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Fluvial response to climate over geological timescales Aart-Peter van den Berg van Saparoea George Postma

Fluvial response to climate and climate pulses over geological time scales

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Fluvial response to climateover geological timescales

Aart-Peter van den Berg van Saparoea

George Postma

Reconstruction of external forcing mechanisms of fluvial and deltaic deposits

Sea-level changeorclimate pulse?

Simplified fluvial systemClimate

Eustasy

Shelf and basin

Model setup

Experiments

DEM

Scan (photogrammetryor laser)

model

3 m

Synthetic stratigraphy

software

Neither!

Sea-level fluctuation in different stable climates

Sea-level changeorclimate pulse?

0 5 10 15 20 25 30

Time

Shelf and fluvial style in a stable climate

river shelf

basin

Low water discharge

0 5 10 15 20 25 30

Time

Shelf and fluvial style in a stable climate

river shelf

basin

Low water discharge

0 5 10 15 20 25 30

Time

Shelf and fluvial style in a stable climate

river shelf

basin

Low water discharge

0 5 10 15 20 25 30

Time

Shelf and fluvial style in a stable climate

river shelf

basin

Low water discharge

0 5 10 15 20 25 30

Time

Shelf and fluvial style in a stable climate

river shelf

basin

Low water discharge

0 5 10 15 20 25 30

Time

river shelf

basin

High water discharge

Shelf and fluvial style in a stable climate

0 5 10 15 20 25 30

Time

river shelf

basin

High water discharge

Shelf and fluvial style in a stable climate

0 5 10 15 20 25 30

Time

river shelf

basin

High water discharge

Shelf and fluvial style in a stable climate

0 5 10 15 20 25 30

Time

river shelf

basin

High water discharge

Shelf and fluvial style in a stable climate

river shelf

basin

High water discharge

Shelf and fluvial style in a stable climate

0 5 10 15 20 25 30

Time

Summary constant discharge

• Extent of erosion surface

• Fluvial stratigraphy

• Volume of lowstand sediments

Resulting only from a different constant water discharge

Conclusions• Interpretation of stratigraphy is not intuitive• Recognition of distinctive patterns in

stratigraphic architecture improves interpretation

• Analogue modeling helps to find these distinctive patterns in stratigraphic architecture

• Expansion of our database by less time-consuming methods is required