Barrier Islands

Barrier Islands

Which of the following INCREASES as sediment becomes more

mature?

A. Grain size

B. Angularity

C. Sorting

D. None of the above

Which of the following is in the intertidal zone?

A. Swish zone

B. Swash zone

C. Infiltraton zone

D. Ripple zone

What is the main sediment transport mechanism in the

supratidal zone?

A. Wind

B. Waves

A. Summer Profile

B. Winter Profile

Barrier Island Systems

• Common along Passive Margins

• <100m to kms in width

• Sand is most common material

• Gravel common in glacial terranes

Cape Hatteras

Long-shore current: moves down beach as a result of waves coming into beach at an angle

Barrier Environments

• Beach– Dynamic part of barrier– Sediment moves in and out of beach with

storms

• Barrier Interior– Frontal dune ridge, secondary dunes

• Landward Margin– Intertidal sand or mudflat– Overwash deposits

Barrier Types

• Barrier Spits

Recurved Spit

Tombolo