Endogenic and Exogenic Processes

1. GEOLOGIC PROCESSES ON
EARTH

2. EXOGENOUS PROCESSES
• Occur on or near the surface of
Earth
• Usually influenced or driven by
gravity, water, wind and
organisms
• In extreme cases, it can wipe out
majority of the organisms
inhabiting that area.

3. WEATHERING
• The disintegration of rocks, soil
and minerals together with other
materials through contact with
Earth’s subsystems
• Happens even without
movement or transportation

4. Physical Weathering
• Breakdown of rocks by mechanical
forces concentrated along rock
fractures
• Can occur due to changes in
temperature and pressure
• Example : soil cracks because of
extreme heat or drought
• In some cases, water, wind or ice may
scrape rocks or soil

5. Chemical Weathering
• Rocks break down by chemical reactions
• New or secondary minerals develop and
sometimes replace the original properties
of the minerals in the original rock or soil
• CONTRIBUTORS:
• OXIDATION – reaction of a substance with
oxygen
• HYDROLYSIS – the chemical breakdown of
a substance when combined with water
• ACID RAIN – may cause metals and stones
to corrode or deteriorate and change their
properties

6. EROSION
• Process by which earth’s surface is worn
away by wind, water, or ice
• Moves rock debris or soil from one place to
another
• Takes place when there is rainfall, surface
runoff, flowing rivers, seawater intrusion,
flooding, freeing and thawing, hurricanes,
wind, etc.
• Movement of land animals during migration
or stampede
• Human activities: deforestation, overgrazing
and mining

7. MASS WASTING
• Movement of large masses of materials
(rock debris, soil, mud) down a slope or
a steep sided hill or mountain due to
the pull of gravity
• Very destructive in areas with increased
water flow.
• DEBRIS FLOW
• MUDFLOW
• SLUMP

8. Mudflow
• Happens when combined soil and
water flow down a slope
• Usually happens near rivers or
streams where soil or sand is always
moist or has been soaked in water
for a long time.

9. Debris flow
Happens when a large amount of
sediments, usually rocks of various
sizes, falls down the slope.
Does not need water to flow down

10. Slump
• Slow movement of soil along a
curved surface.
• In time, the area would look curved
because of the depression formed by
the sinking land

11. SEDIMENTATION
• Accumulation of materials such as
soil, rock fragments and soil particles
settling on the ground.
• Usually occurs in streams or sea
erosion
• Over time, the sediment load
becomes thick and forms a new layer
of ground

13. • If geologic processes seem
to bring risk to human
safety, where then is a safe
place to live? Is there even
any?

14. ENDOGENOUS PROCESSES
• Takes place within or in the interior
of Earth.
• The driving force is the thermal
energy of the mantle.
• Responsible for earthquakes,
development of continents, mountain
building, volcanic activities, etc.

15. MAGMATISM
• Magma is the original material that
make up igneous rocks.
• Magmatism happens when a
magma is generated and develops
into igneous (magmatic) rocks
• The process can take place either
under the surface or on the surface
of Earth.

16. VOLCANISM (PLUTONISM)
• Process that usually happens after
the magma is formed.
• Magma tries to escape from the
source through openings such as
volcanoes or existing cracks on the
ground.
• As soon as magma reaches the
surface of the earth it is now called
lava.

17. METAMORPHISM
• Process of changing the materials that
make up a rock.
• Chemical components and geologic
characteristics of the rock changed due
to heat and pressure that are
increasing or decreasing.
• Note:
• Rocks changing due to weathering and
sedimentation are not considered to
have undergone metamorphism.

18. • What drives the endogenous
processes on Earth?
• Where does the force come
from?
• Why is it called
endogenous?