Deposition

➢ Deposition

o The __________ of sediments with a ______ of transport _________.

▪ Sediment is _______ _______ in a new location.

o Deposition resulting from gravity

▪ __________: collection of __________ sorted sediments

commonly found at the base of a cliff or rock outcrop.

o Deposition occurs when the velocity (speed) of running water or wind

_____________, and/or when the discharge (volume of water)

_____________.

➢ Factors Affecting the Rate of Deposition of Sediments

o Size

▪ As size increases, the rate of deposition ______________.

o Density

▪ As density increases, the rate of deposition ______________.

o Shape

▪ The rounder ( more ______________ ), the ___________ the

rate of deposition.

➢ Bedding

o Arrangement of sediment particles into distinct (obvious) ___________

of different sediment compositions or __________ __________.

( _________ sorted )

o May also be called ___________________.

o Each different layer often represents a shift (or change) in

______________ ___________.

o Types of bedding

▪ ___________ bedding

• Result of the fact that different particles will settle at

different __________.

o ___________ settle first and form the bottom layer

of the bed.

o __________ settle last and form the top layer of

the bed.

▪ __________ bedding

▪ Sedimentary layers deposited at an __________ to the underlying

set of beds.

▪ Wind or water current direction is indicated by the ___________

lines of deposition.

• Wind or water current direction (flow) was ____________

the _________ at the time of deposition.

➢ Ripple Marks

o Indicate the type of ____________

▪ _______________ ripples

• Current flow in ________ direction.

• Sediments roll up the gently sloping _____________ side

of each ridge and then cascade down the steeper

_______________ side.

▪ ______________ ripples

• Form from ____________________ motion of

__________ in the ____________ zones of a coastline or

the water’s edge in a lake.

➢ Barrier Island Formation

o Wave action as a result of ___________________ current eventually

deposits sediments along the coastline.

➢ Running Water Deposition

o When a stream enters a relatively still body of water, its speed will

________________ ; therefore, the _________________ of

sediments will occur.

▪ Deposition at the mouth of a stream entering a large body of water is

called a ______________.

▪ A _________ is an example of ________________ deposition of

sediments:

o Stream deposition similar to a delta can also occur on _________. This

Depositional environment is called an _______________ ________.

➢ Stream Erosion and Deposition

o Bends in a stream’s channel are called __________________.

o Meanders form in a _______________________.

o The stream’s velocity (speed) will change due to the curvature of the

channel.

o At the outside of the curve, the stream velocity ________________;

therefore, the process of _______________ occurs here.

o At the inside of the curve, the stream velocity _______________

(energy is ________ ); therefore, the process of ______________

occurs here.

o When the processes of erosion and deposition are ___________ to each

other, an __________________ has been reached.

▪ Stream velocity is ___________ at the point of _______________.

o Fill in the blanks with the words “equilibrium”, “deposition”, or “erosion”:

➢ Formation of an Oxbow Lake

➢ Stream Landscape Features

o Sediments deposited by water (or wind) tend to be ______ __________

▪ Examples are found in both horizontal and vertical (graded)

bedding.

➢ Glacier Deposition

o The _________ of a glacier moves __________ than the __________.

o Glaciers carry the _____________ range of sediment particle sizes.

▪ They pluck various rock sizes and _________ from different

locations during their journey and deposit them in other regions.

• This is the reason we can find rocks not native to our local

area in our local area.

o Sediments carried and deposited by glaciers tend to be ___________

____________ and can be more ______________ than the sediments

deposited by water and wind.

▪ This unsorted rock material is called ___________ (or glacial till)

o ________________ moraine

▪ Unsorted rock deposited along valley walls.

o _______________ moraine

▪ Unsorted rock in the center of where two glaciers merged into one

larger glacier.

o ___________ moraine:

▪ Unsorted rock trapped and deposited at the bottom of a glacier.

o ___________________ moraine:

▪ Unsorted rock deposited at the leading edge or “end” of the

glacier.

➢ Landscape Features of Glaciers

1._________

▪ A cone-shaped hill made of sediment deposited by meltwater.

2. ____________

▪ A _________ _________ shaped hill of glacial moraine.

▪ Its “tip” points in the direction of glacial movement.

3. ____________

▪ Large boulder deposited by the retreating ice.

4. ___________ _________

▪ A lake formed when a large block of glacial ice melts.

5. ____________ ___________

▪ A stream that is divided into an interlocking system of channels.

6. ____________ __________

▪ Layers of sediment deposited by melting glacial ice.

7. _____________ ____________

▪ Mass of lose and poorly sorted rock that forms a ridge marking the

farthest position reached by the glacier.

8. ___________ ____________

▪ Material deposited as the glacier retreats.

9. __________

▪ A ridge-like hill of deposits resulting from a stream flowing in a

tunnel under the glacier.

➢ Ice Ages

o There is evidence of at least _____ major ice ages during the last _____

million years.

▪ The time period between ice ages is called an

_________________ period.

▪ The most recent ice age ended only about ___________ years

ago.

➢ Depositional Environments

o Previously discussed cross bedding and ripple marks.

o Poorly sorted, angular sediments

▪ __________ transportation time.

▪ Large sediments are moved by ________ moving water

▪ Evidence of: __________________ activity

__________________

o Well sorted, rounded sediments

▪ __________ transportation time.

▪ __________ sized sediments.

▪ Settle in ________, ________ water.

▪ Evidence of:

• ________________

• Large ___________

o Limestone / Fossils

▪ Calcium carbonate (calcite) from shells of marine creatures.

▪ Evidence of :

• Warm, ____________, water

o Coal

▪ Evidence of a former ______________

o What happened at this location in the past?

o In what order were these layers formed?

o What layer was deposited AFTER the fault?