The Kodiak cluster is named for Kodiak Island in the Aleutian Island
chain of Alaska. The distribution of seismograph stations in the region
requires that the cluster be rather large, geographically, and it is
necessary for robust location calibration to include earthquakes deep in
the subduction zone, to depths of ~160 km, which provides raypaths to
the northwest for good azimuthal coverage. The cluster contains many
events in the magnitude 5-6 range, but no events of magnitude 7 or
greater. Some events are only recorded to far regional distances. All
events have depth control, often from near-source and local-distance
arrivals as well as teleseismic depth phases, and in many cases,
waveform modeling.
