Author(s): Richard I. Wilson; Heide Friedrich; Craig Stevens
Linked Author(s): Heide Friedrich
Keywords: No Keywords
Abstract: The turbulent propagation and sediment deposition of turbidity currents is known to cause degradation to benthic flora and fauna with key physical aspects being the depth and resilience of the sediment deposited. Often induced by earthquakes causing submarine landslides–such as the November 2016 Kaikōura, New Zealand earthquake–they also pose a risk to submarine structures, including pipelines and submarine cables. In laboratory models, it has become popular to use quantitative photometric techniques to measure turbidity current flow characteristics. This is driven by the low cost and non-intrusive nature of the technique. However, existing quantitative techniques are not readily suitable for unconfined experimental turbidity currents that are visually obstructed by obstacles and conventional measurement techniques. In the present study, we develop a spatial calibration and thresholding technique to allow the spatial propagation of an obstructed, unconfined turbidity current to be quantified. Testing currents over a range of initial densities and substrate conditions, we then apply the technique to investigate the flow characteristics of the current, providing insights into how obstacles affect current entrainment mechanisms and lateral propagation.