1. ENDOGENOUS PROCESSES AND ASSOCIATED LANDFORMS

2. THE EVER CHANGING LANDSCAPE
Earth’s surface is ever changing
Endogenous processess- interior of the earth
Mountains, plateaus and plains formed
Occurences of volcanoes and earthquakes
Processess- slow and sudden
Many areas rise or subside

3. NOTABLE CHANGES Breaking of Gondwanaland 120 mya
Indian peninsula started drifting towards north
Took present shape around 40 mya
Raising of Himalayas- present height during last 1 million years.

4. FORCES OF DIASTROPHISM
Folding
Faulting
Uplift
Depression
Act Very slowly
Effects visible after thousands of years
Two types of diastrophism
Vertical forces
Horizontal Forces

5. VERTICAL FORCES Continental rise and sink
Upward forces- Uplift
Downward forces- Subsidence
Do not disturb the horizontality of rock layers
At the most, layers may be inclined or tilted.

6. HORIZONTAL FORCES Mountain- building forces
Act in a horizontal direction
Disturb horizontal layers of rocks
Compression- body pushed from opposite sides
Tension- Rocks are pulled apart

7. FOLDING Bending of horizontal layers of rocks
Tilting or twisting of rock strata
Caused by compression
Formation of series of crests and troughs
Anticlines & synclines
Anticlines- limbs incline in different directions
Synclines- limbs incline in same direction

8. TYPES OF FOLDS
Symmetrical folds- both limbs equally bent, inclined at almost equal angles to the horizontal.
Asymmetrical folds- one limb pushed too far, one side gradual slop, other side steeper
Monoclinal fold- one fold is vertical
Isoclinal fold- both sides are inclined in the same direction
Recumbent fold- one limb is pushed over the other, both limbs are parallel to each other
Overthrust fold- fracture occurs, one limb slides forward over the other limb.

9. FAULTING Result of tension
Rock strata cannot withstand tension, breaks
Displacement along the fault plane.
Normal Fault- blocks move in opposite direction, fault plane has steep slope
Reverse Fault- produced by compression, hanging wall slips up, gentle fault plane
Thrust Fault- one block thrusts upon the other, may result in formation of folds

10. LANDFORMS ASSOCIATED WITH ENDOGENOUS PROCESSES
First Order Landforms- continents and oceans
Second Order Landforms- mountains, plateaus and plains
Third Order Landforms- hills, valleys, deltas etc
Mountains- 26%
Plateaus- 33%
Plains- 41%

11. MOUNTAINS Uplifted part of the earth from the surrounding area
At least 900 m asl, broad base, very high, steep slope and narrow peak.
Less than 900 m, landforms are called hills
Fold
Block
Volcanic
Dissected

12. Fold Mountains Folding of sedimentary rock strata
These were located in areas of narrow, elongated seas or lake basins- geosynclines
Either folded from both sides
Or one edge may be stable, other side is moving which may squeeze the sediment
Old Fold mountains
Young Fold Mountains

13. Block Mountain Formed due to creation of faults caused by tension
Block mountains and grabens
Flat tops, steep sides, flat bottomed rift valleys

14. Volcanic Mountains
Lava thrown out and deposited around the crater forming a mountain
Also known as mountains of accumulation
Thinner lava ( Basic), shield volcano
Thicker lava( Acidic), conical volcano

15. Dissected Mountains Eroded by dynamic agents
Worn down from previously elevated regions
Nilgiris
Girnar
Rajmahal Hills

16. Influence of mountains on humans
Climate- climate barriers
Vegetation- variety of forests, rich timber, pastures, raw materials for agro-based industries
Minerals- Coal, Iron ore, gold, silver, gems, oil
Rivers- source in he mountains, perennial, form fertile alluvial plains
Hydro-electricity-
Health and Tourist resorts
Political boundaries- international boundaries, controversial, lost much of their significance
Defence- not completely effective, passes are used
Agriculture- terraced cultivation- valleys

17. PLATEAUS Elevated area compared to surrounding areas
Large flat top, steep cliffs, also called table land
Layered with sandstones, shales and limestones
Rivers and streams cut deep valleys and canyons in this region, changes it into a dissected plateau
Average height- 300 to 1000 m above sea level

18. Types of Plateaus Intermontane- partly or fully enclosed by mountains-
Tibet, Bolivia and Mexico
Piedmont- foot of a mountain, plain or sea on the other side
Patagonian Plateau, Appalachian Plateau, Malwa Plateau
Continental- Surrounded by seas or plains, formed due to continental uplift, quite vast
Plateaus of Brazil, South Africa, South India, Arabian Peninsula

19. Influence of Plateaus on humans
33% of earth’s surface, 9% of population
Climate- Cooler climates in Torrid Zone, high altitudes
Agriculture- Deccan Plateau, volcanic soil
Minerals- Chotanagpur plateau- coal and iron ore, Australian Plateau- gold, silver, manganeese, Brazilian Plateau- iron ore and manganese, Bolivian Plateau- tin deposits
Transport- not well developed
Hydro-electricity- rapids on rivers
Pastures- arid climates, grass grows well, Patagonia, Turkey and South African Plateaus

20. PLAINS Relatively flat and low lying surface
Some of them are rolling plains, some located at very high altitudes.
Mississippi plains- 30 m to 1500 m either side
Ganga Plains- 6 to 8 m to 200 m above sea level
Kashmir lake plain m above sea level

21. Types of Plains
Structural plains- coastal areas, upliftment of continental shelf
Erosional Plains- formed due to erosion of elevated land- Peneplains, Karst Plains, plains of glacial erosion, Desert plains
Depositional Plains- Deposition of material in lowlands, most plains in this category
Alluvial- deposition by rivers- bhabhar, bhangar, khadar
Loess- deposition by wind
Coastal- deposition by sea waves
Lava plains- thin lava, spreads wide

22. Influence of Plains on humans
Old civilizations, cradles of civilization
Agriculture- easy to irrigate, 85% of worlds agricultural produce comes from 41 % of world’s plain areas
Transport- Flat terrains, waterways also developed apart from roads and railways
Population- 90% world’s population live here, rapid pace of urbanization and industrialization
Industries- large scale growth, cheap labour, ready markets, lack mineral resources
Urbanization- favourable conditions for growth of urban areas.