GEOL 1550 Exam 1 (Ch 1-4)
Compared to continental crust, oceanic crust is generally __________. A) thinner, denser, darker in color, and at lower elevations B) thicker, less dense, lighter in color, and higher in elevation C) thicker, less dense, darker in color, and lower in elevation D) thinner, less dense, lighter in color, and higher in elevation E) thicker, denser, darker in color, and at lower elevations
A
Compared to the rest of the planet, an unusually high concentration of hot spots and rifting is located on the continent of Africa. A likely explanation for this is that __________. A) the African Plate is essentially stationary with respect to Earth's interior and the thick continental crust acts as a "heat blanket" B) the thick continental crust acts as a "heat blanket" and a large portion of Africa is located near the equator C) mantle plumes do not occur at divergent plate boundaries, and Africa has no divergent plate boundaries D) a large portion of Africa is located near the equator Africa is just very large
A
Consider the geologic fate of the following seamounts and islands in the Hawaiian Island-Emperor Seamount chain. Assuming conditions remain favorable for coral growth, which would most likely be the next to form an atoll? A) Kauai B) Loihi C) Hawaii D) Maui E) Oahu
A
Iceland is located on what type of plate boundary? A) Divergent B) Transform C) Continental/continental convergent D) Oceanic/continental E) Oceanic/oceanic convergent
A
Marine sediment with more than 30% biogenous material is called __________. A) ooze B) clathrate C) mud D) oolite E) slime
A
Numerous small, shallow earthquakes tend to occur at __________. A) divergent plate boundaries B) continental/continental convergent plate boundaries C) oceanic/oceanic convergent plate boundaries D) oceanic/continental convergent plate boundaries E) transform plate boundaries
A
Of the following statements about the age of the ocean crust, which one is true? Select only one answer. A) The oldest ocean crust is about 200 million years old and is located near an ocean trench. B) The oldest ocean crust is about 200 million years old and is located near the mid-ocean ridge. C) The oldest ocean crust is about 2 million years old and is located near an ocean trench. D) The oldest ocean crust is about 2 million years old and is located near the mid-ocean ridge. E) The oldest ocean crust is about 4.5 billion years old and is located near the edge of a continent.
A
The most abundant mineral in lithogenous sediments is __________. A) quartz B) halite C) calcite D) aragonite E) gypsum
A
What do all plate boundaries have in common? Select only one answer. A) They are all associated with zones of earthquakes. B) They are all located along the edges of continents. C) They occur entirely within the middle of continents. D) They occur only on the ocean floor. E) They are all associated with an abundance of volcanic activity.
A
Which of the following statements is supported by the nebular hypothesis regarding the formation of our solar system? A) The Sun became a star when its temperature and density became so great that nuclear fusion began. B) The initial atmospheres of Earth and other planets close to the Sun were rich in ammonia and carbon dioxide. C) The Sun and the rest of the solar system were formed about one billion years ago. D) The solar system was formed by the expansion of a relatively small cloud of gas and space dust. E) The moon is believed to have been a protoplanet that passed close to Earth and was captured by its gravitational field.
A
You add sand, silt, and clay to a jar of water, shake the jar vigorously, and allow the sediment to settle. The resulting sediment will most closely resemble that of a(n) __________. A) continental rise B) tropical reef or bank C) abyssal plain D) abyssal hills province E) mid-ocean ridge
A
Of the following sediments, which one(s) is/are considered biogenous? Choose all that apply. A) tests of foraminifers B) radiolarian ooze C) manganese nodules D) coatings of metal sulfides near black smokers E) abyssal clay F) black volcanic beach sand
A B
Of the following statements about ocean crust, which is/are true? Choose all that apply. A) Ocean crust is created at the mid-ocean ridge. B) Ocean crust is destroyed at deep-sea trenches. C) Ocean crust is destroyed at the mid-ocean ridge. D) Ocean crust is created at deep-sea trenches. E) Ocean crust is destroyed at transform faults.
A B
Why does the sea floor have a striped pattern of magnetic anomalies that is symmetric with respect to the mid-ocean ridge? Choose all that apply. A) The ocean floor is spreading apart and new sea floor is forming. B) The polarity of Earth's magnetic field experiences reversals. C) The igneous rock of the ocean floor preserves Earth's existing magnetic field as the rock cools. D) Polar reversals cause existing ocean crust to remagnetize. E) Marine organisms that live on the sea floor have caused this pattern.
