Geology EXAM 2 Content

Quiz 9: Earthquakes

Q1) A P-wave, is a type of ______ wave which is ______ , meaning that particle motion is in the direction of wave propagation (wave travel). A: Answer 1 - body Answer 2 - compressional _____________________ Q2) Which of the following would be the MOST destructive earthquake: A: A shallow earthquake of moderate magnitude close to a city built on sediments. _____________________ Q3) Which of the following are true of surface waves? (select all that apply) A: only travel along Earth's surface slowest waves _____________________ Q4) Which seismic waves have the largest amplitude? A: Surface waves _____________________ Q5) Intraplate earthquakes are not well understood, but earthquakes along the New Madrid fault zone in Missouri are likely due to: A: activity along old faults related to the breakup of a supercontinent _____________________ Q6) Some areas along the San Andreas fault do not experience earthquakes. This is due to _______. A: fault creep _____________________ Q7) On the seismogram reading below ... A: A shows - P waves B shows - S waves C shows - Surface waves _____________________ Q8) In order to locate the epicenter of an earthquake, you need which of the following? (select all that apply) A: Time difference between the arrival of the P and S waves, At least 3 seismic recording stations _____________________ Q9) Earthquakes on Hawaii are caused by: A: magma movement _____________________ Q10) Liquefaction occurs when: A: ground shaking causes water-saturated sediments to loose contact with one another and flow like a fluid. _____________________ Q11) Seismic waves are produced during an earthquake and are recorded by geologists on ___________. A: seismographs _____________________ Q12) _______ precede an earthquake and ________ follow a major earthquake. A: foreshocks / aftershocks _____________________ Q13) Which of the following materials is most stable during ground shaking? A: bedrock _____________________ Q14) The entire west coast of the United States experiences earthquakes. In central and Southern California this is due to _______ , and in Northern California, Oregon, and Washington, this is due to ________ . Nevada, Utah, Idaho, Colorado, etc. experience earthquakes due to ________. A: Answer 1 - strike-slip faulting Answer 2 - megathrust faulting Answer 3 - normal faulting _____________________ Q15) The Richter magnitude scale assigns a number to an earthquake that represents the amount of energy released. Between a magnitude 7 and magnitude 8 earthquake, the magnitude 8 releases _______ times more energy. A: 32

Mod 9 Participation

Q1) Can humans cause earthquakes? A: Yes _____________________ Q2) Fill in the blanks to describe elastic rebound theory. The theory that potential energy is stored in a fault by ______ strain of rock, once the strength of the rock is exceeded, the fault will rupture and the two fault blocks will ______ , releasing the energy in the form of ______ . A: Answer 1 - elastic Answer 2 - return to their original shape Answer 3 - seismic _____________________ Q3) What is one of the differences between body waves and surface waves? A: Body waves are described as compressional or shear _____________________ Q4) To locate the epicenter of an earthquake, what information do you need? A: the difference in the arrival times of the P- and S-waves, as recorded at three different stations _____________________ Q5) How much more energy is released by a magnitude 7 earthquake than a magnitude 5 earthquake? A: 1024x _____________________ Q6) Earthquake magnitude refers to ______ , whereas earthquake intensity refers to ______ ? A: Answer 1 - energy release Answer 2 - degree of ground shaking _____________________ Q7) What type of fault is the most destructive? A: reverse/thrust _____________________ Q8) Earthquakes in the New Madrid seismic zone are examples of what type of earthquakes? A: intraplate earthquakes _____________________ Q9) Which of the following contributed least significantly to the devastation caused by the earthquake in Haiti? A: The large magnitude of the earthquake _____________________ Q10) If you build a house in an earthquake-prone area, which of the following would be the best choice for building materials? A: wood _____________________ Q11) What soil conditions lead to liquefaction? (select all that apply) A: ground shaking water saturated pore space loose sediment/soil _____________________ Q12) Why are fires a hazard associated with earthquakes? A: broken gas lines _____________________ Q13) Using this earthquake map for the United States, determine which area in the list below has the highest earthquake hazard. A: South Alaskan coast _____________________ Q14) Making better _________ is the best way to prevent earthquake damage. A: buildings _____________________ Q15) Where do you think is the best place to be during an earthquake? A: In an empty field

