Geology Final Exam Students taking the final exam will be given 4 questions randomly selected from the list of 189 questions below. Each student will have their own set of 3-questions. There will be no repeat questions. To receive full credit (45-points), you must answer the question completely using proper geologic vocabulary to illustrate your answer. Additionally, students will provide at least 2-hand drawn diagrams for 2 of the 3 questions that enhance the completed question. It is extremely advisable that you learn and fully understand each answer to each question. Below is an example of a superior answer and poorly written answer to the same question. Students will be responsible for understanding the meaning of geologic vocabulary terms used throughout the semester. Students will be asked to define 5 vocabulary words randomly taken from the vocabulary list below. Final exam questions will be provided prior to each major exam and stored on the instructor’s website throughout the entire semester. Sample Question: Why do most major mountain chains contain metamorphic rocks in their cores? Superior Answer: All the mountain chains have formed at convergent plate boundaries that are characterized by increased pressure (confining and differential stress) and temperatures (geothermal and magmatism). Therefore, it is not surprising that such areas contain significant amounts of metamorphic rocks. Poorly written answer: Mountains are large hills that formed. Metamorphism takes place when rocks change. Chapter-1 Introduction to Physical Geology Vocabulary Terms asthenosphere catastrophism core hypothesis igneous rock sedimentary rock metamorphic rock mantle lithosphere relative dating absolute dating uniformitarianism superposition plate tectonics outer core Final Exam Questions 1. Geology is traditionally divided into two broad areas. Name and describe these two subdivisions. 2. Why was acceptance of the principle of uniformitarianism an important turning point in the history of geology? 3. How did proponents of the doctrine of catastrophism view the age of the earth? 4. What are the two sources of energy for the Earth System? 5. Identify and draw a diagram illustrating the two layers from the upper portion of the Earth’s interior. 6. Draw a cross-sectional view of the entire Earth and label the layers of the Earth’s interior. 7. Illustrate with a diagram the dominant motion of a transform boundary. 8. What principles were used to develop the geologic time scale? Describe each principle. 9. According to the rock cycle, can any rock be changed into another rock? 10. How does a scientific hypothesis differ from a scientific theory? Give an example of each. Chapter-2- Plate Tectonics Vocabulary Terms Asthenosphere Continental drift Oceanic ridge Plate tectonics Slab-pull Volcanic arc system Divergent plate boundary Convergent plate boundary paleomagnetism rift valley subduction zone transform fault boundary lithosphere hot spot Pangaea seafloor spreading trench Final Exam Questions 11. Draw a diagram illustrating the divergent plate boundary. Identify the mid-ocean ridge, rift zone, oceanic and continental crust, and arrows depicting plate motion. Identify a geographical location where this type of boundary occurs. 12. Draw a diagram showing the 3-types of convergent boundaries. Identify the subduction zones, ascending magma, island and or volcanic mountain chain, oceanic and continental crust, and asthenosphere. Identify a geographical location where this type of boundary occurs. 13. Draw a diagram illustrating the transform fault boundary. Include in your diagram plate motion arrows, an off-set erosional feature, and continental crust. Identify a geographical location where this type of boundary occurs. 14. What evidence did Alfred Wegener use to support the continental drift hypothesis? 15. Where is lithosphere being formed? Consumed? Why must the production and destruction of the lithosphere occur at the same rate? 16. Why is oceanic lithosphere subducted while continental lithosphere is not? 17. What is the primary difference between transform faults and the two other types of plate boundaries? 18. Specifically, what type of plate boundary is associated with the following: Himalayas, Aleutian Islands, Red Sea, the Andes, San Andreas Fault, Iceland, and Japan? 19. How do hot spots and the plate tectonics theory account for the fact that the Hawaiian Islands vary in age? 20. What was the defining evidence that separates the Continental drift theory from the Plate Tectonic theory, and how this evidence is used to explain that continents are in fact moving? 21. Briefly describe the view held by most geologists regarding the ocean basins and continents prior to the 1960’s 22. What was the first line of evidence that led early investigators to suspect the continents were once connected? 