The world's second-largest, recorded landslide event: Lessons learnt from the landslides triggered during and after the 2018 Mw 7.5 Papua New Guinea earthquake

Events characterized by widespread landslides provide rare but valuable opportunities to investigate the spatial and size distributions of in relation seismic, climatic, geological morphological factors. This study presents a unique event inventory for co-seismic induced February 25, 2018 Mw 7.5 Papua New Guinea earthquake. The mainshock rupture was dominated reverse fault motion, this also case aftershocks. latter triggered combination with rainfall during period between 26 March 19. We mapped approximately 11,600 which, more than 10,000 were mainshock, total failed planimetric area about 145 km2. Such large makes world's second-largest recorded landslide after 2008 7.9 Wenchuan earthquake, where motion changed from predominantly thrust strike-slip. Large are abundant throughout located within remote Highlands. Specifically, half population is larger 50,000 m2 overall, post-seismic even their counterparts. To understand factors controlling distribution landslides' occurrence size, we combine descriptive statistics as well rigorous bivariate multivariate analyses. statistically show that 15-day antecedent precipitation plays role explaining landslides. Also, examine four strong aftershocks (Mw ? 6.0) 9 days demonstrate cumulative effect main factor disturbing steep hillslopes causing initiation very landslides, up ~5 Overall, dataset findings presented paper represent step towards holistic understanding seismic hazard assessment entire mainland.