QuakeIndex

Fault · Idaho, Utah

Eastern Bear Lake fault

78 kmlong (48 mi), as mapped
0.2–1 mm/yrhow fast it slips
< 15,000 yearssince it last broke the surface
9quakes 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 4.0 in 2017 (3 km WNW of Georgetown, Idaho) — about 32 times the energy of an M3.0, the size people start to feel. It released about 15 tons of TNT.

USGS maps it as 3 sections: central section, northern section, southern 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

Wasatch faultGrand Valley faultGreat Salt Lake faultEast Cache faultWest Cache faultWestern Bear Lake faultGreys River faultRock Creek fault
The Eastern Bear Lake fault as mapped at the surface (glowing), with the other mapped faults nearby, 9 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 4.0 3 km WNW of Georgetown, Idaho
    September 14, 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 3.2 6 km WSW of Bennington, Idaho
    2026-07-23 · 9 km from the trace
  2. M 3.0 6 km WSW of Bennington, Idaho
    2026-07-22 · 9 km from the trace
  3. M 2.6 11 km ENE of Georgetown, Idaho
    2025-09-06 · 10 km from the trace
  4. M 3.0 11 km ENE of Georgetown, Idaho
    2025-07-28 · 10 km from the trace
  5. M 2.6 1 km WSW of Bennington, Idaho
    2020-06-24 · 4 km from the trace
  6. M 4.0 3 km WNW of Georgetown, Idaho
    2017-09-14 · 9 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.