Ages of Prehistoric Earthquakes Revealed by Cosmogenic Chlorine-36 in a Bedrock Fault Scarp at Hebgen Lake

Abstract

Cosmogenic chlorine-36 reveals dates of the multiple prehistoric earthquakes that have produced a scarp on the Hebgen Lake fault. Apparent chlorine-36 ages are stratigraphically correct, follow a predicted theoretical pattern, and produce geologically reasonable model ages of 24, 20, 7.0, 2.6, 1.7, and 0.4 thousand years ago. This result demonstrates the feasibility of using cosmogenic chlorine-36 to extract paleoearthquake records from bedrock fault scarps.

Palaeoearthquake histories across a normal fault system in the southwest Taranaki Peninsula, New Zealand

“…Similar variability of recurrence intervals has been observed in numerous natural fault systems globally (e.g. Sieh et al 1989;Marco et al 1996;Xu & Deng 1996;Zreda & Noller 1998;Weldon et al 2004;Mouslopoulou et al 2009) and are generally attributed to interactions between faults (e.g. Nicol et al 2006Nicol et al , 2009Dolan et al 2007;Mouslopoulou et al 2009).…”

The unusual temporal and spatial slip history of the Wassuk Range normal fault, western Nevada (USA): Implications for seismic hazard and Walker Lane deformation

“…If true, the slip-predictable Reid-type behavior of the Wassuk fault is unusual relative to other major fault systems worldwide. Wallace-type behavior has been documented on segments of the San Andreas fault system (Sieh et al, 1989;Grant and Sieh, 1994), faults associated with the East California shear zone (Rockwell et al, 2000), the Wasatch fault (e.g., McCalpin and Nishenko, 1996;Friedrich et al, 2003), the Dead Sea graben (Marco et al, 1996), the Oued Fodda fault in Algeria (Swan 1988), and the Hebgen Lake fault in Montana (Zreda and Noller, 1998). In these cases, it appears that the temporal nature of the clusters themselves varies significantly.…”

Displacement history of a limestone normal fault scarp, northern Israel, from cosmogenic36Cl

“…This and other studies [Noller et al, 1996;Zreda and Noller, 1998] Provided that exposure histories are simple and scarps are in good condition, cosmogenic dating will determine scarp ages more precisely and more accurately than measuring relative weathering characteristics. Nuclide measurement can constrain the timing of displacement, even when geomorphic clues, such as distinct weathering horizons, are absent.…”

“…Cosmogenic dating of fault scarp surfaces is a viable and potentially powerful new method for determining paleoseismic histories of bedrock scarps [Noller et al, 1996;Zreda and Noller, 1998]. The increasing precision of cosmogenic isotope measurements and continued refinement of 36C1 depth-production models [Liu et For in situ cosmogenic nuclides to provide paleoseismic information on a bedrock scarp, the scarp must be exposed by faulting rather than other processes, such as differential erosion of the hanging wall.…”