7/27/2019 Chapter 2 Rock Identification

1/20

7/27/2019 Chapter 2 Rock Identification

2/20

Identification of Rock

To classify the rock, we must considered:

Origin

Composition

Texture

7/27/2019 Chapter 2 Rock Identification

3/20

Rock Origin

Categorized into 3 main groups of rock:

Igneous

SedimentaryMetamorphic

Not in the category: Meteorite.

7/27/2019 Chapter 2 Rock Identification

4/20

Rock Cycle

7/27/2019 Chapter 2 Rock Identification

5/20

Igneous Rock

Rock forming process:

Form by Crystallization of molten rock /

magma.

Sub group:

Plutonic: Form at significant depth belowthe surface.

Volcanic: Formed at or near the surface.

7/27/2019 Chapter 2 Rock Identification

6/20

Igneous Rock

7/27/2019 Chapter 2 Rock Identification

7/20

Igneous Rock

Plutonic / Intrusive:

Slow cooling process

Coarse grain size (Phaneritic): > 1mm

Volcanic / Extrusive:

Fast cooling process

Fine grain size (Aphanitic):

7/27/2019 Chapter 2 Rock Identification

8/20

Igneous Rock

Texture:

i. Pegmatitic

ii. Phaneritic

iii. Aphanitic

iv. Porphyritic

v. Vesicularvi. Glassy

vii. Pyroclastic

7/27/2019 Chapter 2 Rock Identification

9/20

Igneous Rock

Composition:

i. Felsic

ii. Intermediate

iii. Mafic

iv. Ultramafic

7/27/2019 Chapter 2 Rock Identification

10/20

Igneous Rock

7/27/2019 Chapter 2 Rock Identification

11/20

Igneous Rock

7/27/2019 Chapter 2 Rock Identification

12/20

Igneous Rock

Photo from Agus K Supono, RRI homepage

7/27/2019 Chapter 2 Rock Identification

13/20

Sedimentary Rock

Rock forming process:

Form from pre-existing rock particles.

Rock(weathering)small particles

(transportation)(deposition)

(lithification by compaction and

cementation)SEDIMENTARY ROCK

7/27/2019 Chapter 2 Rock Identification

14/20

Sedimentary Rock

Sub group and texture:

Clastic: Gravel, Sand, Silt and Clay

Chemical: Gypsum, Quartz and Calcite

Biologic: Calcite, Carbon and Fossils.

Subgroup Texture

Clastic Gravel SiltSand Clay

Chemical Quartz Gypsum

Bio-chemical Calcite

Biologic Fossils Carbon

7/27/2019 Chapter 2 Rock Identification

15/20

Sedimentary Rock

7/27/2019 Chapter 2 Rock Identification

16/20

Sedimentary Rock

Grand Canyon photo by Reiner Stenzel

7/27/2019 Chapter 2 Rock Identification

17/20

Metamorphic Rock

Rock forming process:

Form by re-crystallization of the rocks by

the action of pressure, temperatures and

pore fluids (chemistry).

Sub group and texture:

Regional: Foliated

Contact: Non-foliated

Dynamic: Non-foliated

7/27/2019 Chapter 2 Rock Identification

18/20

Metamorphic Rock

Subgroup Texture

Regional Foliated

slaty

Phyllitic

Schistosity

Gneiss Banding

7/27/2019 Chapter 2 Rock Identification

19/20

Type of RockRock Forming

ProcessSubgroup Texture Composition Mineralogy Parent Rock Index Mineral

Igneous

Crystallization of

the molten

rock/magma

Intrusive/

Plutonic Course grain

Pegmatite

Felsic

Intermediate

Mafic

Ultramafic

Refer to

Bowen seriesx x

Pheneritic

Porphyritic

Extrusive/

VolcanicFine grain

Aphanitic

Vesicular

Glassy

Pyroclastic

Sedimentary

weathering,

transportation,

deposition and

lithification of

the rock

particles

ClasticGravel Silt

What mineral you see inside x x

Sand Clay

Chemical Quartz Gypsum

CalciteBiologic

Fossils Carbon

Metamorphic

Recrystallization

of the rock by

the action of

pressure and

temperature

Regional Foliated

slaty

What mineral you see inside

Phyllitic

Schistosity

Gneiss

Banding

ContactNon-Foliated x

Dynamic

7/27/2019 Chapter 2 Rock Identification

20/20

Thank you