modeling short-term hydrosedimentary processes and the preservation of river dune deposits suzanne...
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Modeling short-term hydrosedimentary processes and the preservation of river dune deposits
Suzanne LeclairMontréal, QC, CANADA
Theory Experiment
Modeled distributions of dune height and trough elevation based on observed dune migrating behaviour
(without sediment vertical sorting—and hence no constraint on dune scouring)
From Leclair , Sedimentology 2002)
Observations Results vs Simulation model
From Leclair, 2006, GEOLOGY
Inverse modeling:Interpretation of sedimentary record
-15
-10
-5
0
5
10
15
20
25
0 10000 20000 30000 40000
Distance (m)
Ele
vati
on
rel
ativ
e to
dat
um
(m
)Modeling the thickness of
preserved deposit from various hydrographical events at the
channel scale
Observed alongstream dune-bed elevations in the Mississippi River
Quaternary Loire
?
(Research program while at Tulane University– supported by the Board of Regents of Louisiana)
18 m
5 km
Predicting mean thickness of channel deposit --or erosion
bed elevation below 0, m02468
Fra
ctio
n o
f d
istr
ibu
tion
0.5
0.6
0.7
0.8
0.9
1.01st peak rising
2nd peak
falling
3.1 m
(1.3m)
1.5 m1 m(0.8 m)(0.9 m)
Preserved after 1 year
?