming the 16-km-wide Henrys Fork caldera at the western end of the first caldera. Activity subsequently shifted to the present Yellowstone Plateau and culminated 640,000 years ago with the eruption of the >1000 cu km Lava Creek Tuff and the formation of the present 45 x 85 km caldera. Resurgent doming subsequently occurred at both the NE and SW sides of the caldera and voluminous (1000 cu km) intracaldera rhyolitic lava flows were erupted between 150,000 and 70,000 years ago. No magmatic eruptions have occurred since the late Pleistocene, but large phreatic eruptions took place near Yellowstone Lake during the Holocene. Yellowstone is presently the site of one of the world's largest hydrothermal systems including Earth's largest concentration of geysers.
- Location: Western US, WY
Elevation: 2805 m
- Hazard Assessments: Christiansen, R. L., Lowenstern, J. B., Smith, R. B., Heasler, H, Morgan, L. A., Nathenson, M., Mastin, L. G., Muffler, L. J. P., and Robinson, J. E., 2007, Preliminary Assessment of Volcanic and Hydrothermal Hazards in Yellowstone National Park and Vicinity, U.S. Geological Survey Open-File Report 2007-1071.
- Link to monitoring data:
Recent earthquake activity in Yellowstone National Park (map and catalog with links)
GPS Measured Horizontal Ground Motions
Provisional real-time stream-flow data
See the Yellowstone Volcano Observatory Monitoring Page for more.
Volcanic Alert Level: NORMAL Aviation Color Code: GREEN