QuakeIndex

Fault · Alaska

Totschunda fault

212 kmlong (132 mi), as mapped
> 5 mm/yrhow fast it slips
last 150 yearssince it last broke the surface
24quakes of M2.5+ within 10 km since 2016

In plain English

The two sides grind past each other faster than 5 mm a year — more than half a metre (20 inches) every century.

It has broken the ground surface within the last 150 years.

The largest earthquake recorded near it was M 5.3 in 2017 (20 km NE of Nabesna, Alaska) — about 2,800 times the energy of an M3.0, the size people start to feel. It released about 1.3 kilotons of TNT.

This week vs. its last ten years

0/100

quiet

0 quakes of M1.5+ within 5 km of the trace in the last 7 days — busier than 0% of weeks since 2016. A normal week: 0–1.

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

Denali faultCathedral Rapids faults (Northern Foothills fold and thrust belt)
The Totschunda fault as mapped at the surface (glowing), with the other mapped faults nearby, 24 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.

The big ones recorded near it

  1. M 5.3 20 km NE of Nabesna, Alaska
    February 13, 2017 · epicentre 3 km from the trace
  2. M 4.1 86 km E of McCarthy, Alaska
    August 20, 2021 · epicentre 3 km from the trace
  3. M 4.1 9 km ESE of Mentasta Lake, Alaska
    July 26, 2021 · epicentre 2 km from the trace
  4. M 4.1 6 km ESE of Mentasta Lake, Alaska
    July 26, 2021 · epicentre on the trace
  5. M 4.0 4 km E of Mentasta Lake, Alaska
    October 10, 2019 · epicentre 2 km from the trace

Before 1973 from the USGS ComCat historical catalogue (within 25 km; epicentres of old earthquakes are estimates). Since 2016, M4+ within 10 km.

Most recent near it

  1. M 3.1 13 km N of Mentasta Lake, Alaska
    2026-08-28 · 9 km from the trace
  2. M 2.9 32 km ESE of Nabesna, Alaska
    2026-01-25 · 5 km from the trace
  3. M 3.1 91 km E of McCarthy, Alaska
    2025-12-31 · 7 km from the trace
  4. M 2.6 82 km E of McCarthy, Alaska
    2025-09-01 · 1 km from the trace
  5. M 3.5 91 km E of McCarthy, Alaska
    2025-08-06 · 5 km from the trace
  6. M 2.5 84 km E of McCarthy, Alaska
    2024-08-30 · 0 km from the trace

Neighbouring faults

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.