Alluvial Fans - PowerPoint PPT Presentation

About This Presentation
Title:

Alluvial Fans

Description:

Alluvial Fans – PowerPoint PPT presentation

Number of Views:728
Avg rating:3.0/5.0
Slides: 23
Provided by: JSW11
Category:
Tags: alluvial | duad | fans

less

Transcript and Presenter's Notes

Title: Alluvial Fans


1
Alluvial Fans
2
(No Transcript)
3
(No Transcript)
4
Depositional Model
5
The upper Fan EnvironmentErosion by streams and
glaciers
6
The Mid-Fan EnvironmentBraided Streams and
debris flows
7
Debris FlowsMore commonly known as mud slides or
flows. These are sediment gravity flows, meaning
that they flow as a mass of sediment under the
influence of gravity.The fine-grained matrix
(silt and clay) move as a highly viscous fluid
capable of transporting very large material in
suspension.
8
Stratigraphic Succession of the mid-fan consists
of interbedded braided stream deposits, debris
flows and sieve deposits
9
Distal Fan Deposits
10
Factors Controlling Fan Development-Fan
Progradation versus Retrogradation
  • Climate-stream discharge
  • Tectonics-uplift of source
  • Basin Subsidence

11
River Geomorphology
12
(No Transcript)
13
Factors Controlling Stream Geomorphology
  • Climate-stream discharge
  • Gradient
  • Substrate Conditions

14
Braided Rivers
  • High gradients
  • Flashy discharge
  • Minimal vegetation (arid)
  • High bedload

15
Little to know floodplainEphemeral channels
with low width to depth ratiosLow preservation
of barsGenerally coarse, poorly sorted deposits
16
Braided Stream Deposits
17
Mials Classifiction
18
Platte-Type Braided Rivers
19
Scott Type Braided Rivers
20
Troughs and Forsets are dominant
sedimentarystructures
21
Grain Size
22
Braided fan-delta complexes
Write a Comment
User Comments (0)
About PowerShow.com