GEO_103_Exam_1_Key

Name: Version #1 GEO 103 – Semester Exam #1 (each question is worth 1 point out of a possible 25 points) 1) The discovery of the unconformity at Siccar Point by James Hutton was important because: A. It provided a proof of his hypothesis that observations of modern processes could be used to understand the ancient processes that formed the rocks at Siccar Point B. It enabled him to develop the concept of “Deep Time”, which states that the Earth’s rock record accumulates slowly over vast periods in Earth history C. It overturned the conventional wisdom of the time, which stated that all of the events in Earth history had to be explained by fast, catastrophic processes in order to accommodate the Biblical view that the Earth is only about 7000 years old. D. All of the above 2) The fact that we can make measurements of processes in the laboratory and use them to explain features of ancient rocks, even in cases where the experimental conditions no longer exist at the surface of the Earth today, is a statement of which principle? A. Catastrophism B. Uniformitarianism C. Actualism D. Steno’s Principles 3) Using the field sketch at right, and your knowledge of Steno’s Principles, determine the order in which the black, white and gray rocks were formed, from oldest to youngest: A. Gray, black, white B. Black, white, gray C. White, gray, black D. Gray, white, black 4) On the Geological Timescale below, which period lasted from 2.5 billion years ago to 545 million years ago? A. Proterozoic Eon B. Phanerozoic Eon C. The Precambrian D. The Cenozoic Era 5) The figure below actually misrepresents a key aspect of the Geological Timescale. Can you tell what is wrong with it? A. The Phanerozoic Eon is not divided into the correct number of Eras B. The Hadean and the Archean are in the wrong order C. This geological timescale makes the Phanerozoic look longer than the Precambrian D. T here’s nothing wrong with this geological timescale 4.5 Billion Years ago Today

6) In the field sketch on the previous page, if the gray and white rocks are sedimentary rocks, and the black rock is an intrusive igneous rock, what effect would the black rock have on the white and gray rocks it is intruding into? What texture should the black rock have? A. It could cause the white and gray rocks to recrystallize with a non-foliated texture because of contact metamorphism; the black rock should have a coarse-grained texture. B. The black rock would cause platy minerals in the white and gray rocks to align themselves in parallel layers because of the pressure it exerts on them; the black rock should be glassy. C. None of the above. 7) How does the origin of sedimentary clay particles derived from a body of igneous rock differ from the origin of quartz sand grains that are derived from the same body of igneous rock? A. Clay minerals are mainly derived from chemical weathering of igneous rock, whereas quartz grains are mainly derived from physical weathering of the same body of rock B. Quartz is mainly derived from chemical weathering of igneous rock, whereas clay minerals are mainly derived from physical weathering of the same body of rock C. There is no difference in their origin – both of them are part of the original igneous rock that cooled from a magma and were then physically weathered from the rock 8) A sandstone outcrop made entirely of well-rounded, 1mm diameter quartz grains with a cross- bedded structure would be considered what type of sedimentary rock? On their own, do these textural features allow you to determine if the sand was transported by wind vs. water? A. Biochemical sedimentary rock. Yes. B. Detrital sedimentary rock. No. C. Chemical sedimentary rock. No. 9) You encounter a large block of volcanic glass, called obsidian, while mapping rock outcrops on the island of Hawai’i . True or False – this rock probably formed by rapid cooling of lava at the surface of the Earth, possibly in contact with water A. True B. False 10) In what ways are the Earth’s Water Cycle and Rock Cycle related to each other? A. The water cycle delivers water to mountainous areas, providing the main chemical and physical agent of weathering and erosion that produces sediment B. Water is delivered to the Earth’s mantle from the oceans at subduction zones, allowing the mantle to melt, forming magma that cools to become igneous rock C. Water participates in chemical reactions that result in the formation of new minerals during high temperature and pressure metamorphism, such as: Al 2 SiO 5 + 3SiO 2 + H 2 O => Al 2 Si 4 O 10 (OH) 2 D. All of the above

