OCE 1001 FSU Ch. 2
Which of the following tectonic plates are oceanic? Choose all that apply. View Available Hint(s) African Plate Nazca Plate Eurasian Plate North American Plate Pacific Plate
-Nazca plate -Pacific plate
Climate distribution on Earth is primarily controlled by: longitude. plants and animals that live in an area. Earth's geologic history. presence or absence of glacial debris. latitude.
latitude
Complete this statement: Divergence is to moving away as convergence is to _______. moving under moving side-by-side moving toward moving over
moving toward
Which of the following is an example of a continental-continental divergent plate boundary? Red Sea Mendocino Fault Himalaya Mountains Andes Mountains San Andreas Fault
Red Sea
What is the relationship between the crust and the lithosphere? The lithosphere is a special type of crust. The crust is a special type of lithosphere. The crust is part of the lithosphere. The lithosphere is part of the crust.
The crust is part of the lithosphere.
What was Pangea? a supercontinent that formed 100 million years ago a supercontinent that formed 600 million years ago a supercontinent that formed 450 million years ago a supercontinent that formed 300 million years ago
a supercontinent that formed 300 million years ago
Evidence shows that periodic reversals of Earth's magnetic field have resulted in __________. View Available Hint(s) -interruption of Earth's gravitational field -mass extinction of life-forms -apparent polar wandering -seafloor spreading -a symmetrical pattern of normal and reverse magnetization in ocean crustal rocks
a symmetrical pattern of normal and reverse magnetization in ocean crustal rocks
Which of the following is characteristic of oceanic-continental convergent plate boundaries? andesitic volcanoes mid-ocean ridges volcanic island arcs fracture zones hot spots
andesitic volcanoes
Where are tectonic plates located? at Earth's surface just under Earth's surface below Earth's surface, in the upper mantle below Earth's surface, near the core
at Earth's surface
Where do most earthquakes occur? View Available Hint(s) at plate boundaries at the bottom of the ocean on the continents they are evenly distributed all over the world in the middle of the plates
at plate boundaries
Where do magnetic field lines exit the Earth today? at the equator at the South Pole at the North Pole
at the south pole
Which geologic features are associated with divergent boundaries? mid-ocean hot spots and continental rift valleys mid-ocean ridges and continental rift valleys mid-ocean hot spots and ocean trenches mid-ocean ridges and ocean trenches
mid-ocean ridges and continental rift valleys
The study of historical changes of continental shapes and positions is called: paleomagnetism. sedimentology. paleoclimatology. paleogeography.
paleogeography
Sea floor spreading along the axis of an oceanic ridge results in symmetrical patterns of all of the following EXCEPT ______________. View Available Hint(s) the flow of heat through the crust the location of subduction zones the depth of the sea floor the paleomagnetic record the age of the sea floor
the location of subduction zones
Earth's magnetic field is similar to which of the following? the gravitational field of Earth the magnetic field of a bar magnet the magnetic field of a horseshoe magnet the magnetic field of Mars
the magnetic field of a bar magnet
Which of the following is characteristic of oceanic-oceanic convergent plate boundaries? mid-ocean ridges volcanic island arcs fracture zones hot spots
volcanic island arcs
To find the largest area of the ocean with the oldest ocean crust, you should go to the ________. eastern Pacific northern Atlantic southern Ocean near Australia western Pacific
western Pacific
Tectonic plates move about as fast as ________. a snail crawls your fingernails grow a child crawls a river flows grass grows in the summer
your fingernails grow
Which process causes the surface geography of Earth to change over time? rock erosion volcanic eruptions plate tectonics meteor impacts
plate tectonics
What happens when an oceanic plate meets another oceanic plate? View Available Hint(s) The two plates slide past each other. The two plates are forced upward, and a large mountain range is formed. Both plates are subducted. The younger plate will be subducted. The older, colder oceanic plate is subducted.
the older, colder oceanic plate is subducted
Why didn't India subduct under Asia? The two continents have different mass. The two continents have similar densities. The two continents have different densities. The two continents have similar mass.
