Geologic Processes on Earth ( Exogenic & Endogenic)

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1. Geologic Processes on Earth Exogenic Processes Endogenic Processes

2. Exogenic Processes -i t is formed or occuring on the surface of Earth ⟶ these processes are carried through by Geomorphic Agents: gravity, flowing water (rivers), moving ice (glaciers), waves and tides (oceans and lakes), wind, plants, organisms, animals and humans.

3. Types of Exogenic Processes a. Weathering b. Mass Wasting c. Erosion and Transportation d. Sedimentation

4. Weathering It is the process of disintegration and decomposition of rocks There are three types of weathering: Physical or Mechanical Weathering Chemical Weathering Biological Weathering

5. Physical or Mechanical Weathering the breakdown of rocks into pieces without any change in it’s composition. the size and shape of the rocks may change and this occur because of different factors. Types of Weathering

6. Factors Affecting Physical Weathering PRESSURE due to tectonic forces, granite may rise to form mountain range. After the granite ascends and cools, the overlaying rocks and sediments may erode. At the point when the pressure diminishes, the rock expands, cools and became brittle and fractured.

7. Factors Affecting Physical Weathering TEMPERATURE rocks expand and are fractured when expose to high temperature. However, if the temperature drops to zero degree celsius (freezing point of water), it also expands and causes fracture.

8. Factors Affecting Physical Weathering FROST WEDGING generally, rocks have fracture in its surface and when water accumulates in the crack and at that point freezes, the ice expands and break the rock apart.

9. Factors Affecting Physical Weathering ABRASION the breakdown of rocks is the caused by impact and friction. This primarily occurs during collision of rocks, sand, and silt due to current or waves along a stream or seashore causing sharp edges and corners to wear off and became rounded.

10. Factors Affecting Physical Weathering ORGANIC ACTIVITY the roots grow causing penetration into the crack, expand and in the long run, break the rock.

11. Factors Affecting Physical Weathering HUMAN ACTIVITY the activities such as digging, quarrying, denuding forests and cultivating land contribute to physical weathering.

12. Factors Affecting Physical Weathering BURROWING ANIMALS animals like rats, rabbits and squirrels excavate into the ground to create a space for habitation.

13. Chemical Weathering the changes in the composition of rocks due to the chemical reactions below: dissolution hydrolysis oxidation Types of Weathering

14. Chemical Reactions Affecting Chemical Weathering DISSOLUTION it occurs in specific minerals which are dissolved in water. the formation of stalactites and stalagmites in caves are brought about by this chemical reactions.

15. HYDROLYSIS the rock-forming minerals like amphibole, pyroxene, and feldspar react with water and form different kinds of clay minerals. Chemical Reactions Affecting Chemical Weathering

16. OXIDATION the response of oxygen with minerals. if the iron oxidizes, the mineral in rock descomposes. rusting is an example of this chemical reaction. Chemical Reactions Affecting Chemical Weathering

17. the important process in the formation of soil. Soil is a mixture of grains, organic matter, , and gas. Weathering  

18. Erosion the separation and removal of weathered rocks due to different agents like water, wind, and glacier that causes transportation of the material to where they are deposited. Plants, animals, and humans play an important role in the erosional process.

19. the movement of sediments downslope under the influence of gravity. examples are fall, slide, avalanche, and flow. Mass Wasting

20. the process in which the weathered materials carried out by erosion settle down in a particular location. Deposition