The video explains how waves impact shorelines, causing erosion and shaping landscapes. It covers beach erosion, the formation of sea stacks and caves, and how sediment deposition forms beaches. The type of sand on a beach depends on the rock it originated from, such as volcanic or granite. The video also discusses the formation of sand bars and spits.

What is the primary process by which waves shape the shoreline?

• Erosion of rocks

• Creation of sandbars

• Formation of sea stacks

• Deposition of sediment

How are sea stacks formed?

• By human intervention

• By volcanic activity

• By erosion of less resistant rock

• By deposition of sand

What determines the type of sand found on a beach?

• The color of the water

• The temperature of the region

• The type of rock from which the sediment originated

• The amount of sunlight

What are sandbars?

• Deep underwater trenches

• Man-made structures to prevent erosion

• Large rocks found on the beach

• Long ridges of sand deposited by waves and currents

Where does the black sand on Icelandic beaches originate from?

• Coral reefs

• Volcanic rock

• River sediment

• Granite rocks