Earthquake Hits Northeastern Illinois

An earthquake hit right before 4 a.m., February 10, 2010, about 2 miles northwest of Lily Lake in Kane County and was located about 6 miles below the ground surface. This would be in the layers of granite below Chicago. The magnitude was first reported as 4.3 but was later downgraded to 3.8. The earthquake was felt in 8 states and was reported by about 18,000 people.

Counties surrounding this area have about 5 earthquakes historically:
      DuPage in 1985, magnitude 3.0
      Kane in 1944, magnitude 2.7 and in 1947, 3.1
      Kendall in 1912, magnitude 4.7
      Will in 1909, magnitude 5.1, which caused damage and fires

The last one Chicago felt was on June 28, 2004 in LaSalle County with a magnitude of 4.2.
      Poster of the Northern Illinois Earthquake of 28 June 2004 - Magnitude 4.2

See the US Geological Survey Web site for information on this earthquake:
      Magnitude 3.8 - Illinois

Earthquake's Orgins Remain a Mystery - Chicago Tribune article that quotes ISGS staff member Tim Larson

Updated 02/22/2010 SLD