Hydraulic action
The force of waves compresses air into cracks in rocks. When the wave retreats, the pressure releases, causing the rock to weaken and break apart
Attrition
Rocks and pebbles collide with each other, breaking into smaller, smoother pieces.
Abrasion
Rocks and pebbles carried by waves are thrown against cliffs, grinding them down like sandpaper.
Solution
Seawater dissolves soluble minerals from the rocks, especially limestone and chalk.
how does longshore drift work
Waves approach the shore at an angle (controlled by the prevailing wind).
The swash moves material up the beach at the same angle.
The backwash pulls material straight down the beach under gravity.
This zig-zag motion moves sediment along the coastline.
suspension
fine material carried in water
traction
rolling large rocks
saltation
bouncing pebbles
solution
dissolved minerals
when does Deposition occur
Deposition occurs when waves lose energy and drop the sediment they carry.
what can deposition create
Creates beaches, spits, and other depositional landforms.
what is Weathering
breakdown of rocks without movement
Mechanical weathering
Physical breakdown, e.g. freeze–thaw, where water enters cracks, freezes, and expands, breaking rock apart.
Chemical weathering
Rocks dissolve or decompose due to chemical reactions, such as acid rain reacting with limestone.
Biological weathering
Roots, burrowing animals, and microorganisms break down rocks.
what is Mass Movement
downhill movement of rock and soil due to gravity
Rockfall
Fragments of rock break off steep cliffs.
landslide
Large blocks of rock slide down a slope.
Slumping
Saturated soil and weak rock slump down a curved surface.
mudflow
Wet mud and debris flow downhill rapidly.
