1. Deposition Notes and Stream Life History Notes
Fill in the Blanks of Your Part 3 Note Packet for Unit 4.

2. Deposition Defined
Deposition- occurs when particles carried by erosion are
A. sedimentation- when the carrying power of a transporting agent and some of the particles are
- occurs in deep lakes, seas, or oceans.
B. _______________- when dissolved particles fall out of the water as it evaporates.
deposited somewhere else.
decreases
deposited
Precipitation
- forms the rocks limestone and rock salt

3. Factors Affecting Deposition
1. Particle size particles settle faster than particles.
- ___________- when a mixture of sediment sizes settles in still water or air, sorting into (beds) takes place. ( on bottom, on top)
large
small
sorting
horizontal layers
Larger particles
smaller particles
This shows vertical sorting
*Creates layers of sedimentary
rocks in oceans and lakes
Shale
Siltstone
Sandstone

4. Factors Affecting Deposition
- _________________________- vertical sorting within the bed.
Graded bedding
Notice the sorting within each layer.
- cross bedding- produced by and fast-moving
- sediments are deposited at
winds
rivers
an angle

5. Factors Affecting Deposition
2. Particle shape- smooth, rounded particles usually settle than angular, flatter particles.
3. Particle density particles will settle faster than particles.
4. Velocity of transporting medium- as velocity of water decreases, there is a loss of carrying power and the particles settle out first.
faster
higher density
lower density
larger, heavier

6. Factors Affecting Deposition
Horizontal sorting
5. _________________________________- as a stream or river enters a large body of water such as a lake or ocean,
its velocity decreases as distance from its mouth increases, producing horizontal sorting.
- larger, denser particles settle out first with the smaller, less dense particles carried farther
Velocity decreases
Deposition Animation
Smaller, lighter particles
Larger, denser particles

7. Factors Affecting Deposition
6. Particle velocity- particles in solution move at the velocity of the stream as do many of the colloidal particles.
- suspended particles move slower than the stream.
- largest and densest move slowest.
7. Glacial deposition
-__ ____- unsorted (all mixed together) rock material deposited directly by glaciers.
- ______________- rock material deposited by the meltwater of a glacier.
- can show horizontal sorting.
- ______________- large boulders deposited by glaciers
glacial till
outwash
erratics

8. Erosional-Depositional System
- ___________- where the river begins.
- river has its
- ___________- where the river ends.
- as the river flows toward its mouth the potential energy
- erosion- dominant when the slope is and the velocity of the river is
- source.
- deposition- dominant when the slope is and the velocity is
- mouth.
- the outside of a meander (curve) experiences while the inside of a meander experiences
source
greatest potential energy
mouth
decreases
steep
fast
(usually found here)
gentle
slow
(usually found here)
erosion
deposition

9. Youthful Stage 1. youthful- poor drainage
- lakes, waterfalls, and rapids. -
is greater than side cutting.
filled by the stream.
rapid stream flow, steep slope
down cutting
V-shaped valley
Notice the features listed above.
Great example is the Niagara River.

10. Maturity (Mature Stage)
2. maturity- occurs when becomes greater than down cutting. -
- flood plain- land between the and the of the valley that is usually covered by the stream during floods.
- rapids and falls are almost gone and the stream is now ____________ (has a smooth gradient).
- stream begins to over the valley floor.
- full maturity- occurs when the flood plain becomes wide enough to accommodate the meanders.
- ____________________ are produced when meanders are cut off.
side cutting
a flood plain starts to form
stream
steep walls
graded
meander
oxbow lakes

11. Maturity Diagram Good example is the Mohawk River
The stream is doing more deposition than erosion.
Notice that the flood plain is much wider, but not deeper.

12. Old Age Stage
3. old age- when the valley floor becomes than the river meanders can fill.
- natural levees (broad, low ridges along both sides of the stream) form during
wider
times of flooding
Best example is the Mississippi River
Soil particles deposited by flowing water

13. Erosional-Depositional Changes
delta
________- deposit of sediment formed at the mouth of a river where the river loses its carrying power as it enters a quiet body of water.
alluvial fan- a deposit of sediment formed where the velocity of a river as it flows out of the mountains onto the flatland.
slows
Dynamic Equilibrium
balance between erosion and deposition
near the mouth of a river
near the middle of a meander in the river