Classifying Rocks Inside Earth Chapter 5 1 Pages

Classifying Rocks Inside Earth Chapter 5. 1 Pages 146 -149

Rocks • Are made of a combination of minerals and other materials. – Granite • • Quartz Feldspar, Mica Hornblende

Texture • Texture: Texture size, shape and pattern of rock grains • Grains: Grains particles of minerals or other rocks.

Texture (Grain Size) • Coarse Grained- Large and easy to see • Fine Grained- Small, hard to see with the eye.

Texture (Grain Shape) • Grains vary widely. – Tiny particles of sand – Look like seeds – Crystals – Smooth / rounded – Jagged

Texture (Grain Pattern) • Grains often form patterns. – Some lie in flat layers. – Bands of grains. – Random grains.

Texture (No Visible Grain) • Have no grain. Why? – Cool very quickly when they form, giving the rock a smooth, shiny texture like thick glass. Obsidian

Mineral Composition • Use a microscope to look at the size & shape of crystals to identify minerals in the rock • Acid test for carbonates (CO 3) in mineral composition • Magnetic Test for iron and nickel metals.

Origin • 3 Groups- refers to how the rocks formed. Igneous Sedimentary • Forms from cooling molten rock. • Magmabelow the surface. • Lava- above the surface. • Forms from particles of other rocks, remains of plants and animals that are pressed and cemented together. Metamorphic • Forms from pre-existing rock, deep underground. • Changes rock with heat, pressure and chemical reactions.

Rock Cycle Igneous Sedimentary Pressure Molten Material Metamorphic