Coastal Processes Quiz

Coastal Processes

• Erosion: The breakdown and wearing away of rocks and materials by wind, water, or ice. Can be chemical or physical.
• Transportation: The movement of eroded material from one location to another.
• Deposition: The dropping of sediment carried by wind, water, or ice when the transporting force loses energy, forming coastal features from accumulated sediment.
• Coastal Erosion: The sea's force reshapes the coastline. Wave energy directly relates to erosion strength. Wave size is influenced by wind speed, duration, and fetch (distance over water).
• Hydraulic Action: The forceful crashing of waves against cliffs. Compressed air in cracks widens and deepens them, weakening the rock.
• Abrasion: Rocks colliding, wearing each other down, becoming smaller, smoother, and rounder.
• Attrition: Rocks and pebbles carried by waves striking against cliffs, breaking apart and becoming smaller.
• Corrosion (Solution): Chemicals in seawater (salts and acids) dissolving rock minerals, breaking them down over time.
• Erosion Speed: Dependent on the force of water and the rock's durability.

Coastal Landforms: Headlands & Bays

• Headlands: Prominent sections of cliffs jutting into the sea, composed of hard, resistant rocks (e.g., granite) that erode slowly.
• Bays: Areas where soft rocks have eroded away, located between headlands. Usually feature sandy beaches. Soft rocks (e.g., chalk, limestone) erode quickly.
• Caves, Arches, Stacks, Stumps: Sequence of erosion features that occur as headlands are eroded. A cave widens and forms an arch, that erodes and collapses, leaving a stack, which weakens and becomes a stump.

Wave-Cut Platforms

• Formation: Sea erosion of a cliff base creates a wave-cut notch. A widening notch weakens the cliff, causing it to collapse. The collapsed material is then transported, leaving a wide, sloping platform.

Longshore Drift

• Process: A zig-zag movement of sediment parallel to the shoreline. Driven by waves at an angle to the shore.
• Prevailing Wind: The direction of the wind dictates the direction of longshore drift. Wind direction influences wave direction, which in turn determines the sediment's movement.
• Swash & Backwash: Movement of water up the beach after a wave breaks and the back movement down the beach due to gravity. The strength of these forces determines the type of wave.

Coastline Features: Spits, Beaches, Tombolos, Bars, Salt Marshes

• Spit: An elongated stretch of sand extending from the coast into the sea, often connected to the mainland at one end. Formed by longshore drift.
• Hook: A spit with a curved end due to changes in prevailing wind direction.
• Beaches: Accumulations of eroded material deposited by waves in shallow water. Sandy beaches occur in sheltered bays, due to lower wave energy. Pebble beaches are in areas with higher wave energy.
• Backwash & Swash: Swash moves water up the beach; backwash moves it back down, causing erosion and transportation.
• Constructive Waves: Build up beaches as backwash is weaker than swash. Low-energy waves that deposit material. Waves are low and spaced apart.
• Destructive Waves: Cause erosion because strong backwash removes sediment. High-energy waves that break downwards with high force. Waves are steep and close together.
• Tombolo: A spit connecting an island to the mainland.
• Bar: A strip of deposited sand that traps seawater (lagoon) forming behind it.
• Salt Marsh: A sheltered wetland area behind a spit or sandbar, flooded and drained by tidal saltwater.

Test your knowledge on coastal processes such as erosion, transportation, and deposition. This quiz covers the key mechanisms involved in shaping coastlines, including hydraulic action and abrasion. Perfect for students studying geography or environmental science!