Submarine canyons are prime conduits for sediment-laden flows that link terrestrial sediment sources with deep-marine depocenters. If the distance between the canyon head and the shore is short, terrestrial sediment, associated pollutants and organic carbon is efficiently delivered to the deep ocean. The efficiency of sediment routing from land to the ocean depends on the position of submarine canyon heads with regard to terrestrial sediment sources. However, the detailed controls on why a submarine canyon is incised into the shelf or why it remained connected or became disconnected from terrestrial sediment supply during rising sea level are poorly understood.
In this dataset, we identified 4717 canyon heads a long the major continents between 50°N and 50°S (excluding islands). We assigned 55 variables to these submarine canyon heads, including terrestrial and marine topographic variables, oceanographic variables, lithologic variables of the onshore catchments, and canyon topographic variables. These data can be used to better understand the geomorphology and extent of submarine canyons and their connectivity to terrestrial sediment sources.
Man-made pollution of the environment is mainly due to inputs of pollutants and their transport in the geosphere, to storage and transformation by biological and chemical processes. The evaluation, prevention and clean up of pollution needs a thorough understanding of the concerned natural processes. The study of biogeochemical cycles in the environment is therefore one of the main topics of natural sciences in environmental research. The Swiss National Foundation for Scientific research started at the beginning of 1994 a new coordinated research program on biogeochemical cycles. The main goal of this Module 2 of the Priority Program Environment is the creation of a Swiss multidisciplinary network in the field of biogeochemical cycles, allowing as many research groups as possible to participate. The purpose of this common program is to investigate qualitatively and quantitatively the role of carriers on the fluxes of vital and detrimental compounds inside compartments and at the compartment boundaries: air, soil, sediments, surface water, subsurface and ground water. During 1994-1995, research will be focused in particular on sub micron colloids which are very little known. Leading Questions: What are the macroscopic processes of contaminant transport in complex natural environments (system analysis)? Occurence and properties of colloidal carriers in the air, the soil and the water? Mobility of colloidal carriers of contaminants? Implications for the contaminant transport (sorption, desorption, transformation)? Methods of sampling, preparation, analysis?