Structure and Processes of the Lithosphere

Structure and Processes of the Lithosphere

Mr. Mendoza

The Rock Cycle

What is a Rock?

Any solid mass of mineral or mineral-like matter that occurs naturally as part of our planet

3 types:

Igneous

Sedimentary

Metamorphic

The Rock Cycle

Interactions among Earth’s water, air, land, and living things can cause rocks to change from one type to another

A continuous process

Igneous Rocks

Forms when lava or magma hardens

Lava Molten rock on the surface of the Earth

Magma Molten rock beneath Earth’s surface

Igneous Rocks are formed by

Cooling 

Crystallization

Formation of Igneous Rocks

Intrusive Igneous Rock: forms when magma hardens beneath Earth’s surface Ex: Granite

Extrusive Igneous Rock: forms when lava hardens on the surface of the Earth Ex: Rhyolite

Classification of Igneous Rocks

Texture and composition are two characteristics used to classify igneous rocks

Multiple Choice

This rock started as molten magma. What type of rock is this?

• Sedimentary
• Igneous
• Metamorphic

Multiple Choice

Which rock is formed form the cooling of volcanic ash on Earth's surface?

• intrusive igneous

• foliated metamorphic

• extrusive igneous

• organic sedimentary

What is a Sedimentary Rock?

Forms when existing rocks are broken down into sediment then compacted and cemented together

Processes

Cementing 

Compaction

Formation of Sedimentary Rocks

Weathering: Any process that break rocks into sediments

Erosion : The removal of weathered rocks

Deposition: when an agent of erosion (water, wind, ice, or gravity) loses energy, it drops the sediment

Formation of Sedimentary Rocks

Compaction: is a process that squeezes or compacts sediments together

Cementation:  takes place when dissolved minerals are deposited in the tiny spaces among the sediments

Multiple Choice

A rock formed from fragments of other rocks is a(n)

• Metamorphic Rock
• Sedimentary Rock
• Extrusive Rock
• Igneous Rock

What is a Metamorphic Rock

Form when existing rocks are changed by heat and pressure Metamorphism: means “change form”

Agents of Metamorphism

Heat: provides the energy needed to drive chemical reactions which causes existing minerals to recrystallize

Agents of Metamorphism

Pressure: applied in all directions on a rock which causes spaces between mineral grains to close

Agents of Metamorphism

Hydrothermal Solutions: hot, water based solutions that promote recrystallization by dissolving original minerals and then depositing new ones

Classification of Metamorphic Rocks

Classified by texture and composition

Foliated: Rock with layered or banded appearance Ex:  Gneiss

Non-foliated: No layered or banded appearance Contains only one mineral Ex:  Marble

Multiple Choice

This rock was another type of rock that was heated and compressed over time. What type of rock is this?

• Sedimentary
• Igneous
• Metamorphic

Multiple Choice

What are the 3 major types of rocks?

• Igneous, Metamorphic, Sedimentary
• Metamorphic, Igneous, Cementation
• magma, lava, crystals