Mod 6 Participation

Q1) Frost wedging occurs because: A: Water occupies less volume than ice. ----------- Q2) Which of the following influences the rate of weathering of rocks? (check all that apply): A: The minerals that make up a rock, Presence of water, Presence of vegetation and types of plants in a region, Temperature and climate of the region. ----------- Q3) In terms of weathering rates, Shiprock, New Mexico, is most likely an example of: A: Differential rates of weathering �between weaker extrusive and �stronger intrusive igneous �rocks. ----------- Q4) Recall Earth's spheres (atmosphere, geosphere, hydrosphere, and biosphere), soil is considered an interface between spheres because: A: contains water, air, rock, and organic matter. ----------- Q5) Match the main control each of these might have on soil formation: a. Affects the chemical composition of the soil - bedrock composition b. Affects the thickness of the soils - bedrock composition c. Affects the moisture content of the soil - Topography d. Affects how much sunlight an area receives - Topography e. Provide organic material for soil formation - Local Ecosystem f. Burrowing animals help mix mineral and organic portions of the soil - Local Ecosystem g. Affects the thickness of the soils - Time ----------- Q6) The O and A horizons of the soil profile are important for what reason? A: They are a mixture of sediments and organic matter than make up nutrient-rich topsoil. ----------- Q7) Sedimentary Rocks are formed by: A: Deposition from a solution, The lithification of sediments ----------- Q8) Sedimentary rocks are particularly important to humans because: A: They contain resources such as water, oil and gas, uranium, and iron. ----------- Q9) The process of forming a clastic sedimentary rock is best described by which of the following? A: Weathering, transportation, deposition, lithification ----------- Q10) Which of the following sediments have been transported the furthest? A: fine grained, well rounded, well sorted ----------- Q11) Why is a swamp environment the best for accumulation of thick layers of organic material that eventually can become coal? A: Swamps are stagnant and the decomposition of organic material impedes the growth of bacteria. ----------- Q12) Which of the following processes forms biochemical sedimentary rocks? A: Cementing together of shell fragments ----------- Q13) Coal is a form of ____________. A: Organic sedimentary rock ----------- Q14) Which of the following contributes to the sequestration of carbon dioxide? (which is a fancy word for take out of the atmosphere and store -- the opposite of release) A: Photosynthesis, Burial of biomass (plants), Formation of limestone ----------- Q15) What is the single-most common characteristic feature of sedimentary rocks. A: Beds ----------- Q16) In the topmost cross bed, which direction was wind likely blowing when this layer formed? A: To the Left ----------- Q17) What rock would we expect to find at a coral reef? A: Limestone

Quiz 7: Metamorphism and Deformation

Q1) In the following figure, the block on the left is the _______ and block on the right is the _______ . This is an example of a _____ fault. A: Answer 1: hanging wall Answer 2: foot fall Answer 3: reverse --------------- Q2) Which of the following mountain building processes can have associated volcanoes? A: subduction, continental rifting --------------- Q3) The image shown below is an example of: A: confining pressure --------------- Q4) The following image shows a ______ fault. A: right lateral strike-slip --------------- Q5) Imagine a protolith composed of clay and quartz. This rock is later subjected to intense pressures and temperatures during a mountain building event. After this event, the rock no longer contains clay and quartz, but instead, garnet and mica, what metamorphic process took place? A: neocrystallization --------------- Q6) Which of the following is the most important agent of metamorphism? A: changes in temperature --------------- Q7) The Appalachian Mountains: A: formed from three major orogenies: The Taconic, The Acadian, and the Alleghenian orogenies. --------------- Q8) Which of the following is true of fractures, joints and faults? A: Faults and joints are types of fractures. The difference is faults show displacement and joints do not. --------------- Q9) In which of the following would you expect to see the MOST amount of change from the protolith to the metamorphic rock that forms during metamorphism. A: High grade metamorphism --------------- Q10) Match the BEST metamorphic environment to the correct location on the following figure: A: A - thermal metamorphism B - regional metamorphism C - subduction metamorphism D - hydrothermal metamorphism --------------- Q11) Which of the following is a foliated rock? (select all that apply) yes = foliated, no = not foliated A: eclogite - yes sandstone - no gneiss - yes quartzite - no --------------- Q12) Order the following from lowest temperature process (1) to highest temperature process (3). A: Metamorphic rock formation - 2 Igneous rock formation - 3 Sedimentary rock formation - 1

