1947 Wisconsin earthquake

1947 Wisconsin earthquake
UTC time	1947-05-06 20:25
ISC event	n/a
USGS-ANSS	n/a
Local date	May 6, 1947
Local time	15:25 (CST)[ citation needed ]
Magnitude	No record
Epicenter	43°03′N87°57′W / 43.05°N 87.95°W
Max. intensity	V (Moderate)

Last updated October 10, 2023

The 1947 Wisconsin earthquake took place on May 6, immediately south of Milwaukee at 15:25 (CST). It was the largest tremor to be historically documented in Wisconsin, but was not recorded by seismographs.

History

The area had been previously shaken by the 1909 Wabash River earthquake, causing damage assessed at VII (Very strong) on the Modified Mercalli scale across the Wisconsin-Illinois border. Two earthquakes were also reported in the state in 1912. Shocks in 1919 and 1925, the first from Missouri and the latter from Canada, occurred over enormous zones and affected the entire region, though not seriously. Earthquakes struck Wisconsin again in 1937 and 1939.^[1]

Damage

The area hardest hit was a 7,770 square kilometers (3,000 sq mi) strip of land in southeastern Wisconsin, while the earthquake was felt over a much more extensive 99 miles (159 km) wide area stretching across the Wisconsin-Illinois border, and to Lake Michigan and Waukesha. Damage consisted of broken windows and fallen porcelain, pots and dishes.^[2] The locals' initial impression was that an explosion had taken place. Many evacuated buildings into the streets.^[2] Corporate office buildings were emptied of workers.^[3] Numerous calls were made local fire departments, police stations and newspapers. Three reports were made to the Milwaukee Fire Department, all describing explosions.^[3]

Often described as "sharp", this was the most powerful earthquake to date in Wisconsin's seismological history. The earthquake broke a seismograph at Marquette University.^[3] Many hotels, such as the Schroeder Hotel in Milwaukee, were rocked by the tremor. However, the earthquake caused no serious damage or casualties.^[3]

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References

1 2 "Wisconsin: Earthquake History". United States Geological Survey. January 30, 2009. Archived from the original on 2009-03-26. Retrieved May 6, 2009.
1 2 "Today in Earthquake History: May 6". United States Geological Survey. January 30, 2009. Retrieved May 6, 2009.
1 2 3 4 "Sharp Earthquake Rocks Buildings in Milwaukee". Saint Petersburg Times. May 6, 1947. Retrieved May 8, 2009.

v t e Earthquakes in the United States
Historical	1585 Aleutian Islands 1638 New Hampshire 1663 Charlevoix 1700 Cascadia 1755 Cape Ann 1811–12 New Madrid 1812 San Juan Capistrano 1812 Santa Barbara 1838 San Andreas 1857 Fort Tejon 1865 Memphis 1867 Manhattan, Kansas 1868 Hawaii 1868 Hayward 1870 Charlevoix 1871 Lānaʻi 1872 Owens Valley 1872 North Cascades 1886 Charleston 1887 Sonora 1892 Laguna Salada 1892 Vacaville–Winters 1895 Charleston 1898 Mare Island 1899 San Jacinto
20th-century	1901 Richfield 1906 San Francisco 1906 Aleutian Islands 1909 Wabash River 1914 Reno 1915 Imperial Valley 1915 Pleasant Valley 1916 Irondale 1918 San Jacinto 1921 Sevier Valley 1925 Montana 1925 Santa Barbara 1927 Lompoc 1931 Valentine 1932 Eureka 1932 Cedar Mountain 1933 Long Beach 1934 Hansel Valley 1935 Helena 1936 State Line 1940 El Centro 1940 New Hampshire 1944 Cornwall–Massena 1946 Aleutian Islands 1947 Wisconsin 1948 Desert Hot Springs 1949 Olympia 1952 Kern County 1954 Churchill County 1957 Andreanof Islands 1957 San Francisco 1958 Huslia 1958 Lituya Bay 1959 Hebgen Lake 1962 Cache Valley 1964 Alaska 1965 Rat Islands 1965 Puget Sound 1968 Borrego Mountain 1968 Illinois 1969 Santa Rosa 1971 San Fernando 1973 Point Mugu 1975 Near Islands 1975 Morris 1975 Hawaii 1979 Coyote Lake 1979 Imperial Valley 1980 Eureka 1981 Westmorland 1983 Coalinga 1983 Borah Peak 1983 Kaoiki 1984 Morgan Hill 1986 North Palm Springs 1986 Chalfant Valley 1987 Whittier Narrows 1987 Imperial Valley 1989 Loma Prieta 1990 Upland 1991 Sierra Madre 1992 Joshua Tree 1992 Cape Mendocino 1992 Landers 1992 Big Bear 1992 St. George 1993 Scotts Mills 1993 Klamath Falls 1994 Northridge 1995 Marathon 1998 Pymatuning 1999 Hector Mine 2000 Yountville
21st-century	2001 Nisqually 2002 Denali 2003 Alabama 2003 San Simeon 2006 Gulf of Mexico 2006 Kiholo Bay 2008 Illinois 2008 Chino Hills 2008 Reno 2008 Wells 2010 Eureka 2010 Baja California 2010 Indiana 2011 Colorado 2011 Virginia 2011 Oklahoma 2013 Port Alexander 2014 La Habra 2014 Aleutian Islands 2014 Southeast Alaska 2014 South Napa 2016 Oklahoma 2018 Alaska 2018 Hawaii 2018 Anchorage 2018 Southern Appalachian 2019 Ridgecrest 2020 Salt Lake City 2020 Central Idaho 2020 Monte Cristo Range 2020 Sparta 2021 Chignik 2022 Ferndale
Swarms	2001 Enola 2008 Reno 2010–11 Guy-Greenbrier 2012 Brawley 2009–present Oklahoma 2019 Ridgecrest

1947 Wisconsin earthquake

Contents

History

Damage

See also

Related Research Articles

References

Further reading