Rock Classification Rocks are divided into three main

Composition chemical make up of the rock or what it is made of. n

Texture/Grains n Determined by the grains size, shape and position. n Igneous can be

Texture/Grains n. Metamorphic textures consist of two main types: foliated and non-foliated textures. n.

What are they? n Rock made from cooled –LAVA, above ground or –MAGMA, below

Classification They are classified in 3 ways: 1. Texture – Grain/ minerals 2. Origin

Texture/Grain n Coarse Grained = large grains, cooled slowly Think about it…. If it

Igneous Rock Formation-Origin n Extrusive – formed ABOVE GROUND. It cools fast so it

Examples of each type of ROCK Fine Grained Basalt = Extrusive Igneous rock Course

Mineral Composition n How much silica is in the magma/lava? – Low silica content

Draw pictures of the different types of Igneous Rocks! Small or No Crystals Big

Ticket out: CHOOSE ONLY ONE What makes up the grains in an igneous rock?

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Rock Classification Rocks are divided into three main classes based on how they form: 1. Igneous 2. Sedimentary 3. Metamorphic Each type of rock can be further classified based on: n Composition and texture

Composition chemical make up of the rock or what it is made of. n The n This can be minerals or other materials: shells, clay, plants, sand, pebbles

Texture/Grains n Determined by the grains size, shape and position. n Igneous can be fine or coarse grain n Sedimentary can be characterized by observing lithified (cemented) inorganic grains, minerals, organic material, or fossil fragments. The wide range of textures common in sedimentary rocks is separated into clastic, chemical, and bioclastic (biochemical) groups.

Texture/Grains n. Metamorphic textures consist of two main types: foliated and non-foliated textures. n. Texture can reveal the process that formed the rock.

Igneous Rocks

What are they? n Rock made from cooled –LAVA, above ground or –MAGMA, below ground.

Classification They are classified in 3 ways: 1. Texture – Grain/ minerals 2. Origin - where formed 3. Mineral Composition – made from

Grain Size Have…. SPECIAL NAMES

Texture/Grain n Coarse Grained = large grains, cooled slowly Think about it…. If it cools over a long time – the grains have time to get big! Most abundant intrusive rock is GRANITE n Fine Grained = small grains, cooled fast Think about it… If it cools over a short time – the grains don’t have time to get big! Example: Basalt

Igneous Rock Formation-Origin n Extrusive – formed ABOVE GROUND. It cools fast so it has small grains. n Intrusive – formed UNDERGROUND. It cools slowly so it will have large grains. Laccolith

Examples of each type of ROCK Fine Grained Basalt = Extrusive Igneous rock Course Grained Granite = Intrusive Igneous rock

Mineral Composition n How much silica is in the magma/lava? – Low silica content = dark colored = Mafic – High silica content = light colored = Felsic High Silica Content Felsic Igneous Rock Low Silica Content Mafic Igneous Rock

Draw pictures of the different types of Igneous Rocks! Small or No Crystals Big Crystals Lighter Darker

Label the igneous rock formation

Ticket out: CHOOSE ONLY ONE What makes up the grains in an igneous rock? n. Illustrate grains of an igneous rock and explain why this happens n. Compare and contrast intrusive and extrusive igneous n