Interseismic velocity field and coupling along the Ecuador Subduction interface in relation to the 2016 Pedernales Earthquake

On April 16, 2016, a magnitude 7.8 earthquake occurred along the Nazca-South America plate interface near the city of Pedernales, Ecuador. GPS measurements in the years prior to the earthquake had indeed shown a spatially heterogeneous pattern of partial to strong interseismic coupling in central-northern Ecuador (Nocquet et al., 2014, Chlieh et al., 2014). Here, we revisit these models using an updated velocity field including data of mostly continuous GPS stations. We identify several models whose results correspond to our observed data and we discuss their correlation with the slip distribution for the 2016 Mw 7.8 Pedernales earthquake. Additionally, we investigate if precursory signals were recorded in the GPS time-series prior to the 2016 event. Indeed, the precursory signal appears to be quite small and we will create a methodology to identify the small signals. Finally, we present a slip budget for the Ecuadorian subduction margin for the last 110 years, since the 1906 Mw 8.8 great earthquake, and discuss its implication for the observed segmentation patterns and seismic hazards along the north Ecuadorian subduction zone.