Short-wave effects on mud deposition at a flat-marsh interface

PRATOLONGO, P.D.; PERILLO, G.M.E.; PICCOLO, M.C.

Amelia Island, Florida, USA

Conferencia; AGU Chapman Conference on Physics of Wave-Mud Interaction; 2008

American Geophysical Unino

Although the Bahia Blanca Estuary(Argentina) is, in general, in an erosionalstage, there are certain sectors in whichdepositional processes are occurring due tolocal hydrodynamic conditions. Forinstance, a number of Spartina marshes havedeveloped since the major dredging of the6D Ian navigational channel made in 19891990.The Villa del Mar tidal flat-marshcomplex is regularly affected by short,locally generated waves due to the strongwinds that commonly affect the estuary.Measurements of wave and tidal currentswere made at the interface between themarsh and tidal flat with two ADV, eachlocated every environment, for a neap-springtidal cycle. The ADV systems also allowedthe determination of the distance of thesensors to the sediment surface. Events ofmud deposition and posterior erosion weredetected after intensive wave activity,however, these depositions wereconcentrated only on the tidal flat and therewere only minor changes on the marsh. Infact, it is clear from the analysis of themarsh, inclusive from data of SET, thatsedimentation in this complex only occur atthe tidal flat , whereas few sectors of themarsh are actually having somesedimentation in mud pocketsdepositional processes are occurring due tolocal hydrodynamic conditions. Forinstance, a number of Spartina marshes havedeveloped since the major dredging of the60 krn navigational channel made in 19891990.The Villa del Mar tidal flat-marshcomplex is regularly affected by short,locally generated waves due to the strongwinds that commonly affect the estuary.Measurements of wave and tidal currentswere made at the interface between themarsh and tidal flat with two ADV, eachlocated every environment, for a neap-springtidal cycle . The ADV systems also allowedthe determination of the distance of thesensors to the sediment surface. Events ofmud deposition and posterior erosion weredetected after intensive wave activity,however, these depositions were concentrated only on the tidal flat and therewere only minor changes on the marsh. Infact, it is clear from the analysis of themarsh, inclusive from data of SET, thatsedimentation in this complex only occur atthe tidal flat , whereas few sectors of themarsh are actually having somesedimentation in mud pockets