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Morey et al., 2013, describe disturbance event sequences from southern Cascadia lakes, and compare event timing and frequency to the marine record of Cascadia earthquakes. The locations of the sedimentary sequences used in this study are shown in Figure 1 (shown to the right). Three of the lakes, Bolan, Sanger and Upper Squaw Lakes, are located in the Klamath Mountains near the California/Oregon border.

Fig 1. Lake and marine core locations used in this study. Modified from Fig. 1 of Morey et al., 2013.

Fig 1. Lake and marine core locations used in this study. Modified from Fig. 1 of Morey et al., 2013.

 

Conclusions

“The similarities between downcore magnetic susceptibility and associated radiocarbon data from both lake and marine cores over great distances and multiple depositional environments supports synchroneity and therefore earthquake triggering. Lithologic characteristics of the disturbance event deposits suggest instantaneous deposition, and include many of the features of turbidites found in the marine record with some differences based on sediment supply and setting. The presence of earthquake-triggered deposits in forearc lakes may provide important information useful for hazard assessment from the coast inland to more populated areas. In addition, the analysis of these deposits from lakes throughout Cascadia may provide insight as to subduction zone characteristics, such as rupture lengths and segmentation.”

See link below for a summary of this work in poster form (Morey et al., 2011; American Geophysical Union poster presentation):