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Incoming links: W. Ellsworth
F. Waldhauser Created 2026-10-20 Updated 2026-11-05
F. Waldhauser co-developed double-difference earthquake relocation with W. Ellsworth. The method combines ordinary arrival-time data with precise waveform-based differential measurements, then adjusts relative source positions to fit those differences.[ref]
A Double-difference Earthquake Location Algorithm: Method and Application to the Northern Hayward Fault, California by F. Waldhauser and W. Ellsworth. Abstract: combined catalogue/cross-correlation observations and iterative solution
Closely related waveforms provide useful timing information through cross-correlation. Combining those observations with a network of stations can reveal structure within a seismic cluster that a collection of independently located events would blur.
W. Ellsworth Created 2026-10-20 Updated 2026-11-05
W. Ellsworth co-developed a double-difference earthquake relocation method with F. Waldhauser. Their algorithm compares differences in arrival times from nearby earthquakes recorded at common stations, reducing errors shared along similar propagation paths.[ref]
The result is improved relative location within an earthquake cluster, rather than an automatic exact absolute position. The distinction helps interpret fine fault geometry without confusing relative precision with the accuracy of the underlying velocity model.