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Title: The Repeating Major Earthquakes in the Mexican Subduction Zone Along Oaxaca: Implications for Future Events
Abstract The subduction zone along Oaxaca, Mexico, has experienced multiple Mw ≥ 7 earthquakes that ruptured in close proximity several decades apart in at least three locations along the coast. Similarity of waveform recordings from a few long-period seismic stations at teleseismic distances has provided evidence for up to three repeated failures of the same slip patches, or persistent asperities, in the region. The evidence from prior single-station comparisons is bolstered by considering azimuthally distributed sets of body-wave recording pairs for the 1968 and 2018 Pinotepa Nacional (western Oaxaca), and 1965 and 2020 La Crucecita (eastern Oaxaca) earthquakes, as viewed in the long-period World-Wide Standardized Seismograph Network instrument passband (>5 s period). Drawing on detailed slip inversions for the most recent events and observations of their relationships with regional slow-slip events, we note features to be alert for in central Oaxaca where prior repeating events in 1928 and 1978 occurred and there is potential for a similar future event.  more » « less
Award ID(s):
1802364
PAR ID:
10611455
Author(s) / Creator(s):
; ;
Publisher / Repository:
Seismological Society of America
Date Published:
Journal Name:
Seismological Research Letters
Volume:
96
Issue:
3
ISSN:
0895-0695
Page Range / eLocation ID:
1548 to 1560
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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