Lecture 3: The Rock Cycle - Formation & Classification of Rocks, Slides of Geology

Download Lecture 3: The Rock Cycle - Formation & Classification of Rocks and more Slides Geology in PDF only on Docsity! GY 111: Physical Geology Lecture 3: The Rock Cycle Last Time 1. Alfred Wegener and “Drifting Continents” 2. The Plate Tectonic Revolution 3. Plate Tectonics Mechanisms Alfred Wegener Matching rock types and fossils* * types and ages Radar, sonar, and depth sounding revealed that the ocean bottoms were not flat planes The Plate Tectonics Revolution Earth has a magnetic field (and it isn’t constant) The Plate Tectonics Revolution Paleomagnetism shows that the ocean floor youngest near the ridges and oldest near the continents The Plate Tectonics Revolution Docsity.com Internal “guts” of the Earth Four Major “Geophysical” Layers 1) The Crust 2) The Mantle 3) The Outer Core 4) The Inner Core (1270 km; solid metal) Cooler Hotter The Plate Tectonics Mechanism Collectively, the rigid outer most part of the Earth (about 100 km thick) is called the Lithosphere Crust Mantle Geophysical layers Lithosphere: Athenosphere: Tectonic layers The Plate Tectonics Mechanism Tectonic plates can interact in one of 3 ways 1) Move away from one another: Divergent Plate Boundary 2) Move towards one another: Convergent Plate Boundary 3) Slide past one another: Transform Fault Plate Boundary Today’s Agenda 1. More on Alfred Wegener 2. Introduction to rocks 3. The Rock Cycle Web notes 3: Alfred Wegener Docsity.com Igneous Rocks Can be either extrusive (volcanic) or intrusive (plutonic): Extrusive (volcanic) rocks can be erupted as lava… Igneous Rocks Can be either extrusive (volcanic) or intrusive (plutonic): Extrusive (volcanic) rocks can be erupted as lava, or as pyroclastic material (e.g., ash) Sedimentary Rocks Sedimentary Rocks We recognize 4 major classes of sedimentary rocks: Sedimentary Rocks We recognize 4 major classes of sedimentary rocks: 1) Siliciclastic: composed of broken bits of silicate minerals; Alluvial fan Sedimentary Rocks We recognize 4 major classes of sedimentary rocks: 1) Siliciclastic: composed of broken bits of silicate minerals 2) Biochemical: mostly composed of the remains of calcium carbonate-secreting beasties reef Docsity.com Sedimentary Rocks We recognize 4 major classes of sedimentary rocks: 1) Siliciclastic: composed of broken bits of silicate minerals 2) Biochemical: mostly composed of the remains of calcium carbonate-secreting beasties 3) Chemical; formed through chemical precipitation alteration Salt flat Sedimentary Rocks We recognize 4 major classes of sedimentary rocks: 1) Siliciclastic: composed of broken bits of silicate minerals 2) Biochemical: mostly composed of the remains of calcium carbonate-secreting beasties 3) Chemical; formed through chemical precipitation alteration 4) Organic; formed from plant material Peat bog Metamorphic Rocks Metamorphic Rocks We recognize 3 divisions of metamorphic rocks: Metamorphic Rocks We recognize 3 divisions of metamorphic rocks: 1) Foliated; display a prominent layering schist Metamorphic Rocks We recognize 3 divisions of metamorphic rocks: 1) Foliated; display a prominent layering 2) Non-foliated; do not display layering marble Docsity.com Metamorphic Rocks We recognize 3 divisions of metamorphic rocks: 1) Foliated; display a prominent layering 2) Non-foliated; do not display layering 3) Cataclastic; composed of broken up bits of rock mylonite The Rock Cycle The Rock Cycle The Rock Cycle The Rock Cycle Metamorphic Loop Sedimentary Loop Igneous Loop Today’s Homework 1. Download and read web notes 3 2. Organize your notes Next Time 1. Quiz 2 2. Basic Chemistry Docsity.com