Page 1: Coastal Processes and Landforms

This page delves into the fundamental concepts of coastal geography, focusing on coastline types, erosion processes, and sea level changes.

Coastline Types

The page begins by explaining the difference between concordant and discordant coastlines.

Definition: A concordant coastline is characterized by alternating hard and soft rock layers that run parallel to the sea, while a discordant coastline has rock layers perpendicular to the sea.

Example: Lulworth Cove is cited as an example of a concordant coastline, while Swanage Bay to Poole Harbour represents a discordant coastline.

Coastal Erosion Processes

The text then explores various coastal erosion processes:

1. Hydraulic Action: Air trapped in cliff joints is compressed by waves, weakening the cliff structure.
2. Attrition: Waves cause rocks and pebbles to collide, breaking them into smaller pieces.
3. Abrasion: Rock fragments in waves grind down cliff surfaces.
4. Corrosion: Weak acids in seawater dissolve certain types of rock.

Highlight: The formation of wave-cut notches is explained as a result of abrasion and hydraulic action eroding the cliff edge.

Sea Level Changes

The guide discusses two types of sea level changes:

1. Eustatic: Global changes in water quantity due to climate change and melting ice sheets.
2. Isostatic: Local changes due to the depression or rebound of land after ice sheet removal.

Vocabulary: Rias are defined as flooded river valleys, while fjords are flooded glaciated valleys.

Beach Types

The page contrasts summer and winter beaches:

• Summer beaches: Formed by constructive waves with strong swash and weak backwash, resulting in steeper slopes.
• Winter beaches: Shaped by destructive waves with weak swash and strong backwash, creating shallower slopes.

Example: The text mentions that Scotland and the Isle of Arran have experienced isostatic rebound, with raised beaches 5m above sea level.