QuakeIndex

Fault · Oregon

Blanco transform fault

102 kmlong (63 mi), as mapped
> 5 mm/yrhow fast it slips
< 15,000 yearssince it last broke the surface
20quakes 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.

Its most recent surface rupture is younger than 15,000 years.

The largest earthquake recorded near it was M 6.0 in 1945 (136 km WSW of Pistol River, Oregon) — about 32,000 times the energy of an M3.0, the size people start to feel. It released about 15 kilotons 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

Cascadia megathrustCascadia fold and fault beltThompson Ridge fault M 6.0 · 1945 · 136 km WSW of Pistol River, Oregon
The Blanco transform fault as mapped at the surface (glowing), with the other mapped faults nearby, 20 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 6.0 136 km WSW of Pistol River, Oregon
    September 28, 1945 · epicentre 6 km from the trace
  2. M 4.9 125 km WSW of Port Orford, Oregon
    August 6, 2026 · epicentre 4 km from the trace
  3. M 4.1 116 km W of Gold Beach, Oregon
    August 8, 2026 · epicentre 6 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 4.1 116 km W of Gold Beach, Oregon
    2026-08-08 · 6 km from the trace
  2. M 4.9 125 km WSW of Port Orford, Oregon
    2026-08-06 · 4 km from the trace
  3. M 2.7 137 km W of Gold Beach, Oregon
    2026-06-12 · 9 km from the trace
  4. M 2.5 132 km WSW of Port Orford, Oregon
    2026-05-05 · 6 km from the trace
  5. M 2.7 124 km WSW of Port Orford, Oregon
    2025-09-12 · 3 km from the trace
  6. M 2.7 119 km W of Pistol River, Oregon
    2025-03-30 · 4 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.