CHAPTER Rocks 6.1 How Rocks Form 6.2 Igneous Rocks 6.3 Sedimentary Rocks 6.4 Metamorphic Rocks CHAPTER OUTLINE EXIT CHAPTER CHAPTER CHAPTER HOME Rocks VOCABULARY rock igneous magma sedimentary sediment 6.1 How Rocks Form In general, a rock is a group of minerals bound together Igneous, sedimentary, and metamorphic rocks are formed, broken down, and reformed in a recurring process called the rock cycle metamorphic rock cycle SECTION OUTLINE click image to enlarge CHAPTER CHAPTER HOME Rocks VOCABULARY felsic mafic pluton batholith SECTION OUTLINE 6.2 Igneous Rock Igneous rocks form as molten rock solidifies, as magma deep in the crust or lava at Earth’s surface cool Felsic magmas form light-colored, silica-rich rocks Mafic magmas form dark-colored rocks rich in iron and magnesiums Igneous rock texture depends mainly on the rate at which magma or lava cools Granite is igneous rock formed from felsic magma Basalt is igneous rock formed from mafic magma CHAPTER CHAPTER HOME Rocks VOCABULARY felsic mafic pluton batholith 6.2 Igneous Rock Igneous rocks are grouped into families by mineral composition and texture Chemical Composition Texture coarsegrained SECTION OUTLINE felsic granite felsicintermediate granodiorite intermediate diorite mafic gabbro ultramafic peridotite, dunite, pyroxenite finegrained glassy porous rhyolite obsidian most pumice andesite diabase basalt basalt glass scoria CHAPTER CHAPTER HOME Rocks VOCABULARY felsic mafic 6.2 Igneous Rock Magma that solidifies underground forms various types of igneous intrusions pluton batholith Volcanic neck Laccolith Volcano Stock Dike SECTION OUTLINE Sill Batholith CHAPTER CHAPTER HOME Rocks VOCABULARY cementation stratification fossil SECTION OUTLINE 6.3 Sedimentary Rock Sedimentary rocks form from sediments that result from weathering and erosion of rock at Earth’s surface They often occur in layers, formed over time as different sediments are deposited on top of each other CHAPTER CHAPTER HOME Rocks VOCABULARY cementation stratification fossil 6.3 Sedimentary Rock Sedimentary rocks are grouped by the type of sediment from which they form: clastic, chemical, or organic Clastic: Sandstone SECTION OUTLINE Chemical: Rock Salt Flat Organic: Limestone Cliffs CHAPTER CHAPTER HOME Rocks VOCABULARY cementation stratification fossil 6.3 Sedimentary Rock Clastic sediments are often sorted by water action before pressure and mineral cements turn them into rock A river moves sediment into a lake Sands and Gravels Conglomerate SECTION OUTLINE Particles are sorted by size The largest gravels are the first to be deposited, followed by sands, and then silt and clay Sands Sandstone Silt and Clay Shale Over time, the sediments are buried, compacted, and may be cemented CHAPTER CHAPTER HOME Rocks VOCABULARY cementation stratification fossil 6.3 Sedimentary Rock Clastic sediments are often sorted by water action before pressure and mineral cements turn them into rock Fossils, ripple marks, mud cracks, nodules, concretions, and geodes features associated with sedimentary rocks SECTION OUTLINE CHAPTER CHAPTER HOME Rocks VOCABULARY parent rock metamorphism 6.4 Metamorphic Rock Metamorphic rocks form when heat or pressure or both alter parent, or preexisting, rocks deform becomes Shale becomes Slate becomes SECTION OUTLINE Phyllite Schist CHAPTER CHAPTER HOME Rocks VOCABULARY parent rock metamorphism deform 6.4 Metamorphic Rock Metamorphic rocks form when heat or pressure or both alter parent, or preexisting, rocks Metamorphism can occur across a region, as in mountain building events, or it can occur in smaller local areas A metamorphic rock may be described and identified according to its parent rock, mineral composition, and texture SECTION OUTLINE CHAPTER Rocks CHAPTER HOME This is the end of the chapter presentation of lecture notes Click the CHAPTER HOME button or exit the presentation [...]...CHAPTER 6 CHAPTER HOME Rocks VOCABULARY parent rock metamorphism deform 6.4 Metamorphic Rock Metamorphic rocks form when heat or pressure or both alter parent, or preexisting, rocks Metamorphism can occur across a region, as in mountain building events, or it can occur in smaller local areas A metamorphic rock may be described and identified according to its parent rock, mineral composition, and... areas A metamorphic rock may be described and identified according to its parent rock, mineral composition, and texture SECTION OUTLINE CHAPTER 6 Rocks CHAPTER HOME This is the end of the chapter presentation of lecture notes Click the CHAPTER HOME button or exit the presentation