Classifying Rocks Section 4-1 7th grade Science

Classifying Rocks When studying rocks, scientists observe the rock’s mineral composition, color, and texture

Classifying Rocks Rock Forming Minerals 20 of the minerals that make up a majority of the earths rocks

Classifying Rocks Granite a light colored rock with a high silica content Basalt a dark colored rock with a low silica content

Classifying Rocks-Texture Grains particles in rocks that give rock its texture Grain size- fine or coarse Grain shape- round or jagged Grain pattern- Banded or nonbanded

Classifying Rocks- How rocks Form There are 3 major groups of rocks

Classifying Rocks- How rocks Form Igneous Rock made from cooling Magma or Lava

Classifying Rocks- How rocks Form Sedimentary Rock  Forms when particals of other rocks and/or remains of plants and animals are pressed and cemented together Forms layers

Classifying Rocks- How rocks Form Metamorphic rock  formed or changed by heat and pressure or chemical reactions. Most forms deep underground