1. CLASSIFICATION
OF ROCKS
1
Classify rocks into igneous, sedimentary, and metamorphic.

2. 2
GemsMinerals

3. ROCKS
• any naturally occurring solid mass or aggregate of minerals
or mineraloid matter.
• categorized by the minerals included, its chemical
composition and the way in which it is formed.
3
Kapurpurawan Rock Formation Stonehenge in England A Boulder

4. 4
Nakabuang Arc, Sabtang Island, Batanes

5. 5
Kapurpurawan Rock Formations, Burgos,
Ilocos Norte

6. 6

7. 7

8. 8
Zaragosa Rock Formation (Surigao, Mindanao)

9. 3 Main Categories of Rocks 9
IGNEOUS SEDIMENTARY METAMORPHIC
“ignis” – fire
Sediment – materials
deposited by water, wind and/or
glaciers
“meta” – change
“morph” - form

10. 103 Main Categories of Rocks

11. 11ROCK CYCLE
The transformational processes that change
rocks from one kind to another.

12. 12

13. 13IGNEOUS ROCKS
• from a Latin word
“ignis” which means
fire.
• The parent material of
igneous rocks is usually
magma (a molten material
from deep within the earth
that cools and hardens).

14. 14IGNEOUS ROCKS
1) Fine-grained Igneous rock
(“Aphanitic”) - has smaller crystal
due to the faster rate of cooling of
the magma.
2) Coarse-grained Igneous Rock
(“Phaneritic”) - has larger crystal
due to the slower rate of cooling of
the magma.
Types based on Texture:

15. 15IGNEOUS ROCKS
Types based on Texture:
Fine-grained Igneous rock
(“Aphanitic”)
Coarse-grained Igneous Rock
(“Phaneritic”)

16. 16IGNEOUS ROCKS
1) Mafic – are
magmas associated
with crystal
spreading.
2) Felsic – are
magmas associated
with crystal
compression.
Types based on Composition:

17. 17IGNEOUS ROCKS
1) INTRUSIVE IGNEOUS ROCKS
✓ cool slowly
✓ forms coarse grained rock
✓ presence of crystal growth
2) EXTRUSIVE IGNEOUS ROCKS
✓ cool quickly
✓ forms fine-grained rock
✓ lack of crystal growth
General Types:

18. 18IGNEOUS ROCKS
General Types:

19. 19IGNEOUS ROCKS
Examples of Igneous Intrusive
or Plutonic Igneous Rocks:
Granite Gabbro Diorite

20. 20IGNEOUS ROCKS
Examples of Igneous
Extrusive or Volcanic Igneous
Basalt Obsidian Pumice

21. 21SEDIMENTARY ROCKS
• formed by the compaction and cementing
together of sediments (broken pieces of rock-like
gravel, sand, silt, or clay)

22. 22SEDIMENTARY ROCKS
Importance Processes Involved:
• Lithification - a process of sementing soft,
unconsolidated sendiments into hard rocks.
• Deposition - process when rocks are
fragmented into tiny bits, then carried to low
areas and settled at the bottom.
• Sedimentation - process of building up of
deposited rocks after many years.

23. 23SEDIMENTARY ROCKS
Stages in the Formation of Sedimentary Rocks

24. 24SEDIMENTARY ROCKS
Three (3) Main Types:
1. Clastic- are formed from mechanical
weathering debris.
2. Chemical – are formed when dissolved
materials precipitate from solution.
3. Organic – are formed by accumulated
sedimentary debris caused by organic
processes.

25. 25SEDIMENTARY ROCKS
Three (3) Main Types:
TYPE EXAMPLES
CLASTIC
• Conglomerate – composed of pieces
pebble-size or larger
• Sandstone - composed of sand-size pieces
• Shale - composed of pieces smaller than
fine sand
CHEMICAL
• Limestone – a whitish or grayish rock made
of the mineral calcite.
• Rock salt, iron ore, chert, flint, some
dolomites, and more.
ORGANIC
• coal, lignite, oil shale, or black shale
• Chalk
• Limestone with fossils
• Coquina

26. 26METAMORPHIC ROCKS
• The metamorphic rocks get
their name from “meta”
(changed) and “morph”
(form).
• Movement of earth causes
rock to be pressed or buried
that leads to an increase in
temperature and pressure.

27. 27METAMORPHIC ROCKS
Metamorphism is the transformation of the
rock’s minerology and physical characteristics.

28. 28METAMORPHIC ROCKS
Metamorphism is the transformation of the
rock’s minerology and physical characteristics.

29. 29
Types of Metamorphism
1) CONTACT (THERMAL) Metamorphism
✓ evolves when rock near igneous intrusive
gets heated.
✓ produces non-foliated metamorphic
rocks.
2) REGIONAL (PRESSURE) Metamorphism
✓ affects a large area due to mountain
formation.
✓ foliated rocks are produced and strong
pressure effects.
METAMORPHIC ROCKS

30. 30
Two (2) Main Types:
1) NON-FOLIATED
✓ formed around the igneous intrusive.
✓ their atoms recognize while becoming more compact
and dense.
✓ shows color bands that reflects very small impurities.
2) FOLIATED
✓ formed within the earth’s interior.
✓ extremely high temperature and unequal pressure.
✓ better identified on the basis of their texture.
METAMORPHIC ROCKS

31. 31
Two (2) Main Types:
METAMORPHIC ROCKS
• Marble - derived from limestone-its parent rock. A
hard crystalline rock and the most beautiful rock
because of its shimmering luster.
• Quartzite - derived from sandstone, its hard
and durable.
• Slate – derived from shale.
• Serpentine – originates from basalt.
• Gneiss – derived from conglomerate.
Contains feldspar or quartz.

32. 32
Examples:
METAMORPHIC ROCKS

33. 33METAMORPHIC ROCKS
PROTOLITH
- the original / parent rock or the unmetamorphosed rock
from which a given metamorphic rock is formed
- From the Greek words:
“proto” means first and “lithos” means rock

34. 34METAMORPHIC ROCKS
PROTOLITH

35. 35TYPES OF ROCKS