M1.8 earthquake 23 km SSW of Mammoth, Wyoming

Magnitude

1.8 (ML, local (Richter)), micro

Magnitude from

University of Utah Seismograph Stations

Local time

Wed, Aug 29, 2018, 11:42 AM MDT

UTC

2018-08-29 17:42:10 UTC

Depth

5.0 km (3.1 mi), shallow

Epicenter

44.777° N, 110.793° W

Region

Montana

Tsunami flag

No

Status

Reviewed by a seismologist

Location uncertainty

About 0.4 km horizontally, 0.6 km in depth

Magnitude uncertainty

±0.30

Depth from

From location

Station coverage gap

90°

Stations used

18

• West Yellowstone, MontanaPopulation 1,339. Forecast28 kmENE
• Bozeman, MontanaPopulation 43,405. Forecast102 kmS
• Billings, MontanaPopulation 117,116. Forecast211 kmWSW
• Calgary, CanadaPopulation 1,306,784. Forecast739 kmSSE

After

1. 2.323 km SSW of Mammoth, WyomingWed, Aug 29, 12:07 PM MDT · 2955 days ago · 5 km deep · 0 km away
2. 2.423 km SSW of Mammoth, WyomingWed, Aug 29, 1:44 PM MDT · 2955 days ago · 5 km deep · 1 km away
3. 2.222 km SSW of Mammoth, WyomingWed, Aug 29, 9:55 PM MDT · 2954 days ago · 5 km deep · 1 km away
4. 1.545 km SSE of Mammoth, WyomingTue, Sep 4, 6:10 PM MDT · 2948 days ago · 4 km deep · 34 km away
5. 1.639 km S of Silver Gate, MontanaFri, Sep 7, 6:50 AM MDT · 2946 days ago · 13 km deep · 62 km away
6. 1.640 km S of Silver Gate, MontanaFri, Sep 7, 2:43 PM MDT · 2946 days ago · 10 km deep · 61 km away
7. 1.944 km W of Hebgen Lake Estates, MontanaMon, Sep 10, 3:08 AM MDT · 2943 days ago · 10 km deep · 75 km away
8. 2.925 km ESE of Mammoth, WyomingTue, Sep 11, 7:30 AM MDT · 2942 days ago · 11 km deep · 30 km away
9. 2.035 km ESE of Island Park, IdahoThu, Sep 13, 7:59 AM MDT · 2940 days ago · 4 km deep · 49 km away
10. 1.714 km S of West Yellowstone, MontanaSun, Sep 16, 1:51 PM MDT · 2937 days ago · 13 km deep · 36 km away
11. 1.754 km SE of West Yellowstone, MontanaWed, Sep 19, 8:44 AM MDT · 2934 days ago · 6 km deep · 50 km away
12. 1.647 km ENE of Warm River, IdahoTue, Sep 25, 11:26 AM MDT · 2928 days ago · 11 km deep · 59 km away
13. 1.910 km ESE of Bozeman, MontanaThu, Sep 27, 1:20 PM MDT · 2926 days ago · 4 km deep · 97 km away
14. 1.734 km S of Silver Gate, MontanaSat, Sep 29, 12:47 PM MDT · 2924 days ago · 17 km deep · 64 km away
15. 2.713 km NE of West Yellowstone, MontanaThu, Oct 4, 2:47 AM MDT · 2919 days ago · 10 km deep · 15 km away
16. 2.323 km SW of Mammoth, WyomingThu, Oct 4, 11:50 PM MDT · 2918 days ago · 7 km deep · 8 km away
17. 1.746 km ENE of Warm River, IdahoSat, Oct 6, 6:31 AM MDT · 2917 days ago · 4 km deep · 60 km away
18. 1.531 km ESE of Island Park, IdahoSat, Oct 6, 10:44 PM MDT · 2916 days ago · 8 km deep · 49 km away
19. 1.545 km SSE of Mammoth, WyomingMon, Oct 8, 5:38 AM MDT · 2915 days ago · 2 km deep · 34 km away
20. 1.711 km NNE of Tetonia, IdahoTue, Oct 9, 9:15 AM MDT · 2914 days ago · 11 km deep · 99 km away · felt by 1
21. 1.745 km ENE of Warm River, IdahoWed, Oct 10, 2:52 PM MDT · 2913 days ago · 6 km deep · 56 km away
22. 2.610 km NNE of West Yellowstone, MontanaSat, Oct 13, 7:52 AM MDT · 2910 days ago · 7 km deep · 20 km away
23. 1.53 km ESE of Big Sky, MontanaMon, Oct 15, 4:14 AM MDT · 2908 days ago · 13 km deep · 69 km away
24. 2.011 km NNE of West Yellowstone, MontanaMon, Oct 15, 1:45 PM MDT · 2908 days ago · 7 km deep · 19 km away
25. 2.212 km NNE of West Yellowstone, MontanaTue, Oct 16, 2:37 AM MDT · 2907 days ago · 9 km deep · 19 km away
26. 1.818 km NE of West Yellowstone, MontanaFri, Oct 19, 6:43 PM MDT · 2903 days ago · 9 km deep · 11 km away
27. 1.518 km NE of West Yellowstone, MontanaFri, Oct 19, 6:57 PM MDT · 2903 days ago · 9 km deep · 11 km away
28. 2.772 km ESE of West Yellowstone, MontanaSun, Oct 21, 3:07 PM MDT · 2901 days ago · 10 km deep · 61 km away · felt by 1
29. 2.123 km SW of Mammoth, WyomingMon, Oct 22, 4:20 PM MDT · 2900 days ago · 5 km deep · 8 km away
30. 1.646 km SE of West Yellowstone, MontanaWed, Oct 24, 4:56 PM MDT · 2898 days ago · 3 km deep · 45 km away

