• Geo (earth)

• Morpho ( form/ structure )

• Logy (description /study )

Literal meaning ~ study of earth forms.

It explains the form of the earth surface

"Study of landforms"

"Study of earth structure "

• Geomorphology =subfield of physicalgeography.

• study of origine and evolution of landforms.

• focus on processes shaping earth's surface.

Father of geomorphology - William Morris Davis

Introduced the cycle of erosion

cycle of erosion

1. Youthful stages

2. Mature stages

3. Old age stages

4. Rejuvenation stages

Explores the processes create and shape landforms.

covers weathering, erosion, deposition and tectonic activity.

Make the earth's crust move, mostly at plate boundaries.

• Two types

  1. Diastrophism (slow movements)

  2. Catastrophism (sudden movements)

Rocks to move horizontally and vertically.

Includes folding, faulting, uplifting of the crust.

Two types

1. Horizontal movements

2. vertical movements

Horizontal movements

orogenic movements.

cause disruption of the horizontal layers of rocks through lateral displacement.

Creates mountain ranges (lateral displacement)

Compression (pushing)

tension (pulling)

Earth's crust gets uplifted, forming tall mountains

tension (pulling)

Forces of compression.

Compression-rocks fold or break.

forms fold mountains

ex.Himalaya

Rockies

Andes

Alps

Folding is the bending of rock layers.

it happens due to compression in the earth's crust

Parts of a fold.

Anticline- upward

Syncline-downward

Limb -side of the fold

Crest- highest point

Axial plane- middle dividing

Hinge line- line of maximum bend

Type of fold

1. Symmetrical folds

2.Asymmetrical folds

3.Overturned folds

4.Recumbent folds

5.Isoclinal folds

Types of faults

1. Normal fault.

2. Reverse fault.

3. Transform fault/ shear fault / strike-slip fault.

1. Normal fault is caused by tension. footwall block- above the fault hanging wall block-below the fault.

2. Two fractured blocks move toward each other on block rises above the other

3. Rockslide sideways. fault- block mountains -crust blocks uplifted and tilted ex. Sierra navada , USA

Epeiric-continents

Genic - origin

Epeirogenic - origin of continents

Called continent - building movements.

Form continents and platens

Sudden movements

Break the earth's crust Gas, Ash , Magma, escape to the surface

Occurs at the tectonic plate margins.

Cause rapid deformation of the crust.

ex. Earthquakes.

Volcanic eruption

Caused by external forces

ex.Weathering

Erosion

Deposition

mass wasting

Exogenic processes

1. weathering, erosion, deposition

2. mass movements transportation

Weathering

Rocks breaks down.

due to climate,plants,animals,other living organisms

Types

1. physical

2. chemical

3. biological

Physical weathering

Rocks break down due to weathering

Types

1. Thermal weathering (due to heating or cooling)

2.Frost wedging (due to freezing and thawing process)

3.Exfoliation (slowly peel off)

Types

1. Solution

2. Oxidation

3. Hydrolysis

4. Carbonation

5. Hydration

Mass movements

Rocks and soil slide down due to gravity.

Mass movement or mass wasting

Happen suddenly or slowly.

Type of material (mud,soil,rock)

Type of motion

Factor affects mass wasting

Human activities can cause mass movements

ex. building heavy structure, roads, near a steep slope

Preventive actions for mass movements

prevention- divert water, use nets, fences, retaining walls and educate people.

Types

Glacial erosion- by ice

Fluvial erosion- by rivers

Coastal erosion- by sea waves

Wind erosion- by the wind

Agents of erosion

water

wind

ice

Transportation

Movements of rocks and sand by natural agents.

Agent of transportation

Running water

Wind

Ice

Waves.

1. Extrusive igneous landforms (volcanic)

2. Intrusive igneous landforms(plutonic)

   Intrusive-magma cools

   underground

Intrusive- underground

slow cooling

coarse

large grains

Extrusive - surface

fast cooling

fine

small grains

Intrusive bodies

Types

1. discordant

2.concordant

Intrusive igneous landform

plutons

form below the earth's surface surrounded by other rocks. (Sedimentary or metamorphic)

remain as old magma

chambers of volcanoes.

exposed by erosion and weathering

appear as hills, mountains, flats/ tabular rock.

