Planet Earth Test 1 Review .pdf

Class 3 -Earth’s interior layers: Chemical composition (Crust (Si+O)), (Mantle (Si, O, Mg, Fe)), (Core (Fe, Ni)) Iron(35%) Oxygen(30%) Silicon (15%) Magnesium(13%) Nickel (2.4%) Sulfur (1.9%) Calcium (1.1%) Aluminum (1.1%) Physical properties: Lithosphere (10-200km), Asthenosphere, mesosphere, outer...

Class 3 -Earth’s interior layers: Chemical composition (Crust (Si+O)), (Mantle (Si, O, Mg, Fe)), (Core (Fe, Ni)) Iron(35%) Oxygen(30%) Silicon (15%) Magnesium(13%) Nickel (2.4%) Sulfur (1.9%) Calcium (1.1%) Aluminum (1.1%) Physical properties: Lithosphere (10-200km), Asthenosphere, mesosphere, outer core, inner core -Earth’s Crust composition: O (46.3%) Si(28%) Al(8.1%) Middle Earth (mantle): (Fe+Si+O+Mg) Thickness~2,900 km, rock: peridotite -Continental crust: Composition (Si + O + Al), Granitic rocks, Thickness 40-70 km (oldest rocks on earth ~4.4 billion years), Thick/low density -Oceanic crust: Composition (Si + O +Fe + Mg), thickness (5-8 km), basaltic rocks, Thin/high density -The Moho: the boundary between the crust and mantle (mostly chemical) -The Guttenberg discontinuity: Boundary between mantle and core is sharp. Change in density across the core-mantle boundary is greater than at the earth’s surface -Lithosphere (10-200km): outermost layer rigid, solid, strong, and low temperature -Asthenosphere: Molten rocks, high temperature, weak, plastic, viscous, able to flow -Outer core: alloy of Fe+Ni, liquid, generates magnetic field -Inner core: alloy of Fe+Ni, solid Solar wind/flared of charger ions can damage satellites and other electric devices, earth’s magnetic field protects it from ions and solar radiation (mars and Venus have no magnetic field) Class 4/5 -Continental Drift Hypothesis (1960s-1990s): Alred Wegener (German meteorologist) all continents used to fit together, supercontinent Pangaea -Evidence for Continental Drift Hypothesis: 1. The fit of continents The shapes of N America, S America, Africa, and Europe. 2. The distribution of ancient climatic belts(past glacial deposits), 3. Fossil distribution: Fossils of land-dwelling organisms discovered in multiple continents, 4. Matching geologic units Rock units in Africa and S America match up, and Paleozoic mountain belts on either side of the Atlantic Ocean match up too (Failed to explain how his theory was rejected) -Pangea -Mantle convection: Arthur Holmes: Convection cells in the mantle as a mechanism for moving continents (occurs when a heated fluid expands and rises due to density differences), warned his ideas were purely speculative and had no scientific value until they acquire support from independent evidence -Mid-ocean ridge: Marie Tharp/Bruce Heezen -Bathymetry (depth of the ocean floor): first half-century scientists had no idea what the ocean bathymetry looked like, using echo sound a group of scientists in Columbia University began to map the ocean floor in the early 1950s -Echo sound: The travel time of the sound pulses indicates the seafloor's depth. -Mid-Atlantic ridge -Global heat flux -Seafloor spreading -Earth’s magnetic field -Liquid outer core -Magnetic polar wander -Magnetic reversals -Marine magnetic anomalies -Creation of new seafloor -Rifting – New Jersey/East African Rift - Age of Ocean Floor -Divergent Boundaries Class 6 -Convergent Boundaries -Transform/Strike-Slip -Active Margins -Passive Margins -Rate of Plate Movement -Subduction -Benioff Zone -Ocean-Ocean collision -Ocean-Continent Collision -Continent-Continent Collision -Continental Arc -Island Arc -Convection -Slab Pull -Ridge Push