Mass movement is the down slope movement of unconsolidated rock and soil (regolith). It consists of four main types of movement, see below. The diagram on p87
Core Higher is a useful aid.
1) Rockfalls/Scree Slopes
2) Landslides/Slumping
3) Flows
4) Soil Creep
Rockfalls/

Quickest of all the types of mass movement

Varying sizes of rocks involved

Often from steep cliff faces

More effective on well jointed rocks

Freeze/Thaw effect on cracks

Causes gravitational fall

Often largest rocks at bottom as bounce further
Scree Slopes (Talus Slopes)

Scree slopes directly beneath cliff face

Angle of slope between 33

and 38

gradient

Movement of rocks encouraged by Freeze/Thaw

Landslides

A fast movement of large amounts of material

Can occur more slowly every day

Often involves large sections of a slope moving in one go

Movement along slip planes where rock is weaker

Often along bedding planes , which have weathered , likely to be chemically weathered

Surface material often made heavier, so slides, due to weight of water

Often permeable rocks as hold water better in cracks etc

An impermeable base lubricates these slip planes as does heavy rainfall
Slumping/Rotational Slippage/Landslips

When rock slumps along curved sheer planes (slip planes), rotational slippage

Where harder, slow eroding rock , overlies a softer fast eroding rock

Collapse of hard rock as weak rocks undercuts it

Heavy rain and water content add pressure or weight and help lubricate the process

Again permeable upper and impermeable lower layers have an influence, see landslides

Large sections break away

Often found on coastlines

Former surface tilted backwards towards land

Mudflow

Can be both quick and slow, but usually regarded as fast see diagram p87 Core Higher

Again a high water content from rain for weight/lubrication , also wet winters

Acts like a flow of water

Again permeable surface and impermeable under layer

Forms a fan like debris deposit

Angle of slope quite gentle >10

gradient

Often occurs where little vegetation on slope, no roots to bind soil or interception
Solifluction

A slow form of flow

Saturated soil on top of permafrost

Flows in tongues to form lobes or terraces

Occur in Summer months when top soil thaws

Slowest form of mass movement

Occurs on gentle slopes of 5

gradient

Vegetation cover can be present

Caused by repeated expansion/contraction of soil

Water freezes and soil particles pushed up , on thaw sink down in a down slope movement.

Rain water causes soil to expand vertically , on drying it contracts and falls down slope

Terraces form, cracks and soil deeper down slope