JOURNAL

Can oil and natural gas be classified as minerals? Justify your answer with

information from your notes.

Rocks, Rocks, and more Rocks!!!!

What is a rock?

•A solid mixture of crystals of one or more minerals.

What’s so great about rocks?

• Used to make tools & weapons– Spears & arrow heads– Obsidian scalpels used in delicate

operations

• Used to make structures (new & old)

• Some contain fossils which help scientists learn about the past.

A. The Rock Cycle A. The Rock Cycle

• The process by which one rock type changes into another.

• The rock cycle takes millions of years.

3 processes that change one rock type to another.

1. Weathering & Erosion

2. Heat & Pressure

3. Melting & Cooling

3 Types of Rocks1. Igneous Rock-formed by melting and cooling

2. Sedimentary Rock-formed by weathering and erosion

3. Metamorphic Rock-formed by heat and pressure

Rocks are classified based on how they were formed

B. Igneous Rock1. Igneous is Latin for “fire”2. Igneous rock forms from cooling lava

and magma.a. Lava is molten rock that flows on the

Earth’s surfaceb. Magma is molten rock found below the

Earth’s surface

3. Igneous rocks make up most of the rocks on Earth used for building materials because they are very hard and last a long time

Examples of Igneous Rocks

Obsidian

Granite

Rhyolite

Gabrro

Pumice

C. Sedimentary Rock1. Sediments = rock fragments caused by erosion

which is the breakdown of rock by wind, water, ice or gravity (agents of erosion) and weathering

a. Most are formed underwaterb. Texture is uneven. Why do you think this

happens?

1. Most fossils are found here. Fossils would burn up in other rock processes but sedimentary rocks preserve once-living remains

70% of all rocks on Earth

D. Metamorphic Rock

– Meta means “changed”– Morphos means “shape”

• The structure, texture, or composition of the rock has changed by pressure, heat, or the combination of both.