Batholith

A huge igneous rock mass formed when magma cools inside the crust

can spread over hundreds of km

several km thick

formed from many plutons

Material include

Lava flows

pyroclastic

Volcanic bombs

Ash

Dust

Extrusive igneous land forms

Cinder cones

Shield volcanoes

Composite volcanoes

Lava domes

Caldera

Volcanic hotspot

Active, dormant, extinct

Eruption style

Central, fissure

Hawaiian, stromboli, volcanic pelean

Types of volcanoes.

Active Volcanoes

Erupt frequently

ex. mount etna

barren island

Dormant volcanoes

Inactive for a long time

Release gases or steam

ex. Mount Kilimanjaro

Tanzania

Extinct volcanoes

No longer erupts

Vent closed with solidified lava

ex. Mount Kenya, Fuji

shield volcanoes

cinder cone volcanoes

composite

caldera

Shield volcanoes

Broad and gentle in shape.

lava spreads far and wide

ex. Hawaiian

Usually quiet

sometimes explosive with water

Cinder cone volcanoes

Size-small

Contains very little lava

Have steep sides with a small crater on top

Made of loose cinders (scoria)

Composite

Tall, cone- shaped volcanoes

Built of layers of lava, ash and cinders

Known for violent, explosive eruptions.

Caldera

Most explosive volcanoes.

Eruption causes the volcanoes

to collapse, forming a large depression

much bigger than a crater

show a huge magma chamber underneath

Divided into three types

1. Generic classification of landforms

2. Genetic classification of landforms

3. Scale and lifespan of landforms

Generic classification of landforms

Group of landforms

ex. mountains

plateau

plains

Based on process the form them

• Volcanic landforms (Intrusive/Extrusive/Igneous)

• Fluvial (River/Streams)

• karst (Soluble rock erosion)

• Aeolian (Wind action)

• Coastal (Waves and tides)

• Glacial (Glaciers)

Scale and life span

Landforms by scale and lifespan

• 1st order (large): continental landmasses, ocean Basins

• 2nd order (medium): plains, plateau mountains

• 3rd order (small): valleys, canyons, dunes.

Branch of physical geography

Study of landforms shaped by running water

Drainage basin

Land area where all water flows into a single river or outlet

Elements

Catchment area

Watershed

Source

Confluence

Tributary

Mouth

: Horton

: Arthur

: Strahler (1952)

Classifies streams by number of tributaries

Shows river size and hierarchy

• 1st order - no tributaries

• 2nd order - two 1st order join

• 3rd order - two 2nd order join

Lower order joining higher order doesn't change order

Couties using stream ordering

United states

United Kingdom

Canada

Australia

Germany

India

River flows from mountains to the sea

Upper course-fast and narrow

Middle course-wider and slower

Lower course - slowest and widest

River course- path from source to mouth with different features along the way

Cross-sectional shape of a river

Side view of a river

• V-shape

• U-shape

• Flat shape

  
  

Involving running water

Key processes

• Erosion

• Transportation

• Deposition

River erosion

Fluvial erosion- river wears away the land

Depends on river speed

Type

• Vertical (downward, upper course)

• Lateral (sideways, middle lower course)

Main process of erosion

1. Hydraulic action

2. Abrasion

3. Attrition

4. Solution

Methods

Suspension

Traction

Solution

Saltation

River deposition

When river lose energy, they drop sediment

Large boulders settle first; fine clay is deposited last.

Upper course

Youthful stages.

Narrow, fast flowing

River with less water

Dominated by vertical erosion

Source: starting point of river

Tributaries: streams joining the main river

Middle course

Matures stage

Wider and deeper with moderate flow

Lateral erosion widens the valley

Water volume increases, slope is gentle

Lower course

Wide slow river

flat food plains

Main activity deposition

shallow river depth

When river splits into smaller chanels

The main landforms created by river deposition include

1. River deltas

2. Floodplains

3. Levees

4. Alluvial fan

• Intrusive and extrusive landforms

• Fluvial landforms

• Aeolian landforms

• Karst landforms

• Coastal landforms

• Glacial landforms

Aeolian terrains are shaped by wind through

Erode

Transport

Deposit

Types of wind erosion

• Deflation (Materials carried by the wind abrasion and grind rocks)

Aeolian Transportation

Three types

1. Suspension (wind carried than 0.1mm particles)

2. saltation (wind carried between 0.1-0.5mm particles)

3. Creeping (large rock particles creeping or roll over smash and move along the surface)

Aeolian Deposition

Aeolian deposition happens when wind drops sediments due to low speed, obstacles or heavy load

Erosional Aeolian landforms

Ventifacts

Desert payment

Deflation hollows

Mushroom rock

Yardang

Aeolian depositional landforms

Sand dunes

Loess

Karst forms when acidic water dissolves limestone, creating caves, sinkholes and underground streams.