Quiz 8: Geologic Time

Q1) Petrified wood, ie. wood that has been mineralized by groundwater, is an example of: A: permineralization --------------- Q2) A sequence of folded rocks must be older than the event that deformed them. This is an example of the principle of: A: original horizontality --------------- Q3) What is uniformitarism? A: The present is the key to the past --------------- Q4) Minerals dated by radioactive isotopes in a sedimentary rock are usually: A: older than the sedimentary rock --------------- Q5) Why are zircons particularly good for dating old rocks?: A: They have high melting temperatures and last through partial melting events When they crystallize they only take up U in their crystal structure. --------------- Q6) The Cambrian explosion of life occurred: A: ~540 million years ago --------------- Q7) Which of the following are true about carbon dating? (select all that apply) A: It is useful only for relatively young events since it has a relatively short half life compared to geologic time Carbon-14 is formed in Earth's atmosphere by reaction with cosmic rays It is useful for only organic materials Carbon-14 is incorporated into plants through photosynthesis Carbon-14 is radioactive --------------- Q8) Gastroliths, coprolites, and burrows are all __________. A: trace fossils --------------- Q9) The Hadean eon: A: was a particularly hot time in Earth history >4 billion years ago --------------- Q10) A mineral contains 75% parent isotope and 25% daughter isotope. The half-life of the isotope system is 200 years. When did this mineral crystallize? Give answer in years and only input the number. A: 100 --------------- Q11) The oldest rocks on Earth are ______ and 4.013 billion years old. The oldest minerals on Earth are found in _____ rocks and are 4.4 billion years old. A: Answer 1 - metamorphic Answer 2 - sediment --------------- Q12) Use the figure below to answer parts 1 & 2 Part 1: Order the follow from oldest-1 to youngest-6: A: deformed metamorphic rocks = 1 dike D = 5 sedimentary later C = 4 pluton B = 3 fault F = 6 fault A = 2 Part 2: What type of unconformity is between layer E and layer C? A: disconformity

Mod 7 Participation

Q1) Recrystallization: A: Changes the texture (shape and size of the grains) --------------- Q2) What is the main reason the mineralogy of a rock changes during metamorphism? A: Some minerals are only stable under limited conditions of temperature and pressure, so they change when the conditions change --------------- Q3) Tensional stress is most likely to occur at which type of plate boundary? A: continental rift --------------- Q4) Compressional stress is most likely to occur at which type(s) of plate boundaries: A: collision zone subduction zone --------------- Q5) Which of the compressional stress orientations (red arrows) corresponds to the foliation shown in this rock sample? A: C --------------- Q6) Each of the images below shows a stage in the formation of a metamorphic rock. Select the answer that shows the steps in order from earliest to latest: A: Image C, Image A, Image B --------------- Q7) Metamorphism of sandstone produces _______ , whereas metamorphism of limestone produces ________ . A: Answer 1 - quartzite Answer 2 - marble --------------- Q8) Metamorphism involving hot fluids like water is: A: hydrothermal metamorphism --------------- Q9) Regional metamorphism is common at which of the following plate tectonic settings? A: convergent—collision zones convergent—subduction zones --------------- Q10) Which of the following would you NOT expect to find at a convergent plate boundary? A: Normal faults --------------- Q11) The major types of stress are _______. A: Shear, tension, and compression --------------- Q12) The relationship between stress and strain is: A: Strain is the result of stress --------------- Q13) Faults are examples of what kind of rock deformation? A: Brittle --------------- Q14) For the fault indicated in the figure below, which side is the hanging wall? A: A is the hanging wall --------------- Q15) The image shows more than 8 feet of offset on the Richardson Highway in Alaska that resulted from a magnitude 7.9 earthquake along the Denali Fault in 2002. Notice the Trans Alaska Pipeline in the background. This type of offset suggests that what type of fault motion occurred in this area? A: Right-lateral strike-slip faulting --------------- Q16) Below is a geologic map showing different formations. Each color represents a different formation. The symbols on the map point to the direction the limbs of a fold are pointing. Based on this information, what type of geologic structure are we observing? A: syncline --------------- Q17) Which of the following terms refers to the process of mountain building? A: Orogeny --------------- Q18) Which type of plate boundary is associated with most of the Earth's major mountain belts? A: convergent --------------- Q19) The collision of Africa and North America produced the _______________ Mountains. A: Appalachian --------------- Q20) Mountains of western North America were formed by which of the following (select all that apply): A: Island arc collision Continental Rifting Subduction

