Decoding tectonic and lithological controls on sediment exported from footwall catchments: Implications for hanging-wall stratigraphy

Abstract Hillslope and river channel processes combine to erode topography and release sediments in response to external forcing, such as tectonics. Any forcing that drives these processes to shape topography likely also controls the resulting sediment characteristics; however, the extent to which the forcing translates into exported sediment grain size remains elusive, especially where tectonic and lithological forcings coexist. Here, we focus on two catchments with these characteristics in the Gulf of Corinth, Greece, to probe how tectonics and lithology compete to control exported sediment grain size via hillslope and channel processes. Topographic analysis reveals that both tectonic and lithological forcings can drive hillslope and channel processes to shape topography. In the Sithas catchment, normal faulting older than 600 ka initiates knickpoints that steepen hillslopes and trigger concentrated mass-wasting downstream of the knickpoints. In the Phoenix catchment, which was only perturbed by active faulting for