the two continents have similar densities
Of the following statements about sea floor magnetic anomalies, which is true? Select only one answer. View Available Hint(s) They are oriented parallel to the mid-ocean ridge. They are oriented perpendicular to all mountain ranges. They are oriented perpendicular to deep sea trenches. They are oriented perpendicular to the mid-ocean ridge. They are oriented parallel to all mountain ranges.
they are oriented parallel to the mid-ocean ridge
Where would the north end of a magnet point during a time of reverse polarity? toward the magnetic north pole toward the magnetic south pole toward the geographic South Pole toward the geographic North Pole
toward the magnetic south pole
Which plate boundary is NOT associated with volcanic eruptions? convergent divergent converse transform
transform
Which of the following is characteristic of continental-continental convergent plate boundaries? uplifted mountain ranges hot spots volcanic island arcs mid-ocean ridges
uplifted mountain ranges
Based on paleogeographic records, _____________. View Available Hint(s) -the continents came together as Pangaea before North America was located at the equator -the North Atlantic opened before North America was located at the equator -India separated from Antarctica before North America was located at the equator -India separated from Antarctica before the continents came together as Pangaea -the North Atlantic opened before India separated from Antarctica
the North Atlantic opened before India separated from Antarctica
What is the relationship between the crust and lithosphere? The crust is a special type of lithosphere. The lithosphere is part of the crust. The crust is part of the lithosphere. The lithosphere is a special type of crust.
the crust is part of the lithosphere
Which of the following statements about earthquakes with magnitude greater than 4.0 is most accurate? -Earthquakes with magnitude greater than 4.0 occur in a pattern than correlates loosely with plate boundaries. -Earthquakes with magnitude greater than 4.0 occur in a pattern than correlates closely with plate boundaries. -Earthquakes with magnitude greater than 4.0 occur in a pattern than correlates closely with hot spots. -Earthquakes with magnitude greater than 4.0 occur in a pattern than correlates loosely with hot spots.
-Earthquakes with magnitude greater than 4.0 occur in a pattern than correlates closely with plate boundaries.
Which geographic examples below result(s) from ocean-ocean convergence? Choose all that apply. View Available Hint(s) The Himalayas Andes Mountains Marianas Trench Aleutian Islands Japan
-Marianas Trench -Aleutian Islands -Japan
Of the following statements about Earth's magnetic field, which is/are true? Choose all that apply. View Available Hint(s) -The lines of the magnetic force are perpendicular relative to Earth's surface at the magnetic south pole. -The lines of the magnetic force are parallel with Earth's surface at the equator. -Magnetic north is at the same point on Earth as the geographic north pole. -The magnetic north pole may reverse so that it is located near the geographic south pole. -The lines of the magnetic force are perpendicular relative to Earth's surface at the magnetic north pole.
-The lines of the magnetic force are perpendicular relative to Earth's surface at the magnetic south pole. -The lines of the magnetic force are parallel with Earth's surface at the equator. -The magnetic north pole may reverse so that it is located near the geographic south pole. -The lines of the magnetic force are perpendicular relative to Earth's surface at the magnetic north pole.
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. View Available Hint(s) -The ocean floor is spreading apart and new sea floor is forming. -Polar reversals cause existing ocean crust to remagnetize. -The igneous rock of the ocean floor preserves Earth's existing magnetic field as the rock cools. -The polarity of Earth's magnetic field experiences reversals. -Marine organisms that live on the sea floor have caused this pattern.
-The ocean floor is spreading apart and new sea floor is forming. -The igneous rock of the ocean floor preserves Earth's existing magnetic field as the rock cools. -The polarity of Earth's magnetic field experiences reversals.
What did the continents that formed during the break-up of the supercontinent 600 million years ago look like? -The shapes of the Atlantic Ocean continents were almost exactly like the shapes we see today. -They were nothing like the continent shapes we see on Earth today. -The shapes of the Pacific Ocean continents were almost exactly like the shapes we see today. -They were almost exactly like the continent shapes we see on Earth today.
-They were nothing like the continent shapes we see on Earth today.
