This document summarizes different geological processes including rock formation, weathering, material movement, erosion, and the impact of past glaciations. It describes three main rock types - igneous, sedimentary, and metamorphic - and the processes of mechanical and chemical weathering that break rocks into smaller pieces. Material is moved via mass movement, glaciers, rivers, and other processes. Coastal, water, ice, and wind erosion shape the landscape over time. Past glaciations left behind features like moraines and U-shaped valleys while influencing water supply and transportation routes.

1. The Force of Geology-Part Three
Endogenic and Exogenic Process
Widodo, S.T., M.T.
Mining Geology SMK N 1 Balikpapan
Weathering, Material Movement & Erosion

2. Rock Formation
 Igneous
 Cooled molten crustal material (magma)
 E.g. Basalt, granite
 Sedimentary
 Sediments laid down in layers and from high pressure
 E.g. Sandstone, shale, limestone
 Metamorphic
 The 2 rocks above can be later compacted again, by
heat & pressure, and so undergo further change
 E.g. Marble derived from limestone

3. Weathering
 Process of breaking rock into pieces
 The first step in the formation of soil
 Mechanical weathering
 Process of rocks breaking down by physical force, e.g. tree
roots, freezing & thawing - pot holes. See next slide.
 Chemical weathering
 Process of breaking down rock by:
 Exposure to air and water
 Acids released by decaying vegetation
 Oxidation (rust due to iron content)
 Leaching (nutrients being washed downwards beyond plant
roots)
 Decomposition of calcium carbonate

4. Mechanical
 Frost Wedging: the most important type of mechanical weathering;
freeze-thaw repetition. Also responsible for city pot-holes.
 Personal home experiment

6. Frost Wedging

7. Frost Heaving

8. Plant Root

9. Friction & Repeated Impact

10. Burrowing of Animals

11. Temperature Changes

12. Chemical
 Water weathers rock by dissolving it

13. Oxygen
 Iron combines with oxygen
in the presence of water in
a processes called
oxidation
 The product of oxidation is
rust

14. Living Organisms
 Lichens that grow on rocks produce weak
acids that chemically weather rock

15. Acid Rain
 Compounds from burning coal, oil and gas
react chemically with water forming acids.
 Acid rain causes very rapid chemical
weathering

16. Karst Topography
 A type of landscape in rainy regions where
there is limestone near the surface,
characterized by caves, sinkholes, and
disappearing streams.
 Created by chemical weathering of limestone

17. Features of Karst: Sinkholes

18. Features of Karst: Cave

19. Movement of Weathered Material
 Mass movement could be:
 Slow gradual movement occurring near the surface, like
soil creep
 Or in dramatic movements such as rock slides, landslides
and mudflows

21. Glaciers
 Slow moving “rivers of ice” flowing from colder to
warmer regions. They move only a few feet per year.
 They act like conveyor belts, picking up sediment and
dropping it in depositional areas
 These glacial sediments are called, Moraines
 Terminal moraines – found at the very end of
glacier
 Lateral moraines – found along the sides
 Medial moraines – found in the middle
 See next slide

22. Moraines

24. Impact of Past Glaciations
 Soils & Landforms
 Advance and retreat of glaciers leave behind highly
fertile soil and various landforms (see next slide).
 Water supply & Transportation routes
 Retreating glaciers left sand and gravel deposits
yielding large supplies of ground water
 Also, water transport is heavily influenced by
glacial melt water channels left behind by receding
glaciers. E.g. Great Lakes, Hudson Bay, etc. See
pg 117.

25. U-shaped valleys
& jagged/rugged
landscapes

27. Erosion
 The process by which water, ice, wind or
gravity moves fragments of rock and soil.

29. Coastal Erosion
 Longshore currents:
 Currents traveling parallel to the shore, caused by
repeated breaking of waves. Capable of carrying
enormous amounts of sediment, and changing the form
of beaches.

30. Coastal Erosion
Effects of longshore currents:

31. Water Erosion
 Rivers, streams, and runoff

32. Ice Erosion
 Glaciers

33. Wind Erosion