When large earthquakes strike mountainous regions, they often trigger widespread landslides that threaten communities, damage infrastructure, and disrupt water and sediment systems. These cascading hazards have far-reaching consequences, influencing river systems, water quality, and carbon transport. Understanding earthquake-induced landslides is therefore important not only for reducing disaster risks abroad, but also for improving hazard assessment and infrastructure resilience in the United States, where similar processes occur in regions such as Alaska, California, and the Pacific Northwest. However, major uncertainties remain in how frequently earthquakes generate landslides and how much carbon they mobilize. This project will address these gaps using the Himalayan Mountains as a natural laboratory. This research will quantify the role of earthquake-induced landslides in erosion and carbon mobilization. It will (1) develop landslide inventories and models to estimate long-term seismic landslide fluxes, (2) measure field samples to quantify organic carbon mobilized by landslides, and (3) use geochemical analyses to determine the reactivity and fate of mobilized carbon. Results will advance understanding of interactions among tectonics, surface processes, and the carbon cycle. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.