Intermountain Seismic Belt Historical Earthquake Project

Overview

The Intermountain Seismic Belt Historical Earthquake Project is a compilation of newspaper articles, photographs, personal accounts, and scientific details of 48 historic earthquakes along the Intermountain Seismic Belt (ISB) within Montana, Wyoming, Idaho (magnitude 5.5 and larger), and Utah (magnitude 5.0 and larger).  The effort is intended to personalize earthquake risk to current residents in the ISB by presenting evidence of the real impact to people and places from past ISB earthquakes. The purpose is to promote better understanding of the earthquake threat of this region and to motivate individuals to prepare for future earthquakes.isb_quakes

Earthquakes Researched for this Project

(Magnitude Explanations)

1. 1945 Flathead Lake, MT  M 5.5 25. 1943 Magna, UT  M 5.0
2. 1952 Big Fork, MT  M 5.5 26. 1962 Magna, UT  M 5.2
3. 1935 Helena, MT (series)  M 6¼ 27. 1958 Wallsburg, UT  M 5.0
4. 1928 Helena, MT  M 5½ ± 28. 1915 Provo, UT  M 5.0
5. 1929 Lombard, MT  M 5.6 29. 1900 Eureka, UT  M 5½
6. 1925 Clarkston Valley, MT  M 6¾ 30. 1876 Moroni, UT  M 5.0
7. 1947 Virginia City, MT  M 6¼ 31. 1961 Ephraim, UT  M 5.0
8. 1959 Hebgen Lake, MT (series)  M 7.5 32. 1988 San Rafael Swell, UT  M 5.3
9. 1975 Yellowstone National Park, WY  M 6.1 33. 1989 So. Wasatch Plateau, UT  M 5.4
10. 1945 Central Idaho  M 6.0 34. 1901 Southern Utah  M 6½
11. 1944 Central Idaho  M 6.1 35. 1945 Glenwood, UT  M 5.0
12. 1983 Borah Peak, ID (series)  M 7.3 36. 1910 Elsinore, UT (series)  M 5.0
13. 1905 Shoshone, ID  M 5½ 37. 1921 Elsinore, UT (series)  M 6±
14. 1994 Draney Peak, ID  M 5.9 38. 1967 Marysvale, UT  M 5.2
15. 1930 Grover, WY  M 5.8 39. 1908 Milford, UT  M 5.0
16. 1975 Pocatello Valley, ID  M 6.0 40. 1959 Panguitch, UT  M 5.0
17. 1962 Cache Valley, UT  M 5.7 41. 1933 Parowan, UT  M 5.0
18. 1884 Bear Lake, ID  M 6.3 42. 1942 Cedar City, UT  M 5.0
19. 1909 Hansel Valley, UT  M 6± 43. 1942 Cedar City, UT  M 5.0
20. 1934 Hansel Valley, UT (series)  M 6.6 44. 1902 Pine Valley, UT (series)  M 6±
21. 1914 Ogden, UT  M 5½ 45. 1992 St. George, UT  M 5.8
22. 1894 Ogden, UT  M 5.0 46. 1891 St. George, UT  M 5.0
23. 1910 Salt Lake City, UT  M 5½ 47. 1887 Kanab, UT  M 5.7
24. 1949 Salt Lake City, UT  M 5.0 48. 1959 Kanab, UT  M 5.7

View earthquake list sorted by date, magnitude, intensity.
Many of the earthquakes above have been reanalyzed since the original project (see Arabasz and others, 2016).

Information Available

Each earthquake highlighted above is linked to a blog post (published periodically) containing further details.  Blog posts feature a map of the earthquake location, a brief overview of the earthquake, and links to:

Earthquake Summary – scientific details (name, date, time, location, epicenter coordinates, magnitude, intensity, and felt area) of the earthquake and of any significant aftershocks.

Newspaper Articles – transcriptions of relevant news articles gathered from a minimum of two statewide newspapers and one local newspaper.

Photographs – obtained from newspaper archives, historical societies, and individuals responding to a request printed in local newspapers.

Personal Accounts – transcriptions of accounts collected from library files, earthquake survey responses, written responses to requests printed in local newspapers, and in-person interviews.

Additional Resources – a list of reports, scientific journal articles, USGS professional papers, PhD dissertations or Masters theses, and excerpts from books published for a general public audience.

Project Credit

Originally titled Personalizing the Earthquake Threat, this project was conducted under the direction of Edith O’Brien and Susan J. Nava, principal investigators.  The original webpage was designed by Cynthia Meier.  Text revisions, web layout and format changes, and blog posts were produced by Sheryl Peterson.  Modernized maps were created by Paul Roberson.