A B C
Of the following statements about Earth's hypsographic curve, which is/are true? Choose all that apply. A) The hypsographic curve shows the percentage of Earth's surface area that is covered by ocean waters. B) The hypsographic curve shows that a majority of the exposed land is below 1 kilometer in elevation. C) The hypsographic curve shows that the average depth of the ocean is about four times the average height of the continents. D) The hypsographic curve shows that a majority of the ocean floor is more than 4 kilometers deep. E) The hypsographic curve shows that the volume of water in the oceans is greater than the volume of water in lakes and glaciers.
A B C D
Of the following statements about turbidity currents, which is/are true? Choose all that apply. A) Turbidity currents are episodic events (they don't occur all the time, but only every so often, like a flash flood). B) Turbidity currents move sediment down the continental shelf and the continental slope to be deposited on the continental rise. C) The material carried by turbidity currents is what builds deep-sea fans. D) Turbidity currents are highly erosive and carve submarine canyons. E) Turbidity currents are composed of low-density water that sinks and follows the shape of the seafloor.
A B C D
Marine sediments provide valuable clues about which of the following Earth history events? Choose all that apply. A) movement of the ocean floor B) the ancient geographical locations of ocean basins C) the climate on Earth millions of years ago D) previous ocean circulation patterns E) past catastrophes, such as major extinction events
A B C D E
Which of the following ideas support our current scientific understanding of the development of life on Earth? Choose all that apply. A) Primitive life likely existed without the need for oxygen. B) The "prebiotic soup" of the primitive oceans provided favorable conditions for life to develop. C) As life evolved it significantly changed Earth's environment. D) The most primitive life on Earth needed sunlight to metabolize food. E) Early organisms evolved into more-complex organisms over geologic time.
A B C E
Based on the concept of isostatic adjustment, which of the following would result in the uplift of Earth's surface? Choose all that apply. A) lithosphere that was thickened by mountain building B) lithosphere that was made to be less dense C) lithosphere that was weighed down by glacial ice D) lithosphere that was heated by hot asthenosphere E) lithosphere that gets a large amount of additional mass added on top of it
A B D E
Of the following techniques, which one(s) can be used to map the sea floor? Choose all that apply. A) recording many depths using a long cable B) direct visitation of the sea floor C) measuring seawater clarity D) using satellites to measure the sea surface E) sending sound through water (sonar)
A B D E
What processes influence the shape and features of continental shelves? Choose all that apply. A) major climate changes, such as ice ages B) trench formation at convergent boundaries C) the creation of pillow lavas along the mid-ocean ridge D) large fluctuations in sea level over geologic time E) tectonic activity produced by offshore faults
A B D E
Of the following events, which occurred during the Age of Discovery in Europe? Choose all that apply. A) Ferdinand Magellan's crew completed the first circumnavigation of the globe. B) Captain James Cook explored the Pacific, tried to reach the "Southern Land," and searched for the fabled "northwest passage." C) John Harrison solved the "longitude problem" by inventing an accurate timepiece (watch). D) Christopher Columbus made several trips across the Atlantic and discovered a "new world." E) The Vikings actively explored the North Atlantic Ocean and set up colonies in Iceland, Greenland, and North America (Vinland). F) Thor Heyerdahl sailed the balsa raft Kon Tiki to Polynesia to help establish a link of ancient peoples.
A C
Of the following statements about the internal structure of Earth, which is/are true? Choose all that apply. A) The mesosphere and the asthenosphere have the same chemical composition. B) The composition of the lithosphere is uniform throughout. C) The magnesium-silicate rocks of Earth's mantle exist in both solid and molten form. D) The asthenosphere is composed of basalt and granite. E) The liquid outer core is composed of different metals than the solid inner core.
