Hyperpycnal flow behavior generated by physical simulations: a comparison between confined and unconfined flows.

Abstract

The study of hyperpycnal flows (a type of sediment gravity flow) is extremely important in the petroleum industry, since deposits generated by such flows become potential hydrocarbon reservoirs. In order to understand these sedimentary processes in marine environment, laboratory experiments (physical modeling) with controlled input parameters are being performed more accurately to reproduce this natural complex phenomenon. Using this power tool, this work aims to compare the behavior of a hyperpycnal flow in two different situations, i.e., confined and unconfined flow in a subaqueous channel. We sought to establish the hydrodynamic differences and their implications in the transport and deposition of sediments during a short instant of time from a tridimensional physical experiment of long duration. Through the analysis of images was possible to establish correlations of velocity, acceleration and geometry between the two flow situations. The results show that the hyperpycnal flow generated at the beginning of the experiment accelerates both temporally and spatially as well as modifies its geometrical characteristics (elongation of the frontal region). In natural environments, such a locally and short phenomenon can occur through large distance and duration, this can afford an increase in flow velocity through the way, providing a greater occurrence of erosive process compared with depositional processes.