Which of the following features are found at an oceanic-continental convergent plate boundary? Choose all that apply. View Available Hint(s) mountains island arc mid-ocean ridge trench continental arc
-mountains -trench -continental arc
Which of the following lines of evidence did Alfred Wegener use to support the concept of drifting continents? Choose all that apply. View Available Hint(s) -the distribution of species of fossils -evidence of glaciers in areas that are now tropical -the way the shapes of the continents fit together like pieces of a jigsaw puzzle -the composition of meteors from outer space -the pattern of similar mountain belts on different continents
-the distribution of species of fossils -evidence of glaciers in areas that are now tropical -the way the shapes of the continents fit together like pieces of a jigsaw puzzle -the pattern of similar mountain belts on different continents
Recent data indicate that at the time the offset of Wallace Creek began 13,000 years ago, it flowed through the valley indicated by placemark D, and only more recently did it cut its present channel into the land on the western side of the fault. Determine the average annual displacement, in inches, along this section of the San Andreas Fault. You can check your results with those published in the Field Trip Guide linked in placemark A. 1.2 inches/year 17,000 inches/year 0.1 inches/year 1,416 inches/year
1.2 inches/year
Look carefully at the course of Wallace Creek. Assuming that at one time it flowed straight across the San Andreas Fault, determine the relative motion of the fault. Then use the ruler tool to determine the current offset, in feet, of Wallace Creek where it crosses the San Andreas Fault. On which of the following diagrams is the relative motion of the fault and the displacement distance labeled correctly? Pay attention to the boxed arrows on the left side of the diagrams.
430 Right Left
When did the Appalachian Mountains of North America begin to form? 300 million years ago 150 million years ago 600 million years ago 250 million years ago 450 million years ago
450 million years ago
When did the great mountain ranges of southern Europe and Asia begin to form? 600 million years ago 300 million years ago 450 million years ago 50 million years ago
50 million years ago
Which of the following statements is most accurate? A moving Asia collided with a stationary India about 71 million years ago. A moving India collided with a stationary Asia about 30 million years ago. A moving India collided with a stationary Asia about 71 million years ago. A moving Asia collided with a stationary India about 30 million years ago.
A moving India collided with a stationary Asia about 30 million years ago.
Which of the following is an example of an oceanic-oceanic convergent plate boundary? San Andreas Fault Mendocino Fault East Pacific Rise Aleutian Islands Red Sea
Aleutian Islands
Which of the following is an example of an oceanic-continental convergent plate boundary? Aleutian Islands San Andreas Fault Himalaya Mountains Andes Mountains Mendocino Fault
Andes Mountains
Which of the following mountain ranges are examples of continental arcs? Andes and Cascades Andes and Hawaii East African Rift and Hawaii East African Rift and Cascades
Andes and Cascades
Which of the following mountain ranges are examples of continental arcs? East African Rift and Cascades Andes and Hawaii East African Rift and Hawaii Andes and Cascades
Andes and Cascades
What would happen to Earth if ocean floor were created at divergent boundaries at a faster rate than it is destroyed at convergent boundaries? Earth would decrease in volume. Earth would increase in volume. Earth would increase in mass. Earth would decrease in mass.
Earth would increase in volume.
How are Earth's geographic and magnetic axes oriented relative to each other? Earth's geographic and magnetic axes are oriented at a slight angle to each other. Earth's geographic and magnetic poles are oriented in opposite directions. Earth's geographic and magnetic poles are nearly perpendicular. Earth's geographic and magnetic axes are oriented identically.
Earth's geographic and magnetic axes are oriented at a slight angle to each other.
Which of the following is an example of an oceanic-oceanic divergent plate boundary? Red Sea Mendocino Fault San Andreas Fault Aleutian Islands East Pacific Rise
East Pacific Rise
Why are ocean basins continually being destroyed and created, rather than simply being redistributed around Earth's surface like continents? -Low-density continental crust subducts beneath high-density oceanic crust where plates converge. -High-density continental crust subducts beneath low-density oceanic crust where plates converge. -Low-density oceanic crust subducts beneath high-density continental crust where plates converge. -Low-density continental crust is created where plates rift and diverge. -High-density oceanic crust subducts beneath low-density continental crust where plates converge.
High-density oceanic crust subducts beneath low-density continental crust where plates converge.