23. Explain why the discovery of the fossil remains of Mesosaurus in both South America and Africa, but nowhere else, supports the continental drift hypothesis. 24. What two aspects of Wegener’s continental drift hypotheses were objectionable to most Earth scientists? 25. What major ocean floor feature was discovered by oceanographers following World War II? 26. Compare and contrast the lithosphere and the asthenosphere. 27. List the seven largest lithospheric plates. 28. List the three types of plate boundaries and describe the relative motion at each of them 29. Draw distinct diagrams that represent the divergent, convergent, and transform tectonic boundaries. 30. What is the average rate of seafloor spreading in modern oceans? 31. Briefly describe the process of continental rifting. Where is it occurring today? 32. Explain why the rate of lithosphere production roughly balances the rate at which it is destroyed? 33. Compare a continental volcanic arc and a volcanic arc island are. 34. Why does oceanic lithosphere subduct while continental lithosphere does not? 35. Differentiate between transform faults and the two other types of plate boundaries. 36. Describe how Fred Vine and D.H. Matthews related the seafloor-spreading hypothesis to magnetic reversals. 37. Briefly explain the process of convection. Draw a diagram showing convection. 38. Describe slab pull and ridge push. Which of these forces contributes more to plate motion? 39. What role are mantle plumes thought to play in the convective flow of the mantle? 40. Briefly describe the two models proposed for mantle-plate convection. What is lacking in each of these models? Chapter-3 Matter and Minerals Vocabulary Terms Atom atomic number Covalent bond ionic bond Mineral physical properties Isotope silicate mineral chemical compound element mineral proton electron crystal form neutron ore Final Exam Questions 41. Describe the bonding characteristics of both the covalent and ionic bonds. 42. What is the difference between a mineral and a rock? 43. Although minerals possess an orderly internal arrangement of atoms, most mineral samples do not exhibit their crystal form. Why? 44. Why are silicates the most important group of minerals? 45. What is the purpose of the valance electron shell? 46. Draw a diagram showing the typical atom model and identify the protons, electrons, and neutrons. 47. Define an ion and the differences between a cation and anion. Give two examples of cations and two examples of anions. 48. Draw a diagram of a silicate-tetrahedron. Define at least 3-important characteristics that make this particular compound important to minerals and rocks. 49. Why is color generally the most unreliable physical property to use when identifying a mineral? 50. Define the differences between the physical properties cleavage and fracture. 51. Describe the bonding characteristics of both the covalent and ionic bonds. 52. What is the difference between a mineral and a rock? 53. Although minerals possess an orderly internal arrangement of atoms, most mineral samples do not exhibit their crystal form. Why? 54. Why are silicates the most important group of minerals? 55. What is the purpose of the valance electron shell? 56. Draw a diagram showing the typical atom model and identify the protons, electrons, and neutrons. 57. Define an ion and the differences between a cation and anion. Give two examples of cations and two examples of anions. 58. Draw a diagram of a silicate-tetrahedron. Define at least 3-important characteristics that make this particular compound important to minerals and rocks. 59. Why is color generally the most unreliable physical property to use when identifying a mineral? 60. Define the differences between the physical properties cleavage and fracture. 61. Choose two minerals that you know and indicate their chemical make-up and their uses. 62. What is the definition of a mineral and list three examples of material that does not qualify as a mineral? 63. What mineral is the hardest known substance in nature and what properties make this particular mineral the hardest natural substance known to man? 64. If you found a glassy-appearing mineral while rock and mineral hunting, and had hopes that it was a diamond, what simple test might help you make a determination? Explain you’re rational. 65. Explain why it might be difficult to identify a mineral by its color. 66. List the three main particles of an atom and explain how they differ from one another. 