Factors affecting Karst landforms formation

1. Lithology (solubility of bedrock)

2. Climate

3. Structure

4. PH content in water

5. Time

Limestone features

Above ground

ex. Sinkholes - (Guatemala City sinkholes, national corvette museum Skydome)

Doline

Lappies

Uvala

Polje

Caves

Below grounded (from deposition)

Curtains

Stalactite

Stalagmite

Pillar

Countries researching karst topology

China (Guilin)

USA (Florida, Kentucky, mammoth cave)

Italy (Apulia)

Slovenia

Vietnam (ha long bag, Ninh Binh)

France (causse da quercin)

Sections of a coast

Foreshore (Intertidal zone)

Backshore

Nearshore

Offshore

Coastal zones

Land-sea transportation areas shaped by waves, winds, and extreme events with variable erosion and deposition.

Coastal zones are used for

Fishing

Transport

Recreation

Waste disposal

tidal/wave energy

Coastal zones are they link the

Atmosphere

Ocean

Land and transfer sediment from land to sea

Type of waves

1. Created in calm weather less powerful

They deposit material, building up Beachers

2. (Backwash) Destructive waves

   Created instorm

   Conditions

   Stronger

   Erode the coastline

   
   

   Coastal erosion

   Four types

   1. Solution(corrosion)

      acids in seawater dissolve rocks lick chalk and limestone

   2. Abrasion

   sand and rock fragments in water grind against cliffs

   3.Hydraulic action

   water and waves break down rocks by force

   4. Attrition

   waves smash rocks and pebbles together, making them smaller and smoother

   
   

   Coastal Erosional Landforms

   • Headlands

   • Bays

   • Caves

   • Stacks

   • Arches

   • Stumps

   • Waves-cut platform

   Coastal transportation

Four Types

1. Suspension

   small particles

2. Solution

   minerals dissolved water

3. Saltation

   small pieces of shingle

4. Traction

   pebbles and larger sediments

   
   

   Coastal Deposition

   Coastal deposition occurs when the sea loses energy and forms landforms by depositing materials

   
   

   Coastal depositional landforms

   Landforms

   Beach

   Spit

   Bar

   Tombolo

   Type of Beach

   Sandy

   Rocky

   Frozen

   Tropical

Large bodies of ice glaciation are the movement of glaciers that carve

Landscapes: UK shows their effect in the lake district and glaciers remain in the alps study of ice

It is effect, in Britain, ice once covered large areas up to 3km thick

We can find ice

1. Polar ice caps (Antarctic, Arctic)

2. Frozen lakes and rivers

3. Permafrost (A layer of permanently frozen soil and sediments)

Bodies of ice

1. Glaciers (Alpine and ice sheet)

2. Ice bergs

3. ice sheets

4. sea ice

Alpine Glaciers

Known as mountain glaciers many parts of the world

Ice sheets

Polar regions near the earth's poles

• Antarctic ice sheet

• Greenland ice sheet

1. Zone of accumulation (snow and ice add up)

2. Zone of ablation (ice melts or is lost)

Process of Glacial

Inputs

Snow

Rain

Processes

Accumulation

Ablation

Plucking

Abrasion

Transportaion

Out put

Meltwater

moraine

Action of Glaciers

1. Erosion (plucking and Abrasion)

2.Transportation

3.Deposition

Erosional landforms of Glaciers

U-shaped valley

Cirque and tarn

Aretes

Horn

Nunataks

Glacial Deposition landforms

1. moraines (lateral medial Terminal ground)

2. Drumlins

3. Erratic

Types of moraines

1. Ground moraines

2. Lateral moraines

3. Terminal moraines

4. medial moraines