The World Ocean (Ch. 10)

What are beaches made of?

Whatever type of sediments are locally available

Which beach zone would you find turbulent water with crashing waves?

Surf zone

What type of sediment would be most common on beaches near mouths of rivers?

Fine-grained silt and clay

Which of the following is NOT a characteristic of a summer-time beach?

Large boulders exposed, sand store in offshore sandbar

Where is beach sand 'stored' during the winter-time?

Offshore sand-bars

Longshore drift of sediment occurs how?

Swash transports sand up the beach face at angle, and backwash transports sand straight down the beach face

A coastal cell is composed of ____ that transport sand to shore, -____that distribute the sand along the shoreline, and _____ that transport the sand to the deep-sea.

Rivers/ longshore currents/ submarine canyon

At a beach, the annual input of sand is 5,000 m° and the annual output of sand is 4,500 m3. What would you expect will happen to this beach over time and why?

It will accrete because more sand is gained than lost

Why is Assateague Island, VA disapearing?

Jetties and groins built in Ocean City MD are causing sediment starvation

Why are groins only partly successful in preventing coastal erosion?

They increase the net deposition of sand on the side facing the waves (upstream), but cause net erosion on the side opposite (downstream).

In the longshore drift of sand and water, the upward surge onto the beach face is the ____ and the downward flow is called the ____.

swash/backwash

Which one below is a 'service' provided by dune plants?

They help stabilize the dune by slowing erosion.

Which of the following process would likely happen on a stretch of beach located on the downstream side of a groin?

erosion

A coastal cell is composed of what following features?

river, longshore current, and submarine canyon

The proximal cause for longshore drift of sand is what?

waves hitting beach at an angle

You are constructing a sand budget for the area of the coastline for your town's beach. Which process should you consider as contributing to sand inputs?

longshore transport towards your beach

What should you do if you are caught in a rip current?

drift and wait until you're out of the rip current and then swim ashore