This is Your Chance to Help
Do you remember the November 9, 1968, Magnitude 5.4 southern Illinois earthquake? Did you experience shaking and do you remember where you were and what happened?
This earthquake was widely felt, and if you were living in the region at the time, it is scientifically important to note that you did or did not feel it. It was the strongest felt earthquake in southern Illinois since the M6.6 Halloween 1895 earthquake near Charleston, Mo.
In commemoration of the upcoming 45th anniversary of this important earthquake, the U.S. Geological Survey established a “Did You Feel It” site for people to record their shaking experience during this quake which was felt from Cleveland to Kansas City and Minneapolis to Atlanta.
This Isoseismal map shows lines of equal felt seismic intensity, measured on the Modified Mercalli scale. It is based on intensity estimates from data. Abridged from Seismicity of the United States, 1568-1989 (Revised), by Carl W. Stover and Jerry L. Coffman, U.S. Geological Survey Professional Paper 1527, United States Government Printing Office, Washington: 1993.
The quake occurred at about 11 a.m. local time and geologists can learn from hearing from you. Your shaking experience will be converted to an Intensity map and scientists will use this information to strengthen a study of damage and intensity that was completed soon after the earthquake by the U.S. Coast and Geodetic Survey and St. Louis University.
This USGS website will ask for your zip code — where you were that day and the address — on that day (not now). This is needed only to help identify the differences in earthquake shaking from location to location. As you work your way through the website’s queries, it will ‘automatically’ measure scientific information about what you experienced. This information is very important to today’s earthquake scientists.
