Significant Earthquake

Date Earthquake Location Earthquake Parameters
Focal
Depth
Magnitude MMI Int
Year Mo Dy Hr Mn Sec Name Latitude Longitude Mw Ms Mb Ml Mfa Unk
1959 8 18 6 37 13.5 MONTANA: HEBGEN LAKE 44.712 -111.215 5 7.7 7.1 10
Significant Earthquake
Earthquake Effects Total Effects (Earthquake and Tsunami, Volcano, etc.)
Deaths Missing Injuries Damage Houses
Destroyed
Houses
Damaged
Deaths Missing Injuries Damage Houses
Destroyed
Houses
Damaged
Num De Num De Num De $Mill De Num De Num De Num De Num De Num De $Mill De Num De Num De
28 1 11.000 3 28 1 11.000 3


Comments for the Significant Earthquake

Comments for the Significant Earthquake

Display listing of nearby significant earthquakes

This earthquake caused 28 fatalities and about $11 million damage to highways and timber. It is characterized by extensive fault scarps, subsidence and uplift, a massive landslide, and a seiche in Hebgen Lake. A maximum MM intensity X was assigned to the fault scarps in the epicentral area. The instrumental epicenter lies within the region of surface faulting. The most spectacular and disastrous effect of the earthquke was the huge avalanche of rock, soil, and trees that cascaded from the steep south wall of the Madison River canyon. This slide formed a barrier that blocked the gorge and stoped the flow of the Madison River and within a few weeks, created a lake almost 53 m deep. The volume of material that blocked the Madison River below Hebgen Dam has been estimated at 28-33 million m3. Most of the 28 deaths were caused by rockslides that covered the Rock Creek public campground on the Madison River, about 9.5 km below Hebgen Dam.

New fault scarps as high as 6 m formed near Hebgen Lake. The major fault scarps formed along pre-existing normal faults northeast of Hebgen Lake. Subsidence ocurred over much of an area that was about 24 km north-south and about twice as long east-west. As a result of the faulting near Hebgen Lake, the bedrock beneath the lake was permanently warped, causing the lake floor to drop and generate a seiche. Maximum subsidence was 6.7 m in Hebgen Lake Basin. About 130 km2 subsided more than 3 m, and about 500 km2 subsided more than 0.3 m. The earth-fill dam sustained significant cracks in its concrete core and spillway, but it continued to be an effective structure.

Many summer houses in the Hebgen Lake area were damaged: houses and cabins shifted off their foundations, chimneys fell, and pipeines broke. Most small-unit masonry structures and wooden buildings along the major fault scarps survived with little damage when subjected only to vibratory forces. Roadways were cracked and shifted extensively, and much timber was destroyed. Highway damage near Hebgen Lake was due to landslides slumping vertically and flowing laterally beneath pavements and bridges, which caused severe cracks and destruction. Three of the five reinforced bridges in the epicentral area also sustained significant damage.

High intensities were observed in the northwest section of Yellowstone National Park. Here, new geysers erupted and massive slumping caused large cracks in the ground from which steam emitted. Many hot springs became muddy.
(above from reference #542)

Reference #1250 lists $26 million dollars damage.


References for the Significant Earthquake

References for the Significant Earthquake

ID Author Year Citation
45 U.S. Department of the Interior, Geological Survey and U.S. Department of Commerce, National Oceanic and Atmospheric Administration 1928-1986 United States Earthquakes, Annual publication, published 1928-1986. vol.s for 1928-1965 issued by the U.S. Coast and Geodetic Survey; volumes for 1966-1969 issued by the National Earthquake Information Center; volume for 1970 issued by the National Geophysical Data Center; volumes for 1971-1972 issued by the National Geophysical And Solar-Terrestrial Data Center; volumes for 1973-1980 published jointly by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Geological Survey; volumes for 1981-1986 published by the U.S. Geological Survey. [on shelf]
1128 Coffman, J.L. and C.A. von Hake 1973-1982 Earthquake History of the United States, Pub. 41-1, U.S. Department of Commerce, Boulder, CO, 1973, and 1982 Supplement.
1250 Centre for Research on the Epidemiology of Disasters (CRED) and the U.S. Office of Foreign Disaster Assistance (OFDA) 2001 EM-DAT: The OFDA/CRED International Disaster Database, Universite Catholique de Louvain, Brussels, Belgium, link
3656 Tebbe, Charles L. 1959 Hebgen Lake - Madison River Earthquake Disaster, August 1959, Gallatin - Beaverhead National Forests (Montana). U.S. Department of Agriculture, Forest Service, 50 p.
3657 Coast and Geodetic Survey 1959 Preliminary Report: Hebgen Lake, Montana Earthquakes, August 1959. U.S. Department of Commerce, Coast and Geodetic Survey, Washington, D.C., 20 p.
3658 Steinbrugge, Karl V. and William K. Cloud 1962 Epicentral intensities and damage in the Hebgen Lake, Montana, earthquake of August 17, 1959. Bulletin of the Seismological Society of America, vol. 52, no. 2, p. 181-234.