Surface faulting accompanying the Borah Peak earthquake, central Idaho

The December 1872 Washington State Earthquake

“…The earthquake caused a 36-km-long northwest-trending zone of surface faulting near the southwest edge of the Lost River Range (Crone et al, 1987). Aftershocks in the 24 hours after the mainshock occurred southwest of the surface rupture all along the surface rupture (Richins et al, 1987).…”

National Earthquake Hazards Reduction Program, summaries of technical reports, volume XXVII

“…Soil development on fans and terraces both younger and older than 15 ka should help constrain the timing of recent faulting and rates of long term relative uplift Displacement along the range-front fault will be discussed first followed by comments on rupture within bedrock. Vertical displacement from the 1983 earthquake is maximum near the center of the Thousand Springs fault segment and tapers, toward the south, to a low value at Elkhorn Creek (Crone andMachette, 1984, andCrone andothers, 1985). A similar pattern was documented for cumulative, post-glacial, vertical displacement Cumulative displacement for the two events is maximum (about 4.5 m) near the center of the segment and tapers to lower values toward Elkhorn Creek, suggesting the events were nearly identical in magnitude and spatial position along the fault This confirms a comment of Schwartz and Crone (1985) and conforms to implications of the characteristic earthquake model of fault behavior (Schwartz and Coppersmith, 1984).…”

United States earthquakes, 1983

“…29). The 34-km-long discontinuous surface faulting had a throw that ranged from 50 em to 2.7 m and ground breakage over a width of as much as 100 m (Crone and Machette, 1984). The most severe damage occurred at Mackay and Challis, Idaho, where a report by the Governor's office listed a total of 11 businesses and 39 homes sustained major damage and 200 homes suffered minor to moderate damage.…”

“…IdahoFresh fault scarps and surface ruptures extended northwesterly over a distance of about 34 km, mostly along the surface trace of the Lost River fault (Crone and Machette, 1984). Crone and Machette (1984) reported "The most extensive breakage is along the 8-kmlong zone between West Spring and Cedar Creek" (located IDAHO--Continued north and south of Doublesprings Pass Road).…”

“…Crone and Machette (1984) reported "The most extensive breakage is along the 8-kmlong zone between West Spring and Cedar Creek" (located IDAHO--Continued north and south of Doublesprings Pass Road). The violent shaking, combined with differential movement on individual faults along this zone, shattered the ground surface into randomly tilted blocks several meters in width.…”