Characterizing an "uncharacteristics" ETS event in northern Cascadia

K. Wang; H. Dragert; H. Kao; E. Roeloffs

doi:10.1029/2008gl034415

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Characterizing an "uncharacteristics" ETS event in northern Cascadia

K. Wang·H. Dragert·H. Kao·E. Roeloffs

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Abstract

GPS and borehole strainmeter data allowed the detection and model characterization of a slow slip event in northern Cascadia in November 2006 accompanying a brief episode of seismic tremor. The event is much smaller in area and duration than other well-known ETS events in northern Cascadia but is strikingly similar to typical ETS events at the Nankai subduction zone. The 30-45 km depth range and the 2-3 cm slip magnitude as interpreted for this event appear to be common to most ETS events in these two subduction zones, regardless of their sizes. We infer that the Nankai-type small ETS events must be abundant at Cascadia and that ETS event at the two subduction zones are governed by a similar physical process. Copyright 2008 by the American Geophysical Union.

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K. Wang, H. Dragert, H. Kao, E. Roeloffs. 2008-08-06. Characterizing an "uncharacteristics" ETS event in northern Cascadia. https://doi.org/10.1029/2008gl034415

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