Advancements in Understanding Deep-Sea Clastic Sedimentation Processes: a preface

The aim of this Special Issue is to focus on current research on processes that lead to widespread clastic sedimentary deposits in the deep sea. Most of our knowledge of the ocean lies in shallower waters, whereas deep waters largely remain a mystery. Yet there is increasing reliance on these areas for food, energy and minerals amongst other resources. The deep sea is increasingly targeted by exploration for economic resources (especially hydrocarbons and precious metals) and for infrastructure installations (e.g. pipelines, telecommunication cables, production platforms). It is also the ultimate sink for elements such as carbon that associate with sediments, so it is important to understand residence and recycling times that these processes entail. Terrigenous sediment makes up more than 80% of the sediment volume in the ocean basins and an even higher proportion in marginal seas. Pelagic sediment covers more than 80% of the surface of the deep-ocean floor and is thus highly significant for chemical mass-balances and paleoceanographic studies. On continental margins, where great thicknesses of terrigenous sediment have accumulated, pelagic sediment is rare.