Which of the following is an example of a continental-continental convergent plate boundary? Andes Mountains Aleutian Islands Himalaya Mountains Mendocino Fault San Andreas Fault
Himalaya Mountains
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? View Available Hint(s) Kauai Loihi Maui Hawaii Oahu
Kauai
Which of the following is an example of an oceanic transform plate boundary? Aleutian Islands Red Sea San Andreas Fault Mendocino Fault East Pacific Rise
Mendocino Fault
What piece of evidence supports Wegener's hypothesis of continental drift? View Available Hint(s) -Records of glacial masses in the tropics indicate a worldwide ice age. -Calculations of tidal forces show that this mechanism is sufficient to cause landmasses to move. -Rocks of varying ages found in mountain chains separated by the Atlantic Ocean indicate that they formed at different times in history.. -Coal deposits that form in tropical swamps are absent from continents near the poles.. -Modern-day species that evolved in isolation share a common ancestor.
Modern-day species that evolved in isolation share a common ancestor.
Which of the following statements is most accurate? Prior to 30 million years ago, Tibet was a much thinner landmass than it is today. Prior to 30 million years ago, Tibet was a much thicker landmass than it is today. Prior to 30 million years ago, Tibet was a much less dense landmass than it is today. Prior to 30 million years ago, Tibet was a much denser landmass than it is today.
Prior to 30 million years ago, Tibet was a much thinner landmass than it is today.
Which of the following is an example of a continental transform plate boundary? Aleutian Islands Himalaya Mountains San Andreas Fault Andes Mountains Mendocino Fault
San Andreas Fault
Which of the following statements is true regarding tectonic plates? View Available Hint(s) All tectonic plates are about the same size and shape. All plate boundaries trace the edges of the continents. Tectonic plate are composed of the crust and aesthenosphere. Tectonic plates may include both oceanic and continental crust. All of these statements are correct.
Tectonic plates may include both oceanic and continental crust.
What prompted the first widespread mapping of the ocean floor? View Available Hint(s) The laying of undersea telegraph lines between the United States and Europe The importance of submarine warfare during World War II Conflicts over maritime (ocean) territorial claims during the 1970s The sinking of the Titanic The creation of NASA
The importance of submarine warfare during World War II
Which of the following statements is true of the lithosphere? The lithosphere is composed of outer mantle material. The lithosphere is composed of the inner portion of the mantle and the outer core. The lithosphere is composed of metamorphic rock. The lithosphere is composed of the crust and the uppermost portion of the mantle. The lithosphere is composed of igneous rock.
The lithosphere is composed of the crust and the uppermost portion of the mantle.
What happens when an oceanic plate converges with a continental plate? View Available Hint(s) The two plates are forced upward, and a large mountain range is formed. A divergent plate boundary is formed. The two plates slide past each other. The continental plate is subducted. The oceanic plate is subducted.
The oceanic plate is subducted
As Heezen and Tharp interpreted the ocean depth data, they identified what unusual feature that hinted at continental drift? View Available Hint(s) Ocean ridges abruptly stop after a few hundred kilometers and then start again after a few hundred more. They discovered a chain of very tall volcanoes in the middle of the Atlantic Ocean that do not rise higher than the sea surface. The oceanic ridges have a cleft, or rift, in the middle rather than a peak. The oceanic ridges have a broad, flat top very much resembling a table top. Ocean ridges are unique to the Pacific Ocean.
The oceanic ridges have a cleft, or rift, in the middle rather than a peak
As Heezen and Tharp interpreted the ocean depth data, they identified what unusual feature that hinted at continental drift? View Available Hint(s) -Ocean ridges abruptly stop after a few hundred kilometers and then start again after a few hundred more. -They discovered a chain of very tall volcanoes in the middle of the Atlantic Ocean that do not rise higher than the sea surface. -The oceanic ridges have a cleft, or rift, in the middle rather than a peak. -The oceanic ridges have a broad, flat top very much resembling a table top. -Ocean ridges are unique to the Pacific Ocean.
The oceanic ridges have a cleft, or rift, in the middle rather than a peak.
