The Borah Peak, Idaho Earthquake of October 28, 1983—Landslides

Abstract

The Borah Peak, Idaho earthquake caused several hundred landslides throughout an area of about 4,200 km2. The most numerous landslides were rock falls and rock slides, which occurred where slopes contained conspicuous, through-going, open fractures or were composed of weakly cemented rocks. The earthquake also produced several slumps and cracks in man-made fill, several soil liquefaction phenomena, a large debris flow, a large mud flow, and a few ground failures of other types. The most significant landslide damage was in Challis, where rock falls damaged at least 3 houses and 2 automobiles.

Hydrology and hillslope processes explain spatial variation in tree‐ring responses to the 1983 earthquake at Borah Peak, Idaho, USA

“…The range is composed of highly deformed Paleozoic sedimentary and metamorphic rocks dissected by northwest‐trending normal faults, with Holocene alluvial and glacial outwash deposits filling the adjacent valleys (Taylor et al, ). The hydrology of the region is striking, including disappearing streams that feed into the Snake River Aquifer to the southeast, as well as numerous springs throughout the valleys (Keefer et al, ).…”

“…The quake involved up to 3 m of vertical displacement, primarily through dropping of the valley west of the Lost River Range, and up to 1 m of left‐lateral displacement (Taylor et al, ). It also produced numerous landslides and rockfalls over an area covering more than 4000 km 2 , and although it was centered on a sparsely populated valley, it caused two fatalities in the small Idaho town of Challis (Keefer et al, ). The potential for earthquakes to produce hydrologic changes is well established (Montgomery and Manga, ; Mohr et al, , ; Wang and Manga, ), particularly for large, normal fault quakes (Muir‐Wood and King, ), and effects of the Borah Peak quake on the region's unusual hydrology were expressed in liquefaction, slumps, debris flows, and sand boils (Keefer et al, ; Waag and Lane, ; Youd et al, ), as well as localized flooding and increases in well levels and the flow of springs and streams (Wood et al, ; Muir‐Wood and King, ).…”

“…It also produced numerous landslides and rockfalls over an area covering more than 4000 km 2 , and although it was centered on a sparsely populated valley, it caused two fatalities in the small Idaho town of Challis (Keefer et al, ). The potential for earthquakes to produce hydrologic changes is well established (Montgomery and Manga, ; Mohr et al, , ; Wang and Manga, ), particularly for large, normal fault quakes (Muir‐Wood and King, ), and effects of the Borah Peak quake on the region's unusual hydrology were expressed in liquefaction, slumps, debris flows, and sand boils (Keefer et al, ; Waag and Lane, ; Youd et al, ), as well as localized flooding and increases in well levels and the flow of springs and streams (Wood et al, ; Muir‐Wood and King, ). While most of these changes were temporary and took place between the growing seasons of 1983 and 1984, some wells remained high, and more persistent increases in spring or stream flow for other quakes have been noted (Muir‐Wood and King, ; Manga, ; Montgomery and Manga, ; Manga and Rowland, ).…”

“…Downstream‐tilted trees in the stream channel suggested some flooding that may have been associated with increased flows immediately after the quake (Wood et al, ; Manga, ; Montgomery and Manga, ). The Birch Springs site included perennial springs emanating from morainal deposits, and experienced a slow‐moving, complex slump and debris flow within 1–2 days following the quake, which extended approximately 200 m downslope from the crown and over the fault scarp (Keefer et al, ; Keefer, ). The Cedar Creek site encompassed a steep ravine carved by a perennial stream, and included an extensive landslide scarp and many tilted trees, including some with scars and rocks (most <0.5 m 3 ) at their base, suggesting rockfall events.…”

Landslides triggered by the 12 January 2010 Port-au-Prince, Haiti, &lt;i&gt;M&lt;/i&gt;&lt;sub&gt;w&lt;/sub&gt; = 7.0 earthquake: visual interpretation, inventory compiling, and spatial distribution statistical analysis

“…The earthquake caused widespread damage west of and in the capital city of Port-au-Prince, and killed more than 230 000 people (Bilham, 2010;Bellerive, 2010;Calais et al, 2010;Hough et al, 2010;Koehler and Mann, 2011). The earthquake also triggered extensive landslides, some of Carro et al (2003) Hyōgo-ken-Nanbu, Japan 17 January 1995 6.9 Points 674 700 Fukuoka et al (1997) Northridge, California 17 January 1994 6.7 Polygons 11 000 23.8 10 000 Jibson (1995, 1996); Jibson and Harp (1994) Loma Prieta, California 17 October 1989 6.9 Points 1046 2000 Keefer (2000) Ecuador 5 March 1987 7.0 2500 Tibaldi et al (1995) Borah Peak, Idaho 28 October 1983 6.9 Points Several hundreds 4200 Keefer et al (1985) Murchison, New Zealand 17 June 1929 7.7 Polygons > 7400 200 5000 Pearce and O'Loughlin (1985); Adams (1980) which caused damages such as blocked roads, dammed rivers and streams, and threatened infrastructures in many parts of Haiti (Eberhard et al, 2010;Stumpf and Kerle, 2011;Xu et al, 2012). Co-seismic landslide inventory compiling is essential for associated co-seismic landslides studies, and spatial distribution statistical analysis of those landslides is important in understanding which areas are most susceptible to landslides in future earthquakes.…”