- Current Update, last updated Aug 1, 2014 10:05 :
During July 2014, the University of Utah Seismograph Stations, responsible for the operation and analysis of the Yellowstone Seismic Network, reports 99 earthquakes were located in the Yellowstone National Park region. The largest event was a magnitude 2.5 on July 6, at 09:54 AM MDT, located about 18 km (11 miles) north northeast of Old Faithful, Yellowstone National Park.
Over half of July seismicity occurred July 6-7th and is a result of the ongoing north-south trending series of earthquakes, over 11 km (7 miles) in length, which began in September, 2013. Including the largest July earthquake of magnitude 2.5.
Earthquake sequences like these are common and account for roughly 50% of the total seismicity in the Yellowstone region.
Yellowstone earthquake activity in July remains at normal background levels.
Deformation in north-central Yellowstone continues, with the subsidence rate holding steady for the last month at around 10 cm/yr. Since the subsidence began in early April 2014, the NRWY GPS station has dropped about 5 cm.
The eastern caldera GPS station WLWY, which we often refer to in these updates, has been offline since June 30, 2014. Other caldera GPS stations continue to record the pattern uplift that has persisted since early 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