HEY WHERE DID THAT COME FROM? - A COMBINED GEOCHEMCIAL AND GEOPHYSICAL APPROACH TO SEDIMENT TRANSPORT DYNAMICS
We present a coupled geophysical and geochemical approach to tracing the movement of material through areas of ephemeral, metastable and stable accretion and erosion. This approach assesses the spatial and temporal aspects of sediment transport and provides insight into where certain geochemical species originated, how long they have been in the system and their ultimate fate. Our approach uses high-resolution geophysics to aerially and volumetrically map source and sink areas with an initial survey. Concurrent with this survey, surficial sediment samples and/or sediment cores are collected to geochemically characterize and construct inventories of source and sink areas and provide detailed geochronologies. Repeated surveys and sampling integrate temporal and spatial aspects in a sediment budget and sediment/geochemical transport model that are related to specific events within the basin.
Initial data collected from sites within Boston Harbor will be shown to illustrate the initial geophysical surveying and geochemical inventory construction phases of the integrated approach.