QuakeIndex

Fault · Utah

Great Salt Lake fault

103 kmlong (64 mi), as mapped
0.2–1 mm/yrhow fast it slips
< 15,000 yearssince it last broke the surface
11quakes 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 6.6 in 1934 (The 1934 Hansel Valley, Utah Earthquake) — about 250,000 times the energy of an M3.0, the size people start to feel. It released about 120 kilotons of TNT.

USGS maps it as 3 sections: Antelope Island section, Fremont Island section, Promontory 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 faultEast Cache faultWest Cache faultSkull Valley (mid-valley) faultsStansbury faultNorth Promontory faultSouthern Oquirrh Mountains faultOquirrh faultMorgan faultWest Valley faultHansel Valley fault M 6.6 · 1934 · The 1934 Hansel Valley, Utah Earthquake
The Great Salt Lake fault as mapped at the surface (glowing), with the other mapped faults nearby, 11 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 6.6 The 1934 Hansel Valley, Utah Earthquake
    March 12, 1934 · epicentre 14 km from the trace
  2. M 4.2 1 km NNW of Magna, Utah
    March 18, 2020 · 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 2.5 1 km NNE of Magna, Utah
    2022-06-03 · 10 km from the trace
  2. M 3.5 47 km SW of Howell, Utah
    2021-04-06 · 4 km from the trace
  3. M 2.9 6 km NNE of Magna, Utah
    2020-03-21 · 10 km from the trace
  4. M 2.8 2 km N of Magna, Utah
    2020-03-19 · 9 km from the trace
  5. M 3.7 4 km N of Magna, Utah
    2020-03-18 · 9 km from the trace
  6. M 3.6 4 km N of Magna, Utah
    2020-03-18 · 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.