Before

1. 2.545 km NNE of Spencer, IdahoMon, Aug 27, 2:22 AM MDT · 2957 days ago · 5 km deep · 99 km away
2. 2.047 km ESE of West Yellowstone, MontanaSun, Aug 26, 2:55 PM MDT · 2958 days ago · 4 km deep · 38 km away
3. 2.047 km ESE of West Yellowstone, MontanaSun, Aug 26, 2:45 PM MDT · 2958 days ago · 4 km deep · 39 km away
4. 1.747 km ESE of West Yellowstone, MontanaSun, Aug 26, 2:36 PM MDT · 2958 days ago · 4 km deep · 38 km away
5. 1.7WyomingSun, Aug 26, 2:33 PM MDT · 2958 days ago · 4 km deep · 38 km away
6. 1.647 km ESE of West Yellowstone, MontanaSun, Aug 26, 2:32 PM MDT · 2958 days ago · 4 km deep · 39 km away
7. 1.947 km ESE of West Yellowstone, MontanaSun, Aug 26, 2:27 PM MDT · 2958 days ago · 4 km deep · 38 km away
8. 1.849 km ESE of West Yellowstone, MontanaTue, Aug 21, 2:02 AM MDT · 2963 days ago · 6 km deep · 40 km away
9. 1.513 km E of Hebgen Lake Estates, MontanaFri, Aug 17, 4:30 AM MDT · 2967 days ago · 10 km deep · 18 km away
10. 1.6Idaho-Montana border regionFri, Aug 17, 12:13 AM MDT · 2967 days ago · 10 km deep · 18 km away
11. 1.845 km ENE of Warm River, IdahoWed, Aug 15, 11:17 PM MDT · 2968 days ago · 7 km deep · 58 km away
12. 2.144 km W of Hebgen Lake Estates, MontanaFri, Aug 10, 11:22 AM MDT · 2974 days ago · 11 km deep · 76 km away
13. 1.717 km ENE of Hebgen Lake Estates, MontanaFri, Aug 10, 10:58 AM MDT · 2974 days ago · 11 km deep · 15 km away
14. 2.536 km S of Silver Gate, MontanaTue, Aug 7, 4:19 AM MDT · 2977 days ago · 15 km deep · 60 km away
15. 1.65 km E of Hebgen Lake Estates, MontanaFri, Aug 3, 3:32 PM MDT · 2980 days ago · 10 km deep · 26 km away
16. 1.65 km E of Hebgen Lake Estates, MontanaFri, Aug 3, 3:14 PM MDT · 2980 days ago · 10 km deep · 26 km away
17. 2.15 km E of Hebgen Lake Estates, MontanaThu, Aug 2, 11:28 PM MDT · 2981 days ago · 11 km deep · 26 km away
18. 2.15 km E of Hebgen Lake Estates, MontanaThu, Aug 2, 10:46 PM MDT · 2981 days ago · 11 km deep · 26 km away
19. 1.756 km SSW of Silver Gate, MontanaThu, Aug 2, 7:16 PM MDT · 2981 days ago · 6 km deep · 58 km away

From the USGS Earthquake Hazards Program and its partner networks, event uu60294802. Read Thu, Oct 1, 2026, 8:29 AM UTC.