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Focal mechanisms and magnitude distributions of “off-fault” earthquakes. David D. Jackson, Yan Kagan, and Qi Wang, UCLA Stefan Hiemer , ETH Zurich. Focal mechanisms. At each point, assumed moment tensor is weighted sum of those for nearby earthquakes and fault elements
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Focal mechanisms and magnitude distributions of “off-fault” earthquakes David D. Jackson, Yan Kagan, and Qi Wang, UCLA Stefan Hiemer, ETH Zurich
Focal mechanisms • At each point, assumed moment tensor is weighted sum of those for nearby earthquakes and fault elements • Weighting inversely proportional to distance • For moment tensors on faults, weighting proportional to moment rate on fault element.
Focal mechanisms derived from earthquakes and faults, respectively
Optimization of seismicity/fault weighting and smoothing distance
Magnitude distribution for all quakes, and quakes on faultsExpected size limit depends on time window.