QuakeIndex

Fault · Alaska

Park Road fault (Northern Foothills fold and thrust belt)

63 kmlong (39 mi), as mapped
0.2–1 mm/yrhow fast it slips
< 15,000 yearssince it last broke the surface
53quakes 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.

The largest earthquake recorded near it was M 6.1 in 1929 (35 km E of Healy, Alaska) — about 50,000 times the energy of an M3.0, the size people start to feel. It released about 24 kilotons of TNT.

This week vs. its last ten years

95/100

unusual

2 quakes of M1.5+ within 5 km of the trace in the last 7 days — busier than 95% of weeks since 2016. A normal week: 0–1.

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

Denali faultNorthern Foothills thrust fault (Northern Foothills fold and thrust belt) M 6.1 · 1929 · 35 km E of Healy, Alaska
The Park Road fault (Northern Foothills fold and thrust belt) as mapped at the surface (glowing), with the other mapped faults nearby, 53 of the M2.5+ earthquakes within 10 km of it since 2016 (dots), and the epicentres of the large historic earthquakes recorded near it (rings). 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 6.1 35 km E of Healy, Alaska
    January 21, 1929 · epicentre 9 km from the trace
  2. M 4.4 37 km WSW of Denali Park, Alaska
    May 9, 2023 · epicentre 9 km from the trace
  3. M 4.1 19 km WSW of Healy, Alaska
    September 25, 2019 · epicentre 6 km from the trace
  4. M 4.1 14 km WSW of Healy, Alaska
    July 11, 2016 · epicentre 9 km from the trace
  5. M 4.1 6 km ESE of Healy, Alaska
    August 24, 2022 · epicentre 10 km from the trace
  6. M 4.0 6 km SSW of Healy, Alaska
    December 30, 2017 · epicentre 9 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 7 km ENE of Denali Park, Alaska
    2026-09-28 · 2 km from the trace
  2. M 2.6 19 km WSW of Denali Park, Alaska
    2026-07-02 · 5 km from the trace
  3. M 3.5 36 km WSW of Denali Park, Alaska
    2026-03-04 · 10 km from the trace
  4. M 2.8 40 km WSW of Healy, Alaska
    2025-11-27 · 10 km from the trace
  5. M 2.5 21 km E of Healy, Alaska
    2025-11-19 · 8 km from the trace
  6. M 3.5 13 km W of Denali Park, Alaska
    2025-11-17 · 1 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.