deposition-sedimentation the processes that release eroded materials causing sediments to settle...
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Deposition-SedimentationDeposition-Sedimentationthe processes that release eroded materials causing sediments to settle into a new
location. A. Cause of Deposition:A. Cause of Deposition:
1. A Decrease wind or water current velocity.
Mass Movements
Sand Dunes
Glacier
Moraine
Lake Bed
Beach
Flood Plain
Delta
B.B. Factors of deposition:Factors of deposition:
Particle Characteristics
1. Density: High density sediments settle at a high rate.
2. Shape: Round particles settle fast before flat sediments.
3. Size: Larger particles settle faster than small particles.
Aluminum 2.7 g/ml
Lead 6.5 g/ml
C. C. Patterns of deposited sedimentsPatterns of deposited sediments
1. Sorted Sediments:
Generally have the same size, shape, & consistency.
2. Unsorted Sediments: Mixed sizes of sediments.
Glacial Till
Poorly Sorted
3. Vertical Sorting:
In sediments of mixed size, the largest particles will settle to the bottom first with smaller material on top.
4. Graded Beds:
Show alternating layers of vertical sorting caused by cyclic events like seasonal floods.
5. Horizontal Sorting: Particles are sorted by size; as stream velocity decreases, the largest particles are deposited first followed by sands, silts, clay.
• Sediment burial with
compaction & cementation
resulting in lithification.
6. Wind Deposits:
Sediments which are sorted into tilted layers show cross bedding. The angle indicates the direction of current.
Erosion-Depositional System:
Kinetic & Potential Energy exists within a stream. When the amount of material lost from erosion is the same gained by deposition a dynamic equilibrium is reached.
Erosion-Depositional System A balance between erosion & deposition. (KE vs. PE)
1. Straight Channel
-Velocity Greatest In____________
-Erosion______________________
-Deposition____________________
2. Curved Channel
-Velocity Greatest _______________
-Erosion_______________________
-Deposition_____________________
Stream Velocity controls deposition
Largest particles drop out first as flow decreases.