Rock Cycle

Why Study Rocks?

Rock Study

Mato Tipila “Bear Lodge” Paha Sapa “Black Hills” Badlands

3 Stages of Rocks  Categorized by the way they form 1. IGNEOUS 2. SEDIMENTARY 3. METAMORPHIC

Rock Cycle Sedimentary Igneous Metamorphic

Rock Cycle Simulator 602/es0602page01.cfm?chapter_no=investigation Interactive Rock Cycle Animation

Magma Gasses in Magma Silica Iron Sodium Potassium Aluminum Magnesium Water Vapor Oxygen Carbon Dioxide Nitrogen Hydrogen Sulfur Dioxide Elements in Magma 8 Basic Rock Forming Minerals Olivine Pyroxene Amphibole Orthoclase Plagioclase Muscovite Biotite Quartz

IGNEOUS ROCKS Rock-Forming Process: Lava or Magma Cooling Extrusive Cools Quickly: Plutonic Fine-Grained Crystals Intrusive Cools Slowly: Aphanitic Large-Grained Crystals

IGNEOUS ROCKS Andesite is a gray to black volcanic rock. It is generally erupted from stratovolcanoes as thick lava flows. Basalt Lava - Basalt is a hard, black volcanic rock. Basaltic lava flows quickly and which allows volcanic gases to escape without explosive events.

IGNEOUS ROCKS Obsidian is usually black in color though it can also be red or have a greenish tint. Obsidian is formed when the lava cools so quickly that crystals do not have time to grow. Obsidian fractures with very sharp edges. Native Americans use it to make knives, arrowheads, and other tools where sharp edges were important. Extrusive Granite is a common intrusive igneous rock. Because it cools slowly crystals have time to form. The name granite comes from the Latin word granum which means “a grain” for the coarse grain crystalline structure of the rock.

IGNEOUS ROCKS - TEXTURE Vesicles: Gas Pockets Glassy: No Visible Crystals Fine: Crystals < 1mm Coarse: Crystals 1-10 mm Very Coarse: Crystals > 10 mm

IGNEOUS ROCKS - COLOR Felsic 90% Light 10% Dark Mafic 90% Dark 10% Light Andesitic 50% Light 50% Dark Ultramafic Green

Igneous Rock Review What is the Rock-Forming Process?

Igneous Rock Review Rock-Forming ProcessLava or Magma Cooling

Igneous Rock Review Rock-Forming ProcessLava or Magma Cooling Two Types of Igneous Rocks?

Igneous Rock Review Rock-Forming ProcessLava or Magma Cooling Two Types of Igneous Rocks 1. Extrusive 2. Intrusive

Igneous Rock Review Rock-Forming ProcessLava or Magma Cooling Two Types of Igneous Rocks 1. Extrusive 2. Intrusive 2 Igneous Rocks?

Igneous Rock Review Rock-Forming ProcessLava or Magma Cooling Two Types of Igneous Rocks 1. Extrusive or Plutonic 2. Intrusive or Aphanitic 4 Igneous Rocks 1.Andesite 2. Basalt 3. Obsidian 4. Granite

SEDIMENTARY ROCKS Three Unique Processes Results in Three Main Groups ClasticChemical Organic

Clastic Sedimentary Rocks Rock-forming Process: Erosion & Compaction - Cementation Weathering: Wind, Rain, Moving Water, Freezing Water Breaks Rocks Into Smaller Pieces Erosion: Combination of Weathering & Movement of Sediment Sediments: The Smaller Pieces of Weathered Rocks Deposition: Sediment Settled Out of Wind, Moving Water or Due to Gravity Lithification: The Process of Sediment Changing to Rock Compaction: After sediments are deposited - The weight of the sediments squeezes the particles together. When more and more sediments are deposited on top, the weight on the sediments below increases. Cementation: Dissolved minerals fill in the spaces between the sediment particles. These liquid minerals act as glue or cement to bind the sediments together. Waterborne sediments squeeze so tightly together that most of the water is pushed out.

Clastic Sedimentary Rocks Erosion

Clastic Sedimentary Rocks

Conglomerate is made up of rounded pebbles cemented together. Breccia is made up of angular pebbles cemented together. Sandstone is sand grains cemented together into solid stone.

Siltstone is made from silt particles cemented together. Shale is made from silt particles cemented together. It is similar to siltstone but with even finer grain size.