16) When we say that a certain species of protist is a producer , what do we mean? A. That it is a photosynthetic, plant-like protist B. That is an animal-like protist that derives energy from organic matter produced by other organisms C. That it forms an important component of the base of an ecosystem’s food web D. A and C are both correct 17) The Great South Bay on Long Island experiences frequent algae blooms that are fueled by the runoff of excess nitrogen and phosphorous from fertilizer and septic systems into the bay. As the algae die, their decomposition consumes the O 2 in the water, killing off fish that live in the bay, who need it to breath. This indicates that O 2 is a limiting factor for algae living in the bay. A. True B. False 18) Which of the following statements does not describe a way that the Coriolis Effect influences the Earth’s ocean and atmosphere system A. It causes shallow ocean currents to rotate in gyres that drive ocean water towards the western side of each ocean basin on the Earth B. It is responsible for the generation of the major wind currents in the northern and southern hemispheres, and creates a belt of dry, desert climates at 30 o latitude C. It is responsible for the generation of salty, cold, dense deep-water ocean currents that flow from the poles towards the equator D. It is caused by the rotation of the Earth, which imparts angular momentum to moving masses of air and water at the Earth’s surface 19) Which of the following shows terrestrial climate zones in the correct equator to pole order: A. Desert, Tropics, Temperate Forest, Savannah and Grassland, Polar, Tundra B. Tropics, Desert, Savannah and Grassland, Temperate Forest, Tundra, Polar C. Sub-Antarctic, Subarctic, Tropical, Subtropical, Transitional 20) Imagine you are taking a summer driving trip across the state of Washington, in the US Pacific Northwest. You start in the cool, coastal climate of Seattle, and drive east across the snow- capped Cascades volcanic mountain range, which are covered in abundant coniferous evergreen trees. As you cross over to the east side of the Cascades and drop in elevation towards the city of Yakima, the climate turns hot, arid, and dry and the landscape only has shrubs and grasses, with no trees. What caused this major change in climate and vegetation between the west and east sides of Washington state? A. The winter monsoon, which produces cold, high pressure air currents that prevent moist air rising off the Pacific Ocean from reaching the land B. The trade winds, which are located at ~30 north latitude and are responsible for creating the Earth’s great deserts C. A rain shadow created by the Cascades mountain range D. None of the above

21) Varves are made of layers of alternating coarse sand/silt and fine- grained mud. How many years did it take for the column of varved sediment shown in the upper part of the image to form? What environment does the dropstone in the lower part of the image tell you that the column of sediment formed in? A. 18 years; a glacial lake environment B. 9 years; a glacial lake environment C. 18 years; a desert playa lake environment D. 9 years; a desert playa lake environment 22) The Earth is ____ years old and for the first _____ years, all life on Earth consisted of ________. A. 4.5 billion; half billion; unknown, but likely prokaryotic, organisms B. 4.5 billion; half billion; multi-cellular plants and animals C. 4.5 billion; 3-4 billion; single celled prokaryotes D. A and C could both be true 23) An important assumption made in cladistics research is that A. Not all species within a taxonomic group can be traced to a common ancestor B. More species will go extinct than will originate over a given period of time C. When two groups share a particular biological trait, both groups inherited the trait from a common ancestor D. Species are defined by their ability to interbreed with each other 24) Long Island has two long ridges that run east to west across the center of the island and along its north shore. These ridges are composed of unsorted, heterogenous sediment with particle sizes ranging from clay to boulders. To the south of the ridges are broad plains of sand and isolated lakes, like Lake Ronkonkoma. What are these two ridges and how did they form? A. Alluvial fans formed by flash floods coming from the mountainous areas of Connecticut B. Moraines made of till formed by the advance of glacial ice sheets across the continents C. Beach dune deposits formed by prevailing westerly winds that blow across Long Island D. Deposits of marine sediment that were washed onto Long Island by hurricanes 25) You are mapping outcrops of extremely well-sorted, well-rounded, cross bedded quartz sandstone that contains bivalve shell fragments and broken up calcite spicules. The cross beds look like the image below. From these features you can conclude that the sandstone: A. Was deposited in a desert dune in which the winds were blowing from east to west B. Was deposited in a coastal marine environment in which wind or water currents were blowing from west to east C. Was deposited in a beach dune in which the winds were blowing from east to west West East