Sediment Deposition from Turbidity Currents

The flow dynamics of an extremely large volume pyroclastic flow, the 2.08-Ma Cerro Galán Ignimbrite, NW Argentina, and comparison with other flow types

“…In comparison, the deposits of short-lived highly expanded, fully turbulent, subaqueous sedimentary turbidity currents are usually normal size-graded, unless they result from high particle concentration flows (Middleton 1993) or from sustained currents (e.g. Kneller and Branney 1995).…”

Turbidity Currents: Comparing Theory and Observation in the Lab

“…An alternative approach models the flow using a modified version of the Chézy Equation for steady uniform flow (see Middleton, 1993;Kneller and Buckee, 2000, for further details):…”

“…Turbidity currents form one class of sediment gravity flows (e.g., Middleton, 1993). They are an important mechanism of sediment transport in fluid environments (lakes and the ocean) as they move coarse-grained material from the margins to the interiors of basins.…”

“…Considerable theoretical work has evaluated the factors that contribute to flow velocity (e.g., Middleton, 1993;Meiburg and Kneller, 2009;. As the mass of sediment suspended in the flow increases, so does the density of the turbid flow relative to that of the ambient low-density water above it, and thus its velocity increases.…”

“…Studies suggest that appropriate Froude numbers for turbidity currents range between F r = 2 -1/2 to 1 for turbulent flow in deep water, while flows in finite water depth follow a relationship in which F r h/H, where h is the height of the turbulent flow, and H is the water depth (e.g., Middleton, 1993;Meiburg and Kneller, 2009). In addition to the Froude number, the properties of turbidity currents can be described using three additional dimensionless numbers, the Reynolds number, the Rouse number, and the Richardson number.…”