A C
Which of the following are microscopic, single-celled floating algae that accumulate to form biogenous sediment? Choose all that apply. A) Coccolithophores B) Tektites C) Diatoms D) Foraminifers E) Radiolarians
A C
Of the following statements about Nemataths and volcanic arcs, which is/are true? Choose all that apply. A) Nemataths and volcanic arcs are both the result of volcanic activity. B) The age of the volcanoes progressively decreases as you move from one end of a volcanic arc to the other. C) In a volcanic arc, any of the volcanoes can be active at any time. D) Volcanic arcs are associated with convergent plate boundaries. E) Volcanic arcs are created at hotspots.
A C D
Of the following statements about Earth's magnetic field, which is/are true? Choose all that apply. A) The lines of the magnetic force are perpendicular relative to Earth's surface at the magnetic north pole. B) Magnetic north is at the same point on Earth as the geographic north pole. C) The lines of the magnetic force are perpendicular relative to Earth's surface at the magnetic south pole. D) The lines of the magnetic force are parallel with Earth's surface at the equator. E) The magnetic north pole may reverse so that it is located near the geographic south pole.
A C D E
The majority of ocean trenches are associated with ___________. Choose all that apply. A) the Pacific Ring of Fire B) the mid-ocean ridge C) volcanic arcs and active continental margins D) subduction zones and associated faults E) narrow or no continental shelves F) very deep ocean water depths
A C D E F
Of the following statements related to the formation of a density-stratified Earth, which is/are true? Choose all that apply. A) The layer of Earth with the greatest density is located at the deepest depth beneath Earth's surface. B) The thickest layer of Earth has the greatest density. C) Rocky material of the mantle is less dense than the liquid outer core. D) Molten material will rise if it is less dense than the surrounding material. E) Solid materials will always sink beneath fluid materials.
A D E
Which of the following statements correctly interpret the environmental conditions associated with types of biogenous deposits? Choose all that apply. A) Diatomaceous ooze on the sea floor indicates cool surface water above. B) Radiolarian ooze on the sea floor suggests warm surface water associated with the mid-ocean ridge. C) Calcareous ooze on the sea floor means there is an area of upwelling above. D) Foraminifer ooze on the sea floor means warm surface water above. E) Coccolith ooze on the sea floor indicates the water is shallower than 4000 meters.
A D E
Which of the following organisms are responsible for the creation of siliceous ooze? Choose all that apply. A) Radiolarians B) Foraminifers C) Stromatolites D) Coccolithophores E) Diatoms
A E
Earthquakes can occur only in the __________. A) crust B) lithosphere C) asthenosphere D) mesosphere E) outer core
B
From smallest to largest, which list of sediment particle sizes is in the correct order? A) clay, sand, silt, pebbles B) clay, silt, sand, pebbles C) sand, silt, clay, pebbles D) pebbles, sand, silt, clay E) silt, clay, sand, pebbles
B
Graded bedding provides evidence that __________. A) turbidity currents carry large particles farther than smaller, lighter particles B) large, heavy particles settle out first as current velocity decreases C) submarine canyons were cut by streams during ice ages when the continental shelves were above sea level D) glaciers deposited sediments on continental shelves E) turbidity currents are triggered by earthquakes
B
In science, which one of the following would be considered an observation? Select only one answer. A) Waves are usually caused by a distant storm. B) Waves are seen to approach the beach at an angle. C) Waves lose little energy as they travel across the ocean. D) Waves are the result of a disturbance (release of energy) somewhere in the ocean. E) Waves transfer wind energy from the surface to deeper water.
