All earthquakesMontana

Montana earthquakes in 1975

35 earthquakes of magnitude 2.5 or more were located in Montana in 1975. The largest: M5.9 26 km SSE of Mammoth, Wyoming, Jun 30, 1975.

From the USGS catalog. Times are local to each quake.

19741976

Map

Where every quake of 1975 was located in Montana. Select one for its page.

Open the live map with earthquakes

Every quake of 1975

Magnitude 2.5 and up, newest first.

The largest

The 25 largest of 1975 in Montana.

Month by month

Counted by UTC date, which is how the catalog files them.

MonthQuakesLargestWhere
January 197534.413 km NNW of Old Agency, Montana
February 197524.612 km E of Evergreen, Montana
March 19750
April 197513.832 km ENE of Leadore, Idaho
May 197523.90 km NE of Toston, Montana
June 197595.926 km SSE of Mammoth, Wyoming
July 1975134.814 km SE of Mammoth, Wyoming
August 19750
September 197513.98 km ENE of Froid, Montana
October 197514.32 km S of Evergreen, Montana
November 197513.49 km SW of Logan, Montana
December 197522.835 km NE of Seeley Lake, Montana

What this means

The catalog is only as complete as the instruments of the time. Worldwide coverage of magnitude 5 and up dates from the 1960s, and of 4.5 from the 1990s; earlier years hold the large quakes and the ones near a station, so a low count in an early year means fewer instruments, not a quiet earth.

By year

Every year the USGS catalog covers.

Nearby

Montana nowWorldwide in 1975

Sources

Earthquakes, magnitudes, depths, shaking estimates and felt reports from the U.S. Geological Survey Earthquake Hazards Program, read from its live feeds and its catalog back to 1900. Tsunami messages from NOAA’s tsunami warning centers.