QuakeIndex

Fault · Arizona

Pitaycachi fault

102 kmlong (63 mi), as mapped
< 0.2 mm/yrhow fast it slips
last 150 yearssince it last broke the surface
6quakes of M2.5+ within 10 km since 2016

In plain English

The two sides move less than 0.2 mm a year — under 2 cm a century. Slow faults can still produce large earthquakes, just rarely.

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

The largest earthquake recorded near it was M 7.6 in 1887 (The 1887 Sonora, Mexico Earthquake) — about 7,900,000 times the energy of an M3.0, the size people start to feel. It released about 3.8 megatons of TNT.

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

M 7.6 · 1887 · The 1887 Sonora, Mexico Earthquake
The Pitaycachi fault as mapped at the surface (glowing), with the other mapped faults nearby, 6 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 7.6 The 1887 Sonora, Mexico Earthquake
    May 3, 1887 · epicentre 5 km from the trace
  2. M 5.2 17 km W of Bavispe, Mexico
    July 31, 2021 · epicentre 4 km from the trace
  3. M 4.1 23 km NNE of Villa Hidalgo, Mexico
    August 18, 2021 · epicentre 2 km from the trace
  4. M 4.0 41 km ESE of Agua Prieta, Mexico
    August 16, 2026 · epicentre 4 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 4.0 41 km ESE of Agua Prieta, Mexico
    2026-08-16 · 4 km from the trace
  2. M 4.1 23 km NNE of Villa Hidalgo, Mexico
    2021-08-18 · 2 km from the trace
  3. M 3.1 19 km WNW of Huachinera, Mexico
    2021-08-10 · 8 km from the trace
  4. M 2.5 30 km WNW of Bavispe, Mexico
    2021-08-01 · 7 km from the trace
  5. M 5.2 17 km W of Bavispe, Mexico
    2021-07-31 · 4 km from the trace
  6. M 3.4 32 km E of Esqueda, Mexico
    2018-02-27 · 5 km from the trace

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.