Learning Targets 1.I can ID and explain the processes of the rock cycle. 2.I can trace the path of minerals through the rock cycle. 3.I can ID differentiate between the 3 types of rocks. 4.I can compare and contrast the 2 types of igneous rocks. 5.I can differentiate between the types of sedimentary rocks. 6.I can ID and differentiate between the types of metamorphic rocks.

Chapter 3 - Rocks What can be learned by studying rocks? We can learn more about earth(history, resources, how it formed, etc.) So what is a rock? Rock = is a mixture of 1 or more minerals.

The Rock Cycle Continuous model that shows how rocks can change from 1 type into another. Interactions among water, air, land, and living things can cause rocks to change. Two types of energy that drive the rock cycle: 1. SUN = external forces = weathering, etc. produce sedimentary rocks 2. MAGMA = internal forces = heat produces igneous and metamorphic rocks

and deposition and chemicals Heat, pressure, and chemicals and crystallization

Rock Cycle Driving Factors 1.Sun - Drives the water cycle that produces weathering and erosion. 2.Heat from Earth’s Interior -Heat produces igneous and metamorphic rocks. 3.Gravitational Energy - Gravity pulls everything down…rockslides, falling rain, tall mountains, etc.

Vocab. terms Magma – underground molten rock Lava – above ground molten rock Crystallization – formation of minerals from cooling magma/lava Weathering – breaking rocks into smaller pieces called (sediments)

Erosion – transportation of sediments Deposition – dropping off of sediments Lithification – compacting and cementing of sediment (turn to rock) Metamorphism – changing one type of rock into another (3 ways: heat/pressure/or chemicals)

Igneous Rocks (from fire) 2 main types 1. Intrusive Cools and forms slowly (large crystals) From magma Underground 2. Extrusive Cools and forms quickly (small crystals) From lava Above ground

Igneous Rocks Classification 2 ways to classify igneous rocks 1. Texture & 2. Composition –Texture (4 types) 1. Coarse grained – slow cooling, large crystals 2. Fine grained – fast cooling, small crystals 3. Glassy – super fast cooling, glassy 4. Porphyritic – slow and fast cooling, has both large and small crystals

Course-Grained Igneous Texture

Fine-Grained Igneous Texture

Obsidian Exhibits a Glassy Texture.

Porphyritic Igneous Texture

4 Magma Groups (families) 1. Granitic (felsic) = continental High in silica, light colored, low density 2. Basaltic (mafic) = oceanic Low in silica, dark colored, high density 3. Andesitic (intermediate)

Sedimentary Rocks Your teacher rocks!

Sedimentary Rocks From (Latin) sedimentum = settling Made from sediments 4 agents of erosion (transportation) 1.Water (largest) 2.Wind (W W G G) 3.Glaciers 4.Gravity

Sedimentary Rock Classification 3 MAIN TYPES: 1. Clastic = form from sediment 2. Chemical = form from precipitation or evaporation 3. Biochemical (organic) = form from remains of once living organisms

Clastic Sedimentary Rocks categorized by size/shape Conglomerate – rounded pebble sized Breccia – angular pebble sized Sandstone – sand sized Siltstone– silt sized Shale/mudstone – clay sized

Chemical Sedimentary Rocks Crystalline limestone – precipitates from ocean water Travertine – precipitates in caves Chert/flint – quartz (more info) Gypsum – precipitates from oceans, too Rock salt – evaporated salt water

Biochemical Sedimentary Rocks Fossil limestone – fossils remains Coquina – shells and shell fragments Chalk – microscopic shells and clay Bituminous coal – plant remains

Sedimentary Rock Features Ripple Marks Mudcracks Bedding Tilted Bedding Cross-Bedding Graded Bedding

Metamorphic Rocks Means to change form 2 types of metamorphism 1. Contact Metamorphism – small areas from magma 2. Regional Metamorphism – large areas from mountain building

3 Agents of Metamorphism 1.Heat (temperature) 2.Pressure (stress) 3.Chemicals

Metamorphic Rock Types 1.Foliated – easily seen layers due to heat and pressure. ex: gneiss and slate 2.Non foliated – no layers can be seen ex: marble and quartzite

1. Foliated Metamorphic 1.Slate – very thin layers, from shale 2.Phyllite – thin layers, sheen, wavy, from slate 3.Schist – medium layers,shiny, micas, from phyllite 4.Gneiss – distinct black & white layers, from schist or granite

Nonfoliated Metamorphic 1.Marble – shiny, fizzes in acid, H = 3, from limestone 2.Quartzite – shiny, won’t fizz, H = 6 – 7, from sandstone 3.Anthracite coal – shiny, black, from bituminous coal The carbon cycle…see page 85

Lab Information

Igneous Rocks = most common overall --never layered --can be spotty,glassy --can have holes --crystals rectangular

Sedimentary Rocks Most common on surface Usually dull earthy colors Can have fossils Can be layered Rounded grains

Metamorphic Rocks = most common around here gneiss & schist crystals flattened may be layered/foliated can be shiny/sheeny