67. If the number of electrons in a neutrally charged atom is 35 and the atomic mass is 80, calculate the following: a. The number of protons b. The atomic number c. The number of neutrons 68. What is Mohs scale of hardness? List Mohs the minerals that make up Mohs scale of hardness form softest to hardest. Identify various “tools” that one can use in the field to measure the hardness of minerals. 69. Choose 3 mineral physical properties and describe how the method used to determine each property. 70. What is your favorite mineral and what physical property tests would describe your mineral. Chapter-4 – Magma, Igneous Rocks, and Intrusive Activity Vocabulary Terms Bowen’s reaction series andesitic composition granitic composition phaneritic texture pegmatitic texture batholith pahoehoe flow pluton crystallization basaltic composition mafic porphyritic texture ultramafic dike volatiles intrusive extrusive felsic groundmass aphanitic texture phenocryst pyroclastic texture magmatic differentiation laccolith aa flow sill xenoliths Final Exam Questions 71. In general, what happens in terms of composition as crystallization proceeds down the Bowen’s reaction series? 72. What is the role of water and other volatiles that are driven from the descending plate in the diagram below? 73. What is the difference between magma and lava? 74. What are the two criteria used to classify igneous rocks? 75. What are two conditions or situations that are thought to promote the melting of rocks? 76. What does a porphyritic texture indicate about the cooling history of an igneous rock? 77. Describe the difference between a phaneritic and aphanitic textures and what geological environment allows theses textures to form. 78. Why are the crystals of pegmatites so large? 79. How are granite and rhyolite different? In what way are they similar? 80.Given the igneous rocks basalt, rhyolite, and andesite, arrange these rocks in order of increasing silica. Chapter-5- Volcanoes and Volcanic hazards Vocabulary Terms Fissure eruption Lahar Scoria Pillow lava Pyroclastic material flood basalt Nuee ardent lava tube pumice composite cone hot spot shield volcano cinder cone volcano intraplate volcanism stratovolcano viscosity volatiles Final Exam Questions 81. Draw a simple diagram of a volcano and label the flanks, conduit, caldera, and magma chamber 82. Define the three factors that control the viscosity of a magma. 83. Why are magmas with higher viscosity more likely to produce explosive eruptions? 84. Which type of volcano is the largest? Which type is most explosive? Why? 85. What is the Ring of Fire and how is it related to plate tectonics? 86. How does the concentration of SiO2 influence magma viscosity? 87. How does the concentration of volatiles determine an eruptive style for both shield and composite volcanoes? 88. Why are voluminous pyroclastic flow deposits primarily associated with composite type volcanoes? 89. Define a lahar and why are lahar’s consider a major volcanic hazards 90. What type of volcano possesses the biggest threat to loss of life and wide damage? Why? 91. List three factors that determine the nature of a volcanic eruption. What role does each play? 92. What is viscosity? How does the chemistry (concentration of SiO2) influence magma’s viscosity? How does temperature influence magma’s viscosity? 93. Why is a volcano fed by highly viscous magma likely to be greater threat to life and property than a volcano supplied with very fluid magma? 94. Describe the characteristics of pahoehoe and aa lava flows. What main factor distinguishes the difference in flow rates between each type of basaltic lava flow? 95. List the main gasses released during a volcanic eruption. 96. How do volcanic bombs differ from blocks of pyroclastic debris? 97. What is scoria? How is scoria different from pumice? 98. Compare a volcanic crater to a caldera. 99. Compare and contrast the three main types of volcanoes (consider size, composition, shape and eruptive style). 100. Name a prominent volcano for each of the three main types. 101. Sketch a volcano and identify its morphologic parts: crater, volcanic conduit, flanks, magma chamber, and caldera (assuming the volcano is dormant) 102. Extensive pyroclastic flow deposits are associated with which volcanic structure? 103. How to the eruptions that created the Columbia Plateau differ from eruptions that create large composite cones? 104. What is Shiprock, New Mexico, and how did it form? 105. Draw a diagram of various intrusive bodies and label the following: dike, sill, batholith, and laccolith structures 106. What is the largest of all intrusive igneous bodies? Is it tabular or massive? Concordant of discordant? 107. Define geothermal gradient. 108. Describe the three ways that solid rocks in the upper mantle and crust may melt to become magma. 109. What is decompression melting and how does it occur. What is partial melting? 