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The effect of sediment transport mechanism on depositional behaviour
within river delta environments
H. van der Vegt1, J.E.A. Storms1, D. J. R. Walstra1,2, N. C. Howes3, L. Li1
This work was carried out on the Dutch national e-infrastructure with the support of
SURF Foundation
1 Delft University of Technology
2 Deltares
3 Shell Research and Technology
2
Sediment Transport
Bed load : Suspended load
Influence
3
Sediment Transport
Bed load : Suspended load
Influence
Delta stratigraphy and morphology
4
Delta depositional patters • Morphology
• Stratigraphy
Orton and Reading 1993
5
Sediment Supply
Composition • Cohesivity
• Grain size
distribution
Hydrodynamics • Fluvial input
• Tidal conditions
• Wave Activity
Delta depositional patters • Morphology
• Stratigraphy
Orton and Reading 1993
6
Sediment Supply
Composition • Cohesivity
• Grain size
distribution
Hydrodynamics • Fluvial input
• Tidal conditions
• Wave Activity
Delta depositional patters • Morphology
• Stratigraphy
Orton and Reading 1993
7
Delta depositional patters • Morphology
• Stratigraphy
Ge
leyn
se
et.
al 2
011
Sediment Supply
Composition • Cohesivity
• Grain size
distribution
Hydrodynamics • Fluvial input
• Tidal conditions
• Wave Activity
8
Sediment Transport
Delta depositional patters • Morphology
• Stratigraphy
Sediment Supply
Composition • Cohesivity
• Grain size
distribution
Hydrodynamics • Fluvial input
• Tidal conditions
• Wave Activity
9 Q
Cohesiv
e
ma
teria
l
(Silt
, C
lay)
Non
-cohe
siv
e
ma
teria
l
(Sa
nd
, g
rave
l)
Su
sp
en
de
d lo
ad
B
ed
lo
ad
Sediment
Transport Cohesivity
10 Q
Co
he
siv
e
ma
teria
l
(Silt
, C
lay)
No
n-c
oh
esiv
e
ma
teria
l
(Sa
nd
, g
rave
l)
Su
sp
en
de
d lo
ad
B
ed
lo
ad
Field and experimental
measurements available
Measurement difficult and rare.
Values usually approximated
Sediment
Transport Cohesivity
11
5 km
5 k
m
1.1 1.2 1.3
2.1 2.2 2.3 2.4
3.1 3.2 3.3 3.4
4.1 4.2 4.3 4.4
Increase bed load In
cre
ase
no
n-c
oh
esiv
e s
up
ply
12
Sediment Transport
Bed load : Suspended load
Influence
Delta stratigraphy and morphology
13
Similar channel dynamics in non-cohesive and bed-load driven systems
1. Deltaic sediment body can originate from a
non-unique sequence of depositional controls
and events.
14
1.1 1.2 1.3
2.1 2.2 2.3 2.4
3.1 3.2 3.3 3.4
4.1 4.2 4.3 4.4
74% 73% 64%
76% 68% 62% 61%
59% 61% 65% 72%
73% 62% 61% 57%
Mean channel depth:
2.41m 2.78m 1.69m
2.99m 2.00m 1.59m 1.4m
2.02m 1.54m 1.44m 1.37m
1.02m 0.64m 0.56m 0.51m
Increase bed load In
cre
ase
no
n-c
oh
esiv
e s
up
ply
15
5 km
5 k
m
1.1 1.2 1.3
2.1 2.2 2.3 2.4
3.1 3.2 3.3 3.4
4.1 4.2 4.3 4.4
Increase bed load In
cre
ase
no
n-c
oh
esiv
e s
up
ply
16
Sediment Transport
Bed load : Suspended load
Influence
Delta stratigraphy and morphology
17
2. Channel kinematics control proximal, but
not distal deposition
18
19
3. Allogenic vs. Autogenic control
(Panther Tongue from A. Forzoni et. al., 2015)
20
(Muto et. Al. 2007)
(Panther Tongue from A. Forzoni et. al., 2015)
Large scale autogenic: Risk misinterpretation allogenic
21
5 km
5 k
m
1.1 1.2 1.3
2.1 2.2 2.3 2.4
3.1 3.2 3.3 3.4
4.1 4.2 4.3 4.4
Increase bed load In
cre
ase
no
n-c
oh
esiv
e s
up
ply
22
23
Large scale autogenic: Risk misinterpretation allogenic
Increased risk: suspended load or cohesive
systems
(Panther Tongue from A. Forzoni et. al., 2015)
24
Sediment Transport
Bed load : Suspended load
Influence
1. Deltaic sediment body can originate from a non-
unique sequence of depositional controls and
events.
2. Channel kinematics control proximal, but not
distal deposition
3. Autogenic misinterpretation as allogenic larger
risk in suspended load and cohesive systems
25
Helena van der Vegt
TU Delft / Civil Engineering and Geosciences
Department of Geoscience and Engineering
E h.vandervegt@tudelft.nl
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