By Jane Feehan
Though Florida ties North Dakota for fewest earthquakes in the nation, they do occur in the Sunshine State. Also, several significant out-of-state quakes have affected Floridians including a 5.9 intraplate quake in the eastern Gulf of Mexico in 2006.
Florida does not sit within tectonic boundaries. It falls outside the Caribbean tectonic plate. But according to a 2000 news story, University of Florida geologist Doug Smith reported there have been about 500 quakes during the past 200 years in the state.
The first recorded tremor of significance occurred near Pensacola in 1780 but scientists seem to agree that the strongest recorded Florida quake occurred Jan. 12, 1879. Two tremors, 30 seconds each, “possibly centered in the Palatka area” were felt in Cedar Key (where someone shot off a gun after running outside), Gainesville, Jacksonville, St. Augustine and Tallahassee.
The southern boundary of the shaking was Punta Rassa to Daytona Beach; the northern area affected was Tallahassee to Savannah, Ga. The tremor was classified a 6 to 8 (I’m not sure if that was on the Richter magnitude scale or the modified Mercalli scale but they are not far apart and I’m not a scientist).
Two notable quakes were not centered in but affected Florida:
Jan. 22, 1880 - A Cuba-centered quake sent shockwaves to Key West with an estimated intensity of 8.
Aug. 31, 1886 - One of the nation’s most significant earthquakes rattled a wide swath of the nation from Milwaukee, Chicago, Boston, south to New Orleans and Florida. Known as the Great Charleston Earthquake, it killed up to 60 and caused millions of dollars in damage. Some reports indicate a “tidal wave” generated by this quake hit Florida, pushing water up the St. Johns River. Severe aftershocks were felt in Jacksonville days and months following the August 1886 event. South Carolina sits within the interior of the North American plate, away from any plate boundary. Little is known about the cause of such an intraplate earthquake. (As of this writing, March 2022, a swarm of small quakes have some sitting on edge in South Carolina.)
No quakes above an intensity of 3.0 were recorded from 2010-2015. However, most since then—particularly in 2019—have occurred near the Alabama-Florida border and measured as 3 or lower.
Copyright © 2022 All rights reserved. Jane Feehan
*Based on similar map
concepts by Ixnayonthetimmay, CC BY-SA 3.0,
https://commons.wikimedia.org/w/index.php?curid=2687687
Sources:
University Of Florida news - Jan. 11, 2000
University of Florida Digital Collection, History of Florida Geology, Jan. 26, 2019
Tallahassee Democrat, April 5, 1964
Miami Herald, Jan. 24, 1994
South Carolina Emergency Management Division
U.S. Geological Survey
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| Palatka By Arkyan - "My own work, based on public domain information"*. |
Two notable quakes were not centered in but affected Florida:
Jan. 22, 1880 - A Cuba-centered quake sent shockwaves to Key West with an estimated intensity of 8.
Aug. 31, 1886 - One of the nation’s most significant earthquakes rattled a wide swath of the nation from Milwaukee, Chicago, Boston, south to New Orleans and Florida. Known as the Great Charleston Earthquake, it killed up to 60 and caused millions of dollars in damage. Some reports indicate a “tidal wave” generated by this quake hit Florida, pushing water up the St. Johns River. Severe aftershocks were felt in Jacksonville days and months following the August 1886 event. South Carolina sits within the interior of the North American plate, away from any plate boundary. Little is known about the cause of such an intraplate earthquake. (As of this writing, March 2022, a swarm of small quakes have some sitting on edge in South Carolina.)
No quakes above an intensity of 3.0 were recorded from 2010-2015. However, most since then—particularly in 2019—have occurred near the Alabama-Florida border and measured as 3 or lower.
Copyright © 2022 All rights reserved. Jane Feehan
*Based on similar map
concepts by Ixnayonthetimmay, CC BY-SA 3.0,
https://commons.wikimedia.org/w/index.php?curid=2687687
Sources:
University Of Florida news - Jan. 11, 2000
University of Florida Digital Collection, History of Florida Geology, Jan. 26, 2019
Tallahassee Democrat, April 5, 1964
Miami Herald, Jan. 24, 1994
South Carolina Emergency Management Division
U.S. Geological Survey
Tags: Florida earthquakes, Florida history