Chemical Sedimentary Rocks Positive & Negative atoms crystallize into solid mineral crystals. This process is called precipitation. Precipitation can occur within an ocean, a lake, a cave, or where a hot spring flows out onto Earth's surface. Rock-Forming Process: Chemicals Reactions Form Minerals in Water Carbonates: Composed mainly of carbonate minerals.  Dolomite  Limestone. Dolomite

Chemical Sedimentary Rocks Evaporites: Evaporation leaves water enriched with calcium, sodium, and chlorine atoms – Which then precipitate from the water  Halite or rock salt  Gypsum Siliceous: Composed of an exceptionally high amount of crystalline siliceous material, mainly the mineral quartz  Chert

Organic Sedimentary Rocks Rock-Forming Process: Organic Matter (Plants) Coal: Lignite is black and has a crumbly consistency Bituminous coal can be dull to shiny and black.

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks?

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks Clastic ChemicalOrganic

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks Clastic ChemicalOrganic Rock-Forming Processes for each Main Group?

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks Clastic ChemicalOrganic Rock-Forming Processes for each Main Group? Erosion & Compaction - Cementation

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks Clastic ChemicalOrganic Rock-Forming Processes for each Main Group? Erosion & Compaction - Cementation Chemicals Reactions Form Minerals in Water

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks Clastic ChemicalOrganic Rock-Forming Processes for each Main Group? Erosion & Compaction - Cementation Chemicals Reactions Form Minerals in Water Organic Matter

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks ClasticChemical Organic Rock-Forming Processes for each Main Group? Erosion & Compaction - Cementation Chemicals Reactions Form Minerals in Water Organic Matter Examples from Each Main Group?

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks ClasticChemical Organic Rock-Forming Processes for each Main Group? Erosion & Compaction - Cementation Chemicals (Elements) Dissolved in Water Organic MatterConglomerate Breccia Sandstone Siltstone Shale

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks ClasticChemical Organic Rock-Forming Processes for each Main Group? Erosion & Compaction - Cementation Chemicals (Elements) Dissolved in Water Organic MatterConglomerate Breccia Sandstone Siltstone Shale Limestone Dolomite Rock Salt Gypsum Chert

Sedimentary Rock Review 3 Main Groups of Sedimentary Rocks ClasticChemical Organic Rock-Forming Processes for each Main Group? Erosion & Compaction - Cementation Chemicals (Elements) Dissolved in Water Organic MatterConglomerate Breccia Sandstone Siltstone Shale Limestone Dolomite Rock Salt Gypsum Chert Coal

Rock-Forming Process: Heat & Pressure Heat -Gravity Pulls Crust Downward -Increases Further Downward Pressure Hydrothermal Solution - Hot Steam Escapes from Mantle Carrying Dissolved Minerals - Dissolves Existing Minerals in Rocks & Deposits New Minerals - Recrystallization Alters the Rock’s Composition - Energy Source for Chemical Reactions - Mantle - Friction - Increases Further Downward

Rock-Forming Process: Heat & Pressure Contact metamorphism - Magma forces into existing rock - Heat bakes surrounding rock - Small, low-grade metamorphism Metamorphic Rock Marble: Created from limestone that has been subjected to heat

Rock-Forming Process: Heat & Pressure Regional metamorphism - Affects Large Regions -High-grade Metamorphism -Mountain-Building Black Canyon of The Gunnison Gneiss Pegmatite

Foliated Non-foliated Bands or Layers Progressing Through Stages of Metamorphism One Mineral Two Main Groups

Shale Slate Schist Gneiss

Shale, Mudstone, Siltstone (Very Fine Grained) Slate (Fine Grained) Schist (Medium – Coarse Grained) Granite, Igneous Rocks Gneiss (Medium – Coarse Grained) Textures

Limestone Marble (Medium – Coarse Grained) Quartz Sandstone Quartzite (Medium – Coarse Grained)

What are the 2 groups?

Foliated Non-Foliated

What are the 2 groups? Foliated Non-Foliated What are the foliated stages?

What are the 2 groups? Foliated Non-Foliated What are the foliated stages? Shale – Slate – Schist – Gneiss

What are the 2 groups? Foliated Non-Foliated What are the foliated stages? Shale – Slate – Schist – Gneiss What are the Non-Foliated rocks & why are they non-foliated?

What are the 2 groups? Foliated Non-Foliated What are the foliated stages? Shale – Slate – Schist – Gneiss What are the Non-Foliated rocks & why are they non-foliated? Marble & Quartzite – They are composed of single minerals

Rock Cycle Sedimentary Igneous Metamorphic

Rock Reflection Mato Tipila “Bear Lodge” Paha Sapa “Black Hills” Igneous Rock - Intrusive Sedimentary – Limestone Metamorphic - Granite Sedimentary – Deposition & Erosions Fossils of Extinct Mammals Metamorphic - Shale Badlands

References