2017 Valparaíso earthquake sequence and the megathrust patchwork of central Chile
In April 2017, a sequence of earthquakes offshore Valparaíso, Chile, raised concerns of a potential megathrust earthquake in the near future. The largest event in the 2017 sequence was a M6.9 on 24 April, seemingly colocated with the last great-sized earthquake in the region—a M8.0 in March 1985. The history of large earthquakes in this region shows significant variation in rupture size and extent, typically highlighted by a juxtaposition of large ruptures interspersed with smaller magnitude sequences. We show that the 2017 sequence ruptured an area between the two main slip patches during the 1985 earthquake, rerupturing a patch that had previously slipped during the October 1973 M6.5 earthquake sequence. A significant gap in historic ruptures exists directly to the south of the 2017 sequence, with large enough moment deficit to host a great-sized earthquake in the near future, if it is locked.
Citation Information
Publication Year | 2017 |
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Title | 2017 Valparaíso earthquake sequence and the megathrust patchwork of central Chile |
DOI | 10.1002/2017GL074767 |
Authors | Jennifer Nealy, Matthew W. Herman, Ginevra Moore, Gavin P. Hayes, Harley M. Benz, Eric A. Bergman, Sergio E Barrientos |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Geophysical Research Letters |
Index ID | 70191860 |
Record Source | USGS Publications Warehouse |
USGS Organization | Geologic Hazards Science Center |