The Rock CycleThinking about relationships among the major rock groups

2

Major Rock Groups Igneous

Formed from a melt (molten rock) Plutonic (intrusive):slow cooling and

crystallization Volcanic (extrusion): quick cooling at the surface

Sedimentary Formed at the Earth’s surface Clastic (Mineral Fragments or grains, clays) Chemical (crystalline chemical/biochemical

precipitates) Metamorphic

Changed by pressure, temperature and fluids.

Fig. 2.9

MAGMA

4

MAGMA

Crystallization

IGNEOUS

5

MAGMA

IGNEOUS

Plutonic

Crystallization

6

MAGMA

Volcanic

IGNEOUS

Plutonic

Crystallization

7

MAGMA

Volcanic

IGNEOUS

Plutonic

Uplift

Crystallization

Weathering

8

MAGMA

Volcanic

IGNEOUS

Plutonic

SEDIMENT

Uplift

Crystallization

Weathering SEDIMENT

9

MAGMA

Volcanic

IGNEOUS

Plutonic

SEDIMENT

SEDIMENTARY

Uplift

Crystallization

WeatheringErosion

Transport

Deposition

10

MAGMA

Volcanic

IGNEOUS

Plutonic

SEDIMENT

SEDIMENTARY

Uplift

Crystallization

WeatheringErosion

Transport

Deposition

11

MAGMA

Volcanic

IGNEOUS

Plutonic

SEDIMENT

SEDIMENTARY

METAMORPHIC

UpliftBurial

Increased P&T

Crystallization

WeatheringErosion

Transport

Deposition

12

MAGMA

Volcanic

IGNEOUS

Plutonic

SEDIMENT

SEDIMENTARY

METAMORPHIC

UpliftBurial

Increased P&T

MeltingCrystallization

WeatheringErosion

Transport

DepositionCan you see

any shortcuts?

13

MAGMA

Volcanic

IGNEOUS

Plutonic

SEDIMENT

SEDIMENTARY

METAMORPHIC

UpliftBurial

Increased P&T

MeltingCrystallization

WeatheringErosion

Transport

Deposition

The rock cycle demonstrates the relationships among the three major rock groups

It is powered by the interior heat of the Earth

As well as earth’s momentum and…

The energy from the sun It involves processes on

the Earth’s surface as well as the Earth’s interior

It connects the “hydrologic cycle” with the “tectonic cycle”.

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What is a mineral? Naturally occurring Non-organic Characteristic chemical

composition Distinctive physical properties Crystalline structure

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Mineral properties Color Luster Habit (Shape) Cleavage & Fracture Streak Hardness Other

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Color: Not mineral specific

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Luster: How minerals reflect light

Non-metallic

Metallic

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Mineral Habit (Shape)

Shape a mineral takes if grown unimpeded

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Cleavage & FractureCleavage: planes of

weakness along which minerals can break

Fracture: surfaces along which minerals can break

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Cleavage & Fracture

Best identified on a fracture surface

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Streak:

The powdered form of a mineral

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Hardness:Based on Moh’s scale of hardness

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Other Properties Specific gravity Reaction to acid Striations Magnetism

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Igneous Rocks

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Metamorphic Rocks

GneissSchist

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Sedimentary Rocks

Shale

Conglomerate

Sandstone