A global prediction of seafloor sediment porosity using machine learning

Abstract

AbstractPorosity (void ratio) is a critical parameter in models of acoustic propagation, bearing strength, and many other seafloor phenomena. However, like many seafloor phenomena, direct measurements are expensive and sparse. We show here how porosity everywhere at the seafloor can be estimated using a machine learning technique (specifically, Random Forests). Such techniques use sparsely acquired direct samples and dense grids of other parameters to produce a statistically optimal estimate where direct measurements are lacking. Our porosity estimate is both qualitatively more consistent with geologic principles than the results produced by interpolation and quantitatively more accurate than results produced by interpolation or regression methods. We present here a seafloor porosity estimate on a 5 arc min, pixel registered grid, produced using widely available, densely sampled grids of other seafloor properties. These techniques represent the only practical means of estimating seafloor properties in inaccessible regions of the seafloor (e.g., the Arctic).