A large strike-slip earthquake occurred in the Caribbean Sea on 28
January 2020. We inverted teleseismic P-waveforms from the earthquake to
construct a finite-fault model by a new method of inversion that
simultaneously resolves the spatiotemporal evolution of fault geometry
and slip. The model showed almost unilateral rupture propagation
westward from the epicenter along a 300 km section of the Oriente
transform fault with two episodes of rupture at speeds exceeding the
local shear-wave velocity. Our modeling indicated that the 2020
Caribbean earthquake rupture encountered a bend in the fault system
associated with a bathymetric feature near the source region. The
geometric complexity of the fault system triggered multiple rupture
episodes and a complex rupture evolution. Our analysis of the earthquake
revealed complexity of rupture process and fault geometry previously
unrecognized for an oceanic transform fault that was thought to be part
of a simple linear transform fault system.