Spatial Variability and Robust Interpolation of Seafloor Sediment Properties Using the SEABED Databases

摘要

The US Geological Survey, in collaboration with Chris Jenkins of INSTAAR/Univ. Colorado, has recently released a large data base of seabed sedimentary properties in US coastal and shelfal waters. Dubbed 'usSEABED,' the data base is a compilation of available records of sedimentary data from seafloor samples, cores, and visual observations. This project is a collaborative effort with Jenkins. The long-term goals are to: (1) advance the understanding of the spatial variability of seabed properties as a function of geologic environment; (2) develop robust means of interpolation in the presence of uncertain data, (3) provide for the estimation of uncertainty in the interpolation at unsampled locations, and enable investigation of optimal survey design to minimize uncertainties; and (4) publish a computational/database structure capable of producing seafloor maps of wide geographic extent, for multidisciplinary use. As primary component of the study we examined the suitability of the aggregated usSEABED data collection for mapping and variability analysis. This project could provide a major advance in marine science, a set of reliable methods which transform point-site seabed data into griddings that will be useful across oceanographic disciplines, sediment transport, acoustics, habitat, wave-energy generation. Our work will result in a set of software tools that will be open source. These tools could be of importance to the Navy, particularly in dealing with areas with sparse data. In particular, an understanding of the relationship between environmental parameters, geologic setting and spatial variability could provide an ability to predict the amount and spatial scales of seabed variability using a parameterized semi-variogram model. This functionality provides a basis upon which to predict seabed parameters at unsampled locations, and to assess the uncertainty in that prediction.