B
Measurement of ocean floor bathymetry from satellites relies on ___________. Select only one answer. A) calculations of how much water versus rock there is at any ocean location B) sea surface elevation, which varies depending on the shape of the underlying seafloor C) density differences of ocean waters D) water temperature, which is higher in areas of shallow ocean waters and can easily be detected by satellites E) the amount of time it takes for a radar pulse to travel from the satellite to the seafloor
B
Most large ocean floor features owe their origins to _________. A) biological activity B) plate tectonic processes C) extreme pressure at depth D) erosion and weathering E) ocean current activity
B
Nearly all oceanic islands are __________. A) parts of volcanic island arcs B) volcanic in origin C) parts of continents D) separated from continents formed at hot spots as lithospheric plates pass over mantle plumes E) formed at high-standing areas of mid-ocean ridges
B
The measurement of ocean depth and the charting of seafloor topography is called __________. A) tomography B) bathymetry C) navigation D) cartography E) hydrology
B
Of the following types of lithogenous sediment, which one(s) would you expect to find very far from the location of origin? Choose all that apply. A) Pebbles B) Volcanic ash C) Quartz silt D) Boulders E) Quartz granules
B C
Of the following, which energy resource(s) can be extracted from marine sediments? Choose all that apply. A) Phosphorites B) Gas hydrates C) Petroleum D) Halite E) Manganese nodules
B C
Which of the following lines of evidence did Alfred Wegener use to support the concept of drifting continents? Choose all that apply. A) the composition of meteors from outer space B) evidence of glaciers in areas that are now tropical C) the pattern of similar mountain belts on different continents D) the way the shapes of the continents fit together like pieces of a jigsaw puzzle E) the distribution of species of fossils
B C D E
Of the following statements about Earth's crust, which is/are true? Choose all that apply. A) Continental crust is made mostly of basalt. B) Continental crust and oceanic crust are both composed of igneous rocks. C) Continental crust is made of rock that is relatively light in color. D) Continental crust is less dense than oceanic crust. E) Continental crust is much thinner than oceanic crust.
B C E
Which of the following feature(s) is/are associated with the mid-ocean ridge? Choose all that apply. A) a trench B) basalt volcanism and pillow lavas C) volcanoes D) thick layers of sediment E) hydrothermal vents F) a central rift valley
B C E F
Of the following statements about density stratification, which is/are true? Choose all that apply. A) Density stratification caused the oxygen crisis on Earth. B) Outgassing is a direct result of density stratification. C) The time periods of the geological time scale are based on events caused by density stratification. D) The origin of Earth's oceans and atmosphere are a result of density stratification. E) Density stratification has caused Earth's internal structure to be layered. F) Density stratification has caused the highest-density material to be found at Earth's core.
B D E F
Of the following statements about the asthenosphere, which is/are true? Choose all that apply. A) The asthenosphere is composed of solid rocks associated with the rigid mantle. B) The asthenosphere is a highly viscous layer located beneath the lithosphere. C) The asthenosphere is composed of liquid molten rock. D) The asthenosphere consists partially of crust and partially of mantle. E) The asthenosphere is very hot and contains areas of partially molten rock. F) The asthenosphere will fracture under extreme pressure.
B E
********Trenches are typically associated with ________. A) fracture zones B) passive continental margins C) convergent continental margins D) transform continental margins E) abyssal hills
C
Evidence shows that periodic reversals of Earth's magnetic field have resulted in __________. A) seafloor spreading B) mass extinction of life-forms C) a symmetrical pattern of normal and reverse magnetization in ocean crustal rocks D) interruption of Earth's gravitational field E) apparent polar wandering
C
If the rate and direction of plate movement remain the same for the next 50 million years, an accurate prediction would then be: A) Formation of a land bridge between Australia and Antarctica B) Suturing of the Atlantic Ocean C) Accretion of the California Terrane onto Alaska D) Rifting of the Eurasian plate to form a juvenile ocean E) Subsidence of the Himalayan Mountains
C
In comparison with other ocean basins, major sedimentary features such as continental rises and abyssal plains are relatively rare in the Pacific. The primary reason for their scarcity in the Pacific is that __________. A) turbidity currents are rare in the Pacific, so little sediment is carried down the continental slopes B) rivers do not carry much sediment into the Pacific C) sediment is trapped within the trenches of the convergent plate boundaries D) ringing the Pacific the numerous volcanoes of the Pacific rim and islands prevent normal sedimentation E) the Pacific Ocean is too large for those features to form
C
Neritic sediments are most likely to be composed of __________. A) red clay B) biogenic ooze C) sand, silt, and gravel D) basalt fragments and metallic sulfides E) halite, gypsum, and anhydrite
C
Of the following statements about sea floor magnetic anomalies, which is true? Select only one answer. A) They are oriented perpendicular to deep sea trenches. B) They are oriented parallel to all mountain ranges. C) They are oriented parallel to the mid-ocean ridge. D) They are oriented perpendicular to all mountain ranges. E) They are oriented perpendicular to the mid-ocean ridge.
