EARTH SCIENCE FINAL EXAM QUESTIONS AND ANSWERS

EARTH SCIENCE FINAL EXAM QUESTIONS AND ANSWERS List the 3 main layers of the earth from the center to the outside based on composition (what they are made out of). - Correct Answer ️️ -1). Core (Inner and outer)-solid inner liquide outer. Iron/nickel alloy. Extreme pressure 2).Mantle-82% of the earth's volume-Solid, rocky, shell 3). Crust (Oceanic-younger rocks and Continental-granite rocks) List the 5 mechanical layers of the earth (based on how they deform?) Whic layers is a liquid? - Correct Answer ️️ -1.The lithosphere is the outermost mechanical layer and is the most rigid layer of the Earth. The lithosphere consists of the crust, and some of the uppermost mantle. The lithosphere averages about 100 km thick. It is somewhat thicker beneath continents, and dramatically thinner under mid-ocean ridges. 2.The asthenosphere lies beneath the lithosphere. It is a part of the mantle, approximately 100 km thick, with very little strength. The asthenosphere flows relatively easily and accomodates the movement of the overlying lithosphere. The upper and lower boundaries of the asthenosphere are diffuse as they involve gradual changes in the rigidity of the mantle, not a change in composition. 3.The lower mantle or mesosphere consists of most of the mantle. This part of the mantle flows, but at much slower rates than the asthenosphere. 4.The outer core is liquid iron (with some nickel and other elements). This is the only internal layer of the Earth that is a true liquid. The core-mantle boundary is the one mechanical boundary that is also a compositional boundary. Movement of the electically conductive fluid in the outer core generates the Earth's magnetic field. 5.The inner core is solid. It has the same composition as the outer core, and is about half the diameter of the core. What were four pieces of evidence that Wegener used in 1912 to support his theory of continental drift? - Correct Answer ️️ -1). Jigsaw fit of continents 2). Fossil Coninuity 3).Ancient Glaciations Match 4).Mountain Ranges Match What did Wegener's Theory lack (what did he get wrong)? - Correct Answer ️️ -How the continents moved. Did not have a logical answer to this. He felt... What is seafloor Spreading and what is the evidence of this? - Correct Answer ️️ -New oceanic crust form at spreading center-Age of seafloor increases as you move away from the ridge. Evidence: 1).Paleomagnetism (magnetic pattern of seafloor)-Matching polarities on either side of ridge show that all oceanic crust formed at ridge 2). Magnetic Reversals&Age Bands: Seafloor spreading in past 180 my shown by symmetrical bands of relative rock age and magnetic polarity on either side of ridge. Describe the lithosphere in detail?What layers of the earth make it up? Is it solid or liquid? How does it deform (by flowing or by breaking)? - Correct Answer ️️ - Lithosphere (sphere of rock)=the plates=all of the crust and the upper most part of the mantle. Brittle solid-deforms by breaking. Moves around on the top of the astenosphere Describe the asthenosphere in details? In waht layer of the earth is it contained? Is it solid or liquid? - Correct Answer ️️ -Astehnsophere (weak sphere)-plastic solid- deforms by flowing. This is where warm material rises up and cooler material sinks- convection that drives the plates apart and together. Summarize the theory of plate tectonics. - Correct Answer ️️ -Plate Tectonics Theory- states that the lithosphere is divided into ~30 rigid plates that are slowly moving about the surface of the planet from forces within (asthenosphere) the Earth. The plates may move together, apart or slide past each other. Types of stress that causes deformation of rocks. - Correct Answer ️️ -Pushing together (compression); Pulling apart (Tensional); Shear (slide past each other. What is the divergent boundary: What features are formed there? Draw One. - Correct Answer ️️ -A boundary at which two plates move apart. 1) Divergent-Mid Ocean Ridge - Oceanic-Oceanic 2).Divergent-Continental Rift-continental/Continental What is transform Boundary? What features are formed there? Draw One. - Correct Answer ️️ -A boundary in which two plates slide past each other without creating or destroying the lithosphere. What is convergent boundary? Describe all 3 types) What can be formed at each one? Draw them. - Correct Answer ️️ -1). Convergent - Subduction oceanic - continental FORMED: ?? (trench) 2). Convergent - Subduction oceanic - oceanic Formed?? 3).Convergent - Collision continental - continental -Mountain Range-high Plateau. What are convection currents?What (layer) do they happen and why are they significant for plate tectonics? - Correct Answer ️️ -The motion of matter resulting from changes in temperature The convection flow of material in the mantle is due to Earth's unequal heating and causes the tectonic plates to move. (269) WHere dows the energy come from that drives plate movement? - Correct Answer ️️ - Heat from the core. What is a Mid Ocean Ridge - Correct Answer ️️ -A continuous elevated zone on the floor of all the major ocean basins. The rifts at the crests of ridges represent divergent plate boundaries. What is Paelomagnetism - Correct Answer ️️ -The study of changes in Earth's magnetic fields, as shown by patterns of magnetism in rocks that have formed over time.