Recent Earthquakes in Vermont
11 mild earthquakes with epicenters in Vermont occurred between January 1, 2016 and December 7, 2018. A 2.1 magnitude earthquake occurred at 9:30 am (EST) on December 6, 2018. The epicenter was reported as 8 km WNW of White River Junction. A 2.3 magnitude earthquake occurred at 11:34 pm on December 20, 2017 (or in UTC time, December 21 at 4:34 am) and was felt by people in the White River Junction area. A small earthquake was also felt in western Vermont on June 30, 2017. Although earthquakes are not common in Vermont, people should be prepared to "DROP, COVER and HOLD ON" during a seismic event. For preparedness information, visit Ready.gov.
What is an earthquake? It is sudden shaking of the earth caused by shifting of rock beneath the surface.
Where do earthquakes occur? 98% of earthquakes occur at plate boundaries; in the US, most occur west of the Rocky Mountains.
What should people do during an earthquake? "Drop, Cover and Hold On!"
You may notice gentle shaking, swaying of plants, or rattling of windows. Most injuries are caused by flying glass, broken chimneys or fire from ruptured gas lines and downed power lines. There is usually an aftershock. R. Allen of the Berkeley Seismological Laboratory estimated that the number of injuries could be halved if people would drop, cover and hold on (EOS, Oct 24, 2019).
What are the largest events centered in Vermont?
|date||time||lat (n)||long (W)||mag.||mmi||epicenter|
|04/10/1962||9:30 am||44.11||72.97||4.1||V||Middlebury, VT|
|07/06/1943||5:10 pm||44.84||73.03||4.1||IV||Swanton, VT|
|03/31/1953||7:59 am||43.07||73.00||4.0||V||Brandon, VT|
Town and Quadrangle Seismic Hazard Projects in Vermont: Since 1997 the Geological Survey has partnered with DEMHS, UVM, FEMA, Norwich University, NESEC and others to conduct studies and outreach which serve to inform Vermonters and assist with emergency preparedness. Completed projects include site class, amplification and liquefaction hazard maps, seismic vulnerability of critical facilities, HAZUS damage assessments, and outreach to local government, private engineering firms and the general public. The State Geologist serves as Vermont's National Earthquake Program Manager.
Seismic site class, amplification and liquefeaction hazard mapping for the Burlington and Colchester VT 7.5 minutes quadrangles, 2011
Washington County, Vermont Multi-Hazard Analysis, NESEC report, 2018
Unreinforced Masonry Buildings, Chittenden County, NESEC Report 2018
Chittenden County, Vermont Multi-Hazard Analysis, NESEC 2019