A catastrophic #earthquake in 2010 on this fault system in #Haiti killed ~250k people. It just ruptured again, this time to the west. Hopefully the lower population density in this region, further from Port-au-Prince, will mitigate the impact. 😧
#tectoplot #haitiearthquake
#tectoplot #haitiearthquake
The updated focal mechanism for the earthquake from GFZ indicates the rupture was on land, and oblique thrust - similar to the overall 2010 event, which combines a mostly strike-slip mainshock with a cluster of smaller thrust earthquakes.
#tectoplot #haitiearthquake
#tectoplot #haitiearthquake
Scattered aftershocks from the 2010 earthquake were still occurring up through this year, although none were close in magnitude to the mainshock.
#haitiearthquake
#haitiearthquake
Why did this earthquake occur so close to the 2010 event? Well... the slip on the fault in 2010 stressed the regions next to it that didn't slip. So, this eq was probably triggered by the previous one, a fairly common scenario, although we don't really understand the time lags.
Both earthquakes occurred on the Enriquillo-Plantain Garden fault, which accommodates part of the ~19 mm/yr of left-lateral strike-slip between the North American and Caribbean plate....
...Here, the sliver plate is bounded by parallel (mostly) strike-slip faults; to the east, it becomes a complex doubly-vergent subduction zone with additional faults to take up obliquity.
• • •
Missing some Tweet in this thread? You can try to
force a refresh
