- Current Update, last updated Sep 2, 2014 11:04 :
During August 2014, the University of Utah Seismograph Stations, responsible for the operation and analysis of the Yellowstone Seismic Network, reports 207 earthquakes were located in the Yellowstone National Park (YNP) region. The largest event was a small earthquake of magnitude 2.2 on August 6, at 5:55 AM MDT, located about 15 miles southwest of Mammoth, YNP. The August earthquake sequences are described below.
1) The largest series of earthquakes (74 ranging in magnitude from -0.9 to 2.0) occurred August 18 - 21, just outside of YNP, about 6 miles north of West Yellowstone, MT.
2) A small series of 34 earthquakes (magnitudes -0.1 - 1.5) occurred on August 15 - 22, located about 6 miles south southwest of Lake, YNP.
3) On August 16 a small series of 11 earthquakes (magnitudes 0.6 - 2.1) occurred about 1.6 miles south southwest of West Thumb, YNP.
Earthquake sequences like these are common and account for roughly 50% of the total seismicity in the Yellowstone region.
Yellowstone earthquake activity in August remains at normal background levels.
Deformation in north-central Yellowstone continues, although the subsidence rate at the NRWY GPS station has slowed considerably over the last month to just less than 5 cm/yr.
The eastern caldera GPS station WLWY remains offline. Other caldera GPS stations continue to record the pattern of uplift that has persisted since the beginning of 2014.
- 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