Mod 8 Participation

Q1) What does the term uniformitarianism mean? A: We can interpret the processes that formed ancient rock by examining the processes that form similar rock today ----------- Q2) According to the principle of cross-cutting relations, which of the following features in the above cross section is the oldest? A: sedimentary layer F ----------- Q3) According to the principle of cross-cutting relations, which of the following features in the above cross section is the youngest? A: sedimentary layer A ----------- Q4) The principle of lateral continuity says that: A: Sedimentary layers initially formed as continuous expanses of sediment ----------- Q5) Which of the following geologic observations would not necessarily help in working out the sequence of geologic events in an area? A: The feldspar and quartz contents of a granite ----------- Q6) Order the following events from oldest (1) to youngest (7): A: a. Emplacement of granite plutons = 4 b. Deposition of layers 1-7 = 1 c. Emplacement of basalt dike = 6 d. Current land surface erosion = 7 e. Fault = 5 f. Folding of layers 1-7 = 3 g. Emplacement of sill = 2 ----------- Q7) An unconformity in the geologic record always indicates _________. A: There is a gap in the time across the unconformity ----------- Q8) An angular unconformity represents a missing part of the deposition history in an area and we also know: A: That the region has experienced deformation. ----------- Q9) Name this unconformity: A: nonconformity ----------- Q10) What is the advantage to the preservation of a fossil by permineralization over an impression? A: Permineralization may preserve some information on the interior of the organism. ----------- Q11) What is most important concerning whether a fossil is preserved or not? A: Rapid burial keeps the dead organism from being eaten by animals or bacterial decay. ----------- Q12) The principle of fossil succession states that: A: Every fossil species spans only a limited range of rock layers, corresponding to the time period over which it lived. ----------- Q13) How many half-lives have passed if a rock contains 25% parent isotopes and 75% daughter isotopes? A: 2 ----------- Q14) Why are sedimentary rocks more difficult to directly date than igneous or metamorphic rock? A: They are usually composed to sediments of preexisting rock, so any ages obtained represent the age of the rocks that weathered to produce them. ----------- Q15) The half-life of a given radioactive isotope is 100 million years. A mineral specimen contains 2 parent isotopes for every 14 daughter isotopes. Assuming no escape of parent or daughter during decay, how old is the specimen? A: 300 million years ----------- Q16) Carbon dating is best used on _____ samples of _____ origin. Uranium-Lead dating is best used on _____ samples containing the mineral ______. A: Answer 1 - young Answer 2 - organic Answer 3 - old Answer 4 - zircon ----------- Q17) In the figure below, the green unit between A and B is an ash bed that has been dated as 160 m.y. old. Which of the following statements is true based on that? A: Unit B is younger than 160 m.y. �and unit C is older than unit E ----------- Q18) Which of the following are true about the age of the Earth, it's rocks, and it's minerals? (select all that apply) A: The oldest rocks on Earth are metamorphic and 4.013 billion years old because the Hadean was a hot time in Earth's history and any rocks that formed were remelted during the first ~500 million years The oldest minerals on Earth are zircons formed 4.4 billion years ago The age of the Earth (4.56 billion years) is known from dating meteorites and Moon rocks that formed at the same time Earth formed.

Quiz 6: Soils & Sedimentary Rocks

Q1) Which of the following is not a category of sedimentary rocks? A: Mechanical --------------- Q2) Potassium Feldspar (K A l S i3O8) changes to Kaolinite (A l2S i2O5(O H)4 through a process called _________. A: Hydrolysis --------------- Q3) Which of the following examples of cities experience the fast rate of weathering of roads (formation of potholes) in the wintertime? A: A city with nightly average low temperatures of 15 degrees F, and average daytime highs of 40 degrees F. --------------- Q4) True or false, slightly acidic water is necessary for water to chemically erode a rock or material. A: False --------------- Q5)Where would you expect to get the thinnest O-layer in a soil profile? A: In a desert --------------- Q6) What part of the U.S. was most severely affected by the dust bowl? A: Oklahoma, Kansas, and Texas --------------- Q7) Which of the following are examples of sedimentary rock structures that preserve features in the sedimentary record? (select all that apply) A: mudcracks, ripple marks, dinosaur footprints --------------- Q8) The grade of coal increases with: (remember a higher grade of coal means it produces more energy when burned) A: Compaction --------------- Q9) Why does the parent material matter when forming soil? (select all that apply) A: affects the soil's fertility because the parent rock controls the chemical makeup of minerals in a soil, affects the rate of soil formation because the parent material affects the rate of weathering. --------------- Q10) Order the following based on how far they have traveled from their source (assuming all have been transported by liquid water). (1-closest to source; 3-furthest from source) (Think about the CLAST size, roundness, and sorting, NOT the rock as a whole.) A: Answer 1 is 2 Answer 2 is 3 Answer 3 is 1 --------------- Q11) Using the image map below, fill in the following information: 1 - Depending on the local climate, rocks will chemically weather faster or slower. There are three locations, A, B, and C, indicated on the following map. In order of FASTEST to SLOWEST weathering, the correct order is ______________. 2 - We know this because rocks in climates with : ____________ temperatures experience slower chemical weathering, and drier conditions experience slower chemical weathering. A: Answer 1: A, C, B Answer 2: lower Answer 3: drier --------------- Q12) Order the following from 1-largest to 4-smallest sediment size. A: silt - 3 sand - 2 gravel - 1 clay - 4