EOSC 110 Midterm One Exam Questions And Answers Verified 100% Correct

EOSC 110 Midterm One Exam Questions And Answers Verified 100% Correct What is a diapir? - ANSWER -Rising bodies of magma What is a pluton? - ANSWER -Large igneous bodies that crystallize depth within the Earth's crust. What is batholith? - ANSWER -Large (100km2) igneous bodies formed by the coalescence of plutons. How are intrusive bodies exposed to surface? - ANSWER -Uplift and erosion What is a dyke? - ANSWER -Vertical and goes against grain of rock What is a sill? - ANSWER -Horizontal and goes against the grain of rock Why is weathering important? - ANSWER -Creates sedimentary rocks, economic commodities, creates landforms and landscape development. Mechanical weathering processes? - ANSWER -Frost wedging, root wedging, salt wedging, thermal heating and cooling, gravity, physical force. Chemical weathering processes? - ANSWER -Oxidation, solution/dissolution, hydration Features due to weathering? - ANSWER -Arches, grand canyon, erosion of rocks How do sedimentary rocks fit into the rock cycle? - ANSWER -They form from igneous and metamorphic rocks turning into sediment through weathering and erosion. The sediment then goes through lithification and turns into sedimentary rock. How are clastic sedimentary rocks formed? - ANSWER -1. Weathering (mechanical) produces fragments 2. Transportation through water and wind 3. Deposition (marine on land) 4.Compaction and cementation, reduce pore space, cement (quartz, calcile, hermatile), binds grains together (lithification) forms detrital rocks. How are chemical sedimentary rocks formed? - ANSWER -1. Weathering (chemical) ions in solution 2. Transportation through dissolved ions and ionic groups in water 3. Precipitation organic and inorganic form new sedimentary rocks Bedding - ANSWER -The arrangement of sedimentary rocks into layers allow for scientists to look at fossils and understand when things happened in relation to the rock. Cross Beds - ANSWER -Basically wind patterns in rock surface, can be used to tell what way the wind went , as well as intensity. Mud Cracks - ANSWER -Cracks in mud show that there is seasonal precipitation or that at one point much more water was present. Ripples Marks - ANSWER -Indicates currents/tides direction and intensity Fossils - ANSWER -Help explain how old rocks are as well as where they once were. How do metamorphic rocks fit into the rock cycle? - ANSWER -Almost any rock can be metamorphic, through different ways the metamorphic rocks are the central part of the rock cycle, and is the rock that melts to restart the process. What forces drive metamorphism? - ANSWER -1. Changes in Temperature 2. Changes in Pressure 3. Fluids What is the geothermal gradient? - ANSWER -The amount of increase in temperature with depth in Earth. What is the average geothermal gradient? - ANSWER -25C/KM depth What does lithostatic mean? - ANSWER -Increase in pressure equal in all directions Can compressive stress produce foliation? - ANSWER -Yes, but only with very platy minerals. What changes in rocks during metamorphism? - ANSWER -1. Recrystallization (coarsening) 2. Formation of new minerals 3. Foliation Contact metamorphism - ANSWER -Adjacent to intrusions in shallow crust, country rock heated by conduction and hydrothermal convection Regional metamorphism - ANSWER -Occurs over large areas of the crust due to increased P-T at depths 5KM What does contact metamorphism result in? - ANSWER -Recrystallization, new minerals, veins form What does regional metamorphism result in? - ANSWER -Recrystallization, new minerals form, metamorphism foliation develops Three stages of divergent boundary? - ANSWER -1. Rift valley 2. Continued rifting 3. Mature ocean basin What are the layers of Earth and what are they like? - ANSWER -1. Inner Core (solid