C
Oozes are uncommon on continental margins because __________. A) relatively few marine organisms live in the waters over the continental margins B) biogenous material dissolves faster than it accumulates C )the biogenous component tends to be overwhelmed by the amount of lithogenous material derived from the nearby continent D )the abundance of hydrogenous material keeps the percentage of biogenous material too low E) very little sediment accumulates on continental margins
C
Sediments with all grains of about the same size are classified as __________. A) lithogenous turbidites B) well rounded C) well sorted D) neritic
C
The explorer who advanced oceanography by introducing systematic soundings, or depth measurements, was __________. A) Christopher Columbus B) James Cameron C) James Cook D) Leif Erikson E) Jacques Piccard
C
The greatest proportion of Earth's surface lies in this elevation/depth interval. 0 - 1,000 m above sea level 3,000 - 4,000 m below sea level 4,000 - 5,000 m below sea level 1,000 - 2,000 m above sea level 5,000 - 6,000 m below sea level
C
The important contribution to navigation made by Eratosthenes in the third century BC was __________. A) discovery of a trade route from Europe around the African continent to India B) the introduction of latitude and longitude lines on maps of the world C) a reasonably accurate calculation of the circumference of our planet D) exploration outside the Mediterranean and into the North Atlantic Ocean E) devising a means of fixing longitude while at sea
C
The largest geographic feature on the surface of Planet Earth is __________. A) Africa B) the Atlantic Ocean C) the Pacific Ocean D) Eurasia E) the Antarctic ice cap F) The Pacific Ocean
C
The lithosphere consists of Earth's __________. A) upper mantle and hydrosphere B) lower mantle crust and ocean C) crust and uppermost mantle D) outer core
C
Which of the following would best describe the principal goal of science? Select only one answer. A) to explain why the world and the laws of nature exist B) to develop theories that help scientists determine the truth C) to explain the causes and effects of observable natural phenomena D) to allow scientists to test their hypotheses with experiments to determine what happened in the past
C
You take a sediment sample from the ocean floor at a depth of 5500 m. The area has low biological productivity and the CCD is at 4500 m depth. Your sample will probably consist of __________. A) sand B) coral C) clay D) siliceous ooze E) calcareous ooze
C
Of the following items, which is/are associated with a passive continental margin? Choose all that apply. A) volcanic eruptions and pillow lavas B) an abundance of earthquake activity C) a wide continental shelf D) a continental rise E) a deep-ocean trench
C D
Which of the following statements accurately describes a segment of the mid-ocean ridge spreading at a rate of 3 centimeters per year? Choose all that apply. A) It would be classified as an oceanic rise. B) It would create a broad, swollen region symmetrical to the axis of the ridge. C) It would be classified as an oceanic ridge. D) It would have a prominent and deep rift valley. E) It would have few, widely spaced volcanoes associated with it.
C D
In which of the following environments would you expect lithogenous sediment to be the dominant sediment type? Choose all that apply. A) near a black smoker B) a coral reef C) a sandy beach D) the abyssal plains E) at the base of the continental slope
C D E
Of the following statements about mapping the ocean floor, which is/are true? Choose all that apply. A) Nearly 80% of the ocean floor has been accurately mapped using sonar from ships. B) Satellites can be used to determine the structure and composition of the seafloor. C) Measurements of sea surface elevation by satellites are used to produce maps of the seafloor. D) Multibeam surveys from ships produce very detailed maps of the seafloor. E) Only about 20% of the seafloor has been accurately mapped in detail.
