Exam2_sample_fall2023

EAS 2600 Review Questions Learning Objectives (LO) : 6.1 Describe the major processes that form sedimentary rocks. 6.2 Compare the various types of sedimentary basins. 6.3 Define the different types of sedimentary environments and the two main types of sediments and sedimentary rocks. 6.4 Summarize the types of sedimentary structures. 6.5 Discuss the process of burial and diagenesis of sediments. 6.6 Describe how the major kinds of siliciclastic, chemical, and biological sediments are classified. 6.7 Discuss how carbonate and evaporite rocks are formed. 7.1 Explain the causes of metamorphism. 7.2 Describe the various types of metamorphism. 7.3 Summarize the various types of textural features displayed in metamorphic rocks. 7.4 Discuss the ways metamorphic rocks reveal the conditions under which they were formed. 7.5 Illustrate how metamorphic rocks are related to plate tectonic processes. 8.1 Compare the different types of tectonic forces at plate boundaries that deform rocks. 8.2 Describe how maps and diagrams are used to represent geologic structures. 8.3 Explain how laboratory experiments can help us understand the way rocks deform. 8.4 Summarize the basic deformation structures observed in the field and the types of forces that produce these deformation structures. 8.5 Define the main styles of continental deformation. 8.6 Describe how we reconstruct the geologic history of a region. 10.1 Explain how stress builds up on faults and is released in earthquakes through the process of elastic rebound. 10.2 Identify the three main types of seismic waves and describe the ground motions they produce. 10.3 Distinguish shaking intensity from earthquake magnitude and understand how they are related. 10.4 Classify earthquakes according to their plate-tectonic setting and patterns of faulting. 10.5 Characterize seismic hazards and the risks they pose to society and its built environment. 10.6 Defend the statement that “earthquakes can be forecast in the long term but not predicted in the short term.” 11.1 Trace the paths of the major seismic waves through Earth’s interior and know what they reveal about the layering of Earth’s crust, mantle, and core. 11.2 Apply the principle of isostasy to explain why continents ride higher than oceans and why the oceans deepen as the geologic age of the seafloor increases. 11.3 Recognize where heat in Earth’s interior is transported upward primarily by conduction and where primarily by convection. 11.4 Describe how temperature increases from Earth’s surface to its center, and identify the depths where the geotherm crosses the melting curve. 11.5 Visualize Earth’s three -dimensional structure from the images provided by seismic tomography. 11.6 Summarize what Earth’s magnetic field tells us about the liquid outer core. 11.7 Explain how magnetic field reversals are used to date rock sequences.

Sample Questions 1. A sample of marble has deformed brittlely during a laboratory experiment. If we wish our next sample of marble to deform plastically rather than brittlely, we should conduct the next experiment at . A) higher temperature and higher confining pressure B) lower temperature and lower confining pressure C) higher temperature and lower confining pressure D) lower temperature and higher confining pressure 2. A sediment initially composed of roughly equal amounts of quartz and feldspar grains is transported over a long distance. What will the sediment end up looking like? A) poorly-sorted, rounded grains consisting of mostly of feldspar B) well-sorted, angular grains consisting mostly of quartz C) well-sorted, rounded grains consisting mostly of quartz D) well-sorted, rounded grains consisting mostly of feldspar E) poorly-sorted, rounded grains consisting mostly of quartz 3. Which of the following is NOT a sedimentary structure? A) graded bedding B) ripples C) vesicles D) bedding E) cross-bedding 4. A geologist comes across a cross-bedded sandstone and notices all the grains are rounded and the same size. They have likely found a(n) A) ancient chemical sediment B) ophiolite suite C) ancient sand dune D) soil developed on basalt bedrock 5. Typically, as transport distance increases for sediment . A) sorting and rounding of particles decreases B) particle sorting decreases and particle rounding increases C) sorting and rounding of particles remains the same D) particle sorting increases and particle rounding decreases E) sorting and rounding of particles increases

6. A geologist finds a layer of halite (salt) and gypsum in a drill core taken in the sediments at the bottom of the Mediterranean Sea. The best interpretation of these layers is . A) at some point in the past the Mediterranean Sea must have dried up B) halite and gypsum layers were emplaced as sills in layers of other sediments C) at some point in the past the Mediterranean Sea had significant input of detrital halite and gypsum from rivers D) halite and gypsum layers formed from metamorphism of sedimentary muds E) halite and gypsum formed as dikes in layers of other sediments 7. The tendency for variations in current velocity to segregate sediments on the basis of particle size is called . A) metamorphism B) compaction C) lithification D) sorting E) diagenesis 8. Graded beds typically form . A) when crystals settle by density to the bottom of a magma chamber B) during the first stages of metamorphism C) during meteorite impacts D) when sands are carried by wind to form sand dunes E) when sediments deposit from a progressively weakening river current 9. What is the term for the process by which organisms burrow through muds and disrupt the sedimentary bedding? A) cementation B) cross-bedding C) chemical precipitation D) lithification E) bioturbation 10. A shale and a basalt are subjected to identical high pressure and temperature metamorphic conditions (Granulite). A geologist would expect A) minerals identical to those in each parent rock but recrystallized larger sizes B) minerals found in the two metamorphic rocks to be different C) minerals identical to those in each parent rock but recrystallized to polymorphs D) minerals found in the two metamorphic rocks to be approximately identical E) none of the above

11. If one dug a deep hole almost anywhere on the Georgia Tech campus, the rock that would most likely find would be? A) Gneiss B) Granite C) Limestone D) Shale E) Gabbro 12. What type of metamorphism is caused by high temperature and high pressure imposed over a large volume of crust? A) regional B) contact C) shock D) burial 13. The vast majority of the carbonate sediments of the ocean are derived from . A) fish and other vertebrates B) coral reefs C) direct inorganic precipitation of calcite from seawater D) calcite secreted by shelled organisms E) volcanic eruptions along mid-ocean ridges 14. Detrital sedimentary rocks are classified (named) primarily on the basis of . A) type of bedding B) particle size C) color D) composition E) none of the above 15. Which of the following metamorphic rocks is incorrectly paired with its parent rock? A) schist – slate B) marble – limestone C) schist – shale D) quartzite – shale E) none of the above 16. Cross-beds are a structure most commonly seen in A) chemical sediments B) shales C) lithified sand dune and river channel sediments D) bituminous coal horizons E) metamorphic rocks

17. Which of the following is an example of a clastic sedimentary rock? A) evaporite B) sandstone C) dolostone D) limestone E) chert 18. What kind of metamorphism would you expect to see in the rocks at a meteor impact site? A) contact B) burial C) hydrothermal D) shock E) regional 19. Which of the following lists the rocks in the order of increasing grain size and increasing grade of metamorphism? A) slate, phyllite, schist, gneiss B) gneiss, phyllite, slate, schist C) slate, schist, phyllite, gneiss D) phyllite, schist, gneiss, slate E) schist, slate, phyllite, gneiss 20. Metamorphism happens when rocks are subjected to A) changing temperatures B) changing pressures C) fluids inside the earth D) all of the above 21. In which of the following sedimentary rocks would it be easiest to determine the type of rocks from which the sediment was derived by eye (no magnification) A) limestones B) sandstones C) shales D) conglomerates E) siltstones 22. Metamorphic rocks CANNOT originate from . A) chemical sedimentary rocks B) igneous rocks C) siliclastic sedimentary rocks D) other metamorphic rocks E) none of the above