- Basin and Range faults in Oregon are responsible for the rifting, or pulling apart, of a large block of southeast Oregon. These faults typically run along the base of a rising mountain range, bordering a sinking basin, and are moderately active with magnitude 5-6 earthquakes at intervals of many thousand years.
- The Brothers Fault is a wide zone made up of hundreds of small parallel faults across the relatively young volcanic rocks of the High Lava Plains. None are known to be active.
- The Cascadia Fault marks the edge of Oregon’s active subduction zone. It is very active, producing magnitude 8-9 earthquakes on average every 450 to 500 years, with the last event in 1700 AD.
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- The Corvallis Fault runs along the edge of the Siletzia exotic terrane, but show some evidence of activity within the last few hundreds of thousands of years.
- The Gales Creek and Portland Hills Faults run uncomfortably close to the Portland urban area and may have produced earthquakes in the magnitude 5-6 range over the last few thousand years.
- The John Day Fault runs the length of the upper John Day valley, and is responsible for the markedly straight course of the river valley. There is no evidence of activity on the fault for millions of years.
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