C D E
Of the following sediments, which one(s) is/are considered hydrogenous? Choose all that apply. A) black volcanic beach sand B) radiolarian ooze C) manganese nodules D) tests of foraminifers E) abyssal clay F) coatings of metal sulfides near black smokers
C F
A ship's fathometer (an echo sounder) transmits a sound pulse and records the return of an echo 7.4 seconds later. If the speed of sound in water is 1,500 m/second, what is the water depth in meters? A) 7,400 meters B) 11,100 meters C) 4,550 meters D) 5,550 meters E) 3,000 meters
D
A trench and a chain of volcanoes known generally as a volcanic arc are always present where there is __________. A) subduction B) a divergent plate boundary C) a transform plate boundary D) a convergent plate boundary E) a hot spot
D
According to the Geologic Time Scale, which selection lists the correct order of coexistence, from earliest to latest? A) Trilobites and amphibians, insects and dinosaurs, flowering plants and fishes, dinosaurs and birds, humans and reptiles B) Insects and dinosaurs, trilobites and amphibians, dinosaurs and birds, flowering plants and fishes, humans and reptiles C) Trilobites and amphibians, dinosaurs and birds, insects and dinosaurs, flowering plants and fishes, humans and reptiles D) Trilobites and amphibians, insects and dinosaurs, dinosaurs and birds, flowering plants and fishes, humans and reptiles E) Trilobites and amphibians, insects and dinosaurs, dinosaurs and birds, humans and reptiles, flowering plants and fishes
D
Earth's current atmosphere supports animal life because __________. A) the oceans have provided water vapor B) bacterial action has produced essential methane C) plant photosynthesis has provided carbon dioxide D) plant photosynthesis provides oxygen that is critical for aerobic respiration E) volcanic outgassing produced essential nitrogen and argon
D
Stanley Miller's famous experiment demonstrated that __________. A) the earliest organisms lived in volcanoes B) all the required factors have been identified for the production of living organisms C) living organisms can be produced by lightning strikes D) organic molecules could be produced from the mixture of gases comprising Earth's early atmosphere E) Earth's early atmosphere was rich in CO2, ammonia, and hydrogen
D
The water in Earth's oceans came __________. A) completely from comets colliding with Earth B) from the melting of polar icecaps that formed when protoplanet Earth first cooled C) completely from volcanic outgassing D) mostly from volcanic outgassing and partly from comets E) from the condensation of water vapor in Earth's initial atmosphere
D
Which of the following is an example of a nematath? Iceland Great Barrier Reef Mariana Islands Hawaiian Islands-Emperor Seamount Chain Aleutian Islands
D
Which of the following is the main reason that Earth has a magnetic field? Select only one answer. A) Convection of the silicate materials in the asthenosphere generates a magnetic field. B) The solid inner core spins rapidly in the opposite direction as Earth rotates. C) The solid iron-nickel inner core spins rapidly in the same direction as Earth, but much faster. D) Convection in the liquid iron-nickel outer core generates a magnetic field. E) The Sun has such a powerful magnetic field that it creates a magnetic field on Earth.
D
Which of the following conditions allows for calcareous ooze to exist beneath the CCD? Select only one answer. A) The dissolved calcium carbonate precipitates upon contact with the sea floor. B) The deposit is mixed with hydrogenous sediment. C) The calcareous ooze accumulates faster than it dissolves. D) A layer of clay buries the ooze before the sea floor subsides. E) Conditions of high salinity are present.
D)
An oceanographic vessel is mapping a section of the ocean floor stretching for tens of miles in all directions. The seafloor is extremely flat, with a slope of less than one degree, and the water depth is about 4,500 meters. The area being mapped is most likely a(n) __________. A) continental rise B) continental shelf C) continental slope D) continental borderland E) abyssal plain
E
Salt beds of the U.S. Gulf Coast are __________. A) cosmogenous sediments B) neritic sediments C) lithogenous sediments D) biogenous sediments E) hydrogenous sediments
E
Sediment samples from deep beneath the ocean floor are recovered by __________. A) dredging B) grab sampling C) instrumented probes D) gravity coring E) rotary drilling
E
Sediments deposited by the process of suspension settling produce the majority of sediment found on ___________. Select only one answer. A) the continental shelf B) the continental slope and rise C) submarine fans D) shallow islands in tropical seas E) abyssal plains
E
The flat top of a guyot or tablemount in deep water is evidence that __________. A) burrowing organisms have destroyed the peak of the seamount B) the seamount has been submerged by rising sea level that resulted from global climate change C) the seamount is an extinct volcano with the crater filled by a solidified lava lake D) the seamount is an erosional remnant of a flat abyssal plain E) the seamount was once at the surface of the ocean but is now submerged due to plate movement and erosion when it was near sea level
E
Where a mid-ocean ridge is offset, the linear feature connecting and between the crests of the ridge segments is called a __________. A) central rift valley B) seismic fissure C) hydrothermal vent D) fracture zone E) transform fault
E