110. How is magma generated along convergent plate boundaries? 111. Volcanism at divergent plate boundaries is associated with which rock type? 112. Volcanism at ocean to continent plate boundary is associated with what type of igneous rocks? 113. Describe four natural hazards associated with volcanoes. 114. What are the four changes in a volcanic area that are monitored in order to detect the migration of magma? Chapter-6 Weathering Vocabulary Terms Chemical weathering External processes Internal processes Parent material Soil profile erosion frost wedging mass wasting regolith soil taxonomy exfoliation dome horizon mechanical weathering soil weathering 115. Describe the role external processes in the rock cycle. 116. If two identical rocks were weathered, one mechanically and the other chemically, how would the products of weathering for the two rocks differ? 117. Describe the formation of an exfoliation dome. Give an example of such a feature. 118. How does mechanical weathering add to the effectiveness of chemical weathering? 119. Heat speeds up a chemical reaction. Why than does chemical weathering proceed slowly in a hot desert? 120. How is carbonic acid formed in nature? What results when this acid reacts with potassium feldspar? 121. List some possible environmental effects of acid precipitation. 122. What is the difference between soil and regolith? 123. What factors might cause different sills to develop from the same parent material? 124. Which of the controls of soil formation is most important? Chapter-7 Sedimentary Rocks Vocabulary Terms Bedding plane Cementation Compaction Lithification beds chemical rock crystalline texture sedimentary environment biochemical clastic texture evaporate deposit 125. How does the volume of sedimentary rocks in Earth’s crust compare with the volume of igneous rocks in the crust? 126. List and briefly distinguish among the three basic sedimentary rock categories. 127. What minerals are most common in detrital sedimentary rocks? Why are these minerals so abundant? 128. What is the primary basis for distinguishing among various detrital sedimentary rocks? 129. Distinguish between conglomerate and breccias 130. What are evaporate deposits? Name a rock that is an evaporate. 131. When a body of seawater evaporates, minerals precipitate in a certain order. What determines this order? 132. What is the primary basis for distinguishing among different chemical sedimentary rocks? 133. What is diagenesis? Give one example. 134. List the three common cements for sedimentary rocks and explain how these cements lithify various types of sediments. 135. Distinguish between clastic and non-clastic textures. Chapter-8 Metamorphic Rocks Vocabulary Terms Confining pressure Gneissic texture Metasomatism Parent rock Schistosity differential stress metamorphic facie migmatite protolith texture foliation metamorphism non-foliated texture regional metamorphism Review the following questions on page 252 Questions 1,3,4,6,7,9,10,11,12,14,16,17,18,19 Chapter-9 Geologic Time Vocabulary Terms Angular unconformity Cross-cutting relations Epoch Geologic time scale Nonconformity Paleozoic era Precambrian Superposition Archean eon disconformity fossil half-life original horizontality period radiometric dating unconformity Cenozoic era eon fossil succession Mesozoic era paleontology Phanerozoic eon relative dating Review the following questions on page 276 Questions 1,2,4,5,6,7,8,10,11,12 Chapter-11 Earthquakes Vocabulary Terms Aftershock Elastic rebound Hypocenter Moment magnitude Secondary waves Seismogram body wave epicenter magnitude primary wave seismic gaps seismograph earthquake focus Mercalli Intensity Scale Richter Scale seismic waves surface wave Review the following questions on page 331 1, 2, 4, 5, 7, 8, 13, 14, 15, 21, 25 Chapter-10 Crustal deformation Vocabulary Terms Anticline Differential stress Fold Hanging wall block Reverse fault Strike Tensional stress compressional stress dip footwall block joint strain strike-slip fault thrust fault deformation fault fault scarp normal fault stress syncline transform fault Review the following questions on page 300 3, 4, 8, 11, 12, 14, 17,18 Chapter-19- Deserts Vocabulary Terms Abrasion Alluvial fan Bajada Transverse dune Dune slip face deflation desert desert pavement barchan dune loess longitudinal dune parabolic dune playa rain shadow desert Review the following questions on page 538 Questions 1, 3, 5, 8, 11, 12, 15-18 Chapter-19- Mass Wasting Vocabulary Terms Angle of repose Creep Debris flow Slide Debris slide debris slide mass wasting fall permafrost lahar earthflow rockslide mudflow slump rock avalanche Review the following questions on page 426 Questions 1-6, 8-16