Sediment Budgets Flashcards
oil spilled on a coastline gets deposited on a beach, since the oil is heavier than the sand, it gets burried
deadmans island
the skull came from a cemetery, they didnt know there was a cemetery, the sand eroded and exposed the cemetery
sand being eroded from glacial period dunes, sand moves along the shoreline (littoral driftlines - shows the direction sand moves along the shoreline)
bridge and marina entrance blocks the source of material to deadmans island area. area started eroding super rapidly
source and sink
bluffs in lake erie are the source, drift lines point from source to sink, longpoint is the sink
longpoint is eroding
sediment budget
where the excess and deficits of sands are
source of sediments
sink for sediment
drift from source to sink
sediment movement is episodic, but over the long term it goes from source to sink
conservation of mass
input vs output
the gradient (the difference)
x is cross-shore, y is alongshore
shoreline change
h is the depth of closure at which there is no more change
volume is length along the shoreline times amount changed in the cross-shore times the depth
change in volume is volume in versus out over time
the amount of erosion/deposition = how much sand came in - how much came out * over what time / length of beach * depth of beach
change over time = sand in - sand out / length of beach * depth
barrier breaching
breaking of the barrier
-point pelee has been constantly breaching for the last hundred years
-episodic
-> breaching at high water levels, correcting at low water levels
breach started to heal itself even though water levels are high
-high water levels make supply
-erosion means deposition, we just dont know where
Hillman Marsh
-breach formed, no recovery because of rock walls, breach stays open
source: river
moving sand down the coast
sink: mangroves
force deposition, mangroves continue to grow and grow
