Fault · Alaska

Ragged Mountain fault

30 kmlong (19 mi), as mapped

1–5 mm/yrhow fast it slips

< 15,000 yearssince it last broke the surface

0quakes of M2.5+ within 10 km since 2016

In plain English

The two sides move 1 to 5 mm a year — 10 to 50 cm (4 to 20 inches) every century.

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

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 2026-09-28 23:45 UTC from the USGS catalogue · a description of the past, not a forecast · method

The Ragged Mountain fault as mapped at the surface (glowing), with the other mapped faults nearby, . Traces: USGS Quaternary Fault and Fold Database. Historic epicentres are estimates.

Neighbouring faults

Wingham fault 27 km away
Kayak fault 34 km away
Ten Fathom fault 40 km away

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.