1992 St. George earthquake

The 1992 St. George earthquake was a Mw5.8 earthquake that occurred on September 2, 1992 at approximately 4:26 AM MDT along the Washington Fault zone near the larger Hurricane Fault about 5 miles (8.0 km) southeast of St. George in Utah, United States. The quake triggered a landslide that destroyed three houses and caused approximately US$1 million in structural and cosmetic damage to houses, roads, natural formations, and utilities. No people were killed by the quake.

1992 St. George earthquake
1992 St. George earthquake is located in Utah
Salt Lake City
Salt Lake City
1992 St. George earthquake
UTC time1992-09-02 10:26
ISC event271074
USGS-ANSSComCat
Local dateSeptember 2, 1992 (1992-09-02)
Local time04:26 a.m. MDT
Magnitude5.8 Mw
Depth13.9 km (8.6 mi)
Epicenter37°06′00″N 113°29′49″W / 37.1°N 113.497°W / 37.1; -113.497
FaultHurricane Fault
Areas affectedUtah, southern Nevada, northwest Arizona
Total damageUS$1 million
Max. intensityMMI VII (Very strong)
Peak acceleration0.233 g
Peak velocity2.998 cm/s
CasualtiesNone

Earthquake

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At 4:26 AM MDT on September 2, 1992, a magnitude 5.8 earthquake occurred along the Washington Fault zone near the larger Hurricane Fault about 5 miles (8.0 km) southeast of St. George in Utah, United States.[1]

Magnitude

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Reports on the magnitude of the earthquake vary.[1][2][3] The University of Utah reported the quake as a Mw5.8 in their official report via the Intermountain Seismic Belt Historical Earthquake Project,[4] which is supported by a 1994 news article from the Deseret News[5] and an official report from the Utah Geological Survey.[6] A contemporaneous report from the journal Arizona Geology reported Mw5.5 from the University of Arizona and Mw5.9 from the USGS.[1]

Destruction

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Most of the force of the earthquake was directed away from the city of St. George toward Hurricane and Springdale.[5] In the Balanced Rock Hills area of Springdale, a landslide covered part of Utah State Route 9, taking several hours to complete movement.[6] The slide was about 1,600 feet (490 m) long and 3,600 feet (1,100 m) wide, contained boulders up to 20 feet (6.1 m) in diameter, with a total volume of 18,000,000 cubic yards (14,000,000 m3) and total area of 4,400,400 square feet (408,810 m2).[2][6] It destroyed three houses as well as above- and below-ground utilities, causing about US$1 million in damage.[5][6]

See also

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References

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  1. ^ a b c Pearthree, Philip A.; Wallace, Terry C. (Winter 1992). "The St. George Earthquake of September 2, 1992" (PDF). Arizona Geology. 22 (4): 7–8. Archived (PDF) from the original on December 28, 2017. Retrieved March 18, 2020.
  2. ^ a b "Southwest Utah Is Jolted by Early-Morning Quake". Deseret News. Associated Press. September 3, 1992. Archived from the original on March 18, 2020. Retrieved March 18, 2020.
  3. ^ Rowe, Gina (March 18, 2020). "A history of Utah's largest earthquakes". KUTV. Archived from the original on March 18, 2020. Retrieved March 18, 2020.
  4. ^ Peterson, Sheryl. "1992 – St. George, UT – M 5.8". University of Utah. Archived from the original on March 18, 2020. Retrieved March 18, 2020.
  5. ^ a b c "'92 quake left St. George virtually unshaken". Deseret News. Associated Press. May 15, 1994. Archived from the original on March 18, 2020. Retrieved March 18, 2020.
  6. ^ a b c d Christenson, Gary E., ed. (1995). The September 2, 1992 ML 5.8 St. George Earthquake, Washington County, Utah (PDF). Utah Geological Survey. ISBN 1-55791-367-6. Archived (PDF) from the original on December 13, 2016. Retrieved March 18, 2020.