QuakeIndex

Fault · Montana

Mission fault

104 kmlong (65 mi), as mapped
0.2–1 mm/yrhow fast it slips
< 15,000 yearssince it last broke the surface
10quakes of M2.5+ within 10 km since 2016

In plain English

The two sides move 0.2 to 1 mm a year — 2 to 10 cm every century.

Its most recent surface rupture is younger than 15,000 years.

USGS maps it as 2 sections: Flathead Lake section, Mission Valley section.

This week vs. its last ten years

Too quiet to rank: fewer than half a year's worth of weeks with any M1.5+ quake within 5 km, in ten years. A single quake here would read as "unusual", so we do not score it.

Computed from the USGS catalogue · a description of the past, not a forecast · method

The Mission fault as mapped at the surface (glowing), with the other mapped faults nearby, 10 of the M2.5+ earthquakes within 10 km of it since 2016 (dots), . Traces: USGS Quaternary Fault and Fold Database. Historic epicentres are estimates.

Every year since 2016

Earthquakes of M2.5+ with an epicentre within 10 km of the mapped trace. Near is not the same as on: some will have slipped on neighbouring faults.

Most recent near it

  1. M 2.6 13 km ESE of Kicking Horse, Montana
    2026-01-19 · 7 km from the trace
  2. M 2.5 6 km WNW of Bear Dance, Montana
    2022-07-14 · 1 km from the trace
  3. M 2.5 2 km WSW of Bear Dance, Montana
    2021-10-24 · 1 km from the trace
  4. M 2.7 13 km E of Ronan, Montana
    2020-01-29 · 7 km from the trace
  5. M 2.5 3 km W of Bear Dance, Montana
    2019-08-27 · 0 km from the trace
  6. M 2.5 4 km E of Lakeside, Montana
    2018-01-22 · 2 km from the trace

Fault trace, slip rate and age: USGS Quaternary Fault and Fold Database (public domain), simplified for the web. Earthquakes: USGS ComCat. QuakeIndex does not forecast earthquakes; a fault's history describes the past. For early warning use ShakeAlert.