The Oregon-Nevada lineament is a 750-km-long northwest-to north-northwest-trending belt of closely spaced, partly en echelon faults extending from central Oregon to central Nevada. The lineament is also marked by centers of volcanic activity that yielded voluminous late Miocene lava flows in Nevada and Miocene and younger volcanic rocks in Oregon. A conspicuous aeromagnetic anomaly is coextensive with the lineament in Nevada. The lineament is considered to be the surface expression of a deep-seated fracture zone that may have had a complex history of strike-slip and tensional movement.