Assessing the influence of climate on Antarctic submarine gully evolution  

Abstract

Antarctica’s continental slopes hold invaluable insights for understanding past climate, ice-sheet dynamics, ocean circulation, erosional and depositional processes, and submarine geohazards over millennial timescales. We present a multidisciplinary dataset from the Ross Sea continental margin, Antarctica from the EUROFLEETS-funded ANTSSS expedition and International Ocean Discovery Program Expedition 374, including core records spanning ~3 Ma, multibeam echosounder and single-channel seismic data and legacy seismic data available through the Antarctic Seismic Data Library System. Here, gully and channel systems occur at the head of the Hillary Canyon, with palaeo-gullies evident in seismic data. New sediment core-seismic correlations show that palaeo-gullies evolved on the Ross Sea continental margin over multiple glacial cycles, filling and reforming associated with glacial advances, cold dense water cascading and other processes. We show multidisciplinary datasets that constrain the signature of down and along-slope processes and examine factors driving their timing, frequency, and impact on gully evolution. We discuss the implications of these findings in relation to Neogene and Quaternary West Antarctic Ice Sheet expansions to the shelf edge.