The document discusses geomorphic processes that shape the Earth's surface. It describes both endogenic forces from inside the Earth like tectonic activity, and exogenic forces from outside like weathering and erosion powered by the atmosphere. Exogenic processes mainly wear down land through weathering, mass wasting, erosion, and deposition. Weathering breaks down rocks through physical and chemical means. Mass wasting transfers material down slopes through gravitational forces. Erosion then transports this material, which is eventually deposited through aggradation elsewhere. These geomorphic processes continually reshape the uneven surface of the Earth.

1. 6.
GEOMORPHIC PROCESSES

2. Why is the surface of the earth uneven ?
• The earth surface is being continuously
subjected to by External forces originating
within the earth atmosphere and by the
internal forces within the earth.
• The external forces are known as EXOGENIC
forces.
• The internal forces are known as
ENDOGENIC forces.

3. 1. Degradation
2. Aggradation
3. Gradation

4. • The ENDOGENIC forces are mainly land
building forces.
1. Diastrophism
2. Volcanism
• The EXOGENIC processes are mainly land
wearing forces.
1. Weathering
2. Mass wasting/Movement
3. Erosion
4. Deposition

5. GEOMORPHIC PROCESSES
The endogenic and exogenic forces
causing physical stress and chemical
actions on earth materials and
changes the earth surface.

6. GEOMORPHIC AGENTS
• Any exogenic element of nature capable
of acquiring and transporting earth
materials.
1. Running water
2. Moving ice mass
3. Wind
4. Waves and currents

7. ENDOGENIC PROCESSES
• The force is mostly generated by
1. Radioactivity
2. Rotational and tidal friction
3. Primordial heat from the origin of the
earth.

8. DIASTROPHISM
• All processes that moves, elevate or build
up portions of the earth crust.
• They include
1. Orogenic Processes – mountain building
2. Epirogenic Processes – continental building
3. Earthquakes – minor movements
4. Plate tectonics – horizontal movements of
crustal plates

9. EXOGENIC FORCES
• These forces derive their energy from
atmosphere.
• Force applied per unit area is called Stress.
• Temperature, precipitation and structure of
rocks are important elements that control
various exogenic processes
• All the exogenic processes are covered under
a general term DENUDATION.
• The word DENUDE means UNCOVER.
 Weathering, Mass wasting/Movement, Erosion
and Transportation are included in denudation

10. DENUDATIONAL PROCESSES
WEATHERING
MASS
MOVEMENT
EROSION/
TRANSPORTATION
GRAVITATIONAL/
STRESS OR
CHEMICAL
ACTIONS
GRAVITATIONAL
FORCES
KINETIC
ENERGY
ENERGY
PROCESS
The effects of most of the exogenic processes are
small and slow

11. WEATHERING
• Mechanical disintegration and chemical
decomposition of rocks.
• As very little or no motion of materials takes
place in weathering, it is an in-site or on-site
process.
• Weathering processes are conditioned by
many complex geological, climatic,
topographic and vegetative factors.
• Weathering processes vary from climate and
depth.

12. weathering
Chemical
weathering
Physical
weathering
Biological
weathering
Very rarely does any one of these processes ever operate
completely by itself but dominance of one processes can be
seen.

13. Chemical
weathering
solution
carbonation
hydration
Oxidation
&
reduction

14. Physical weathering
• Physical or mechanical weathering processes
depend on
1. Gravitational forces
2. Expansion forces due to temperature changes or
animal activity
3. Water pressure controlled by wetting and drying
cycles

15. UNLOADING AND EXPANSION
TEMPERATURE CHANGES AND
EXPANSION
FREEZING AND FROST
WEDGING
PHYSICAL
WEATHERING

16. EXFOLIATION
Exfoliated Domes
Exfoliated Tors

17. BIOLOGICAL WEATHERING
1. Human Activity
2. Small organisms and dead animals
3. Leaves and roots of trees

18. MASS MOVEMENT
 Transfer the mass of rock debris down the
slopes under the direct influence of gravity.
 Mass movements are aided by
 Gravity
 Weathering
 Weak unconsolidated materials
 Steep slopes
 Abundant rains
 Scarcity of vegetation

19. CAUSES OF MASS
MOVEMENT
1. Indiscriminate removal of natural
vegetation.
2. Earthquakes.
3. Overloading through addition of materials.
4. Removal of materials from the slope.
5. Overloading due to heavy rainfall.
6. Increase in gradient and height of slope.

20. TYPES OF MASS MOVEMENTS
1. Slow Movement
2. Rapid Movement

21. SLOW MOVEMENT
• Occur on moderately soil covered slope,
movement of materials is extremely
slow.
1. SOIL CREEP
2. TALUS CREEP
3. ROCK CREEP
4. ROCK- GLACIER CREEP

23. SOLIFLUCTION
Which involves slow down slope
flowing soil mass or fine grained rock
debris saturated or lubricated with
water.
• common in moist temperate areas

24. RAPID MOVEMENTS
• Mostly occur in humid climatic region over
gentle to steep slopes.
• Earth flow – movement of water
saturated clay
• Mud flow – along a definite channel
• Debris avalanche – narrow tracks and
steep slopes, faster than mudflow
• Snow avalanche .

25. Snow Avalanches

26. LANDSLIDES
• These are relatively rapid and perceptible
movements.
• The materials involved are relatively dry.
1. Slump - slipping of rock debris with
a backward rotation
2. Debris slide
3. Rock slide

27. LANDSLIDE

29. EROSION
• Application of the kinetic energy
associated with the agent to the surface of
land along which it moves.
• involves acquisition and transportation of
materials.

30. SOIL
• Collection of natural bodies on the earth
surface, contains minerals, water, air,
living organisms and dead matters.
• Pedology is soil science.
• Pedologist is a soil-scientist.
• Soil is a dynamic medium in which many
chemical, physical and biological activities
go on constantly.

31. SOIL-FORMING FACTORS
1. Parent material
2. Topography
3. Climate
4. Biological activity
5. Time