As Heezen and Tharp interpreted the ocean depth data, they identified what unusual feature that hinted at continental drift? View Available Hint(s) Ocean ridges abruptly stop after a few hundred kilometers and then start again after a few hundred more. They discovered a chain of very tall volcanoes in the middle of the Atlantic Ocean that do not rise higher than the sea surface. The oceanic ridges have a cleft, or rift, in the middle rather than a peak. The oceanic ridges have a broad, flat top very much resembling a table top. Ocean ridges are unique to the Pacific Ocean.
The oceanic ridges have a cleft, or rift, in the middle rather than a peak.
Of the following statements about the age of the ocean crust, which one is true? Select only one answer. View Available Hint(s) The oldest ocean crust is about 200 million years old and is located near an ocean trench. The oldest ocean crust is about 200 million years old and is located near the mid-ocean ridge. The oldest ocean crust is about 2 million years old and is located near an ocean trench. The oldest ocean crust is about 2 million years old and is located near the mid-ocean ridge. The oldest ocean crust is about 4.5 billion years old and is located near the edge of a continent.
The oldest ocean crust is about 200 million years old and is located near an ocean trench.
Where is the youngest ocean floor found? along the edges of continents along chains of hot-spot volcanoes along the crest of mid-ocean ridges along the axis of ocean trenches
along the crest of mid-ocean ridges
What happens when a continental plate meets another continental plate? View Available Hint(s) -The denser continental plate will subduct. -A divergent plate boundary is formed. -Both plates are subducted. -The two plates slide past each other. -The two plates are forced upward, and a large mountain range is formed.
The two plates are forced upward, and a large mountain range is formed.
What did the maps of the ocean floor produced by Bruce Heezen and Marie Tharp reveal about seafloor topography? View Available Hint(s) There are ridges near the edges of the oceans, a few hundred miles from the edges of each of the continents. Ocean floors and continental areas are morphologically very similar to each other. There are ridges in the middle of the ocean basin floors. Ocean basins are very flat features. The seafloor data revealed that the middle of oceans is where continents appear to be drifting toward each other.
There are ridges in the middle of the ocean basin floors.
Why did Heezen and Tharp have to do "inspired guessing" when creating their maps of the ocean floor? View Available Hint(s) -They were given only a small portion of the depth data by the Navy. The rest was classified. -There were gaps in the data that were used to make the map because the tracks of the ships collecting the data were widely spaced. -Data could not be collected for parts of the ocean that were greater than 10,000 feet deep. -The data they used came from tracks of ships that overlapped each other. -They were limited by the mapping technology of the time.
There were gaps in the data that were used to make the map because the tracks of the ships collecting the data were widely spaced.
What do all plate boundaries have in common? Select only one answer. View Available Hint(s) They are all associated with zones of earthquakes. They are all located along the edges of continents. They occur only on the ocean floor. They are all associated with an abundance of volcanic activity. They occur entirely within the middle of continents.
They are all associated with zones of earthquakes
Imagine two people standing at placemark A and placemark E, looking at each other across the fault. Which of the following statements correctly describes the relative motion of the land opposite each observer? -To the observer at placemark A, the land at placemark E is moving to the right, and to the observer at placemark E, the land at placemark A is moving to the left. -To both observers, the land opposite them is moving to the left. -To the observer at placemark A, the land at placemark E is moving to the left, and to the observer at placemark E, the land at placemark A is moving to the right. -To both observers, the land opposite them is moving to the right.
To both observers, the land opposite them is moving to the right.
Did any subduction occur during the collision of India and Asia? Yes; ocean basin between these two continents subducted under Asia. Yes; ocean basin between these two continents subducted under India. Yes; a continent between these two continents subducted under India. Yes; another continent between these two continents subducted under Asia.
Yes; ocean basin between these two continents subducted under Asia.
Which type of plate boundary exists between India and Asia today? a subduction zone a divergent zone a transform boundary a convergent boundary
a convergent boundary
What is a volcanic arc? -a row of volcanoes that forms on the ocean floor above a hot spot -a row of volcanoes that forms on the ocean floor above a mid-ocean ridge -a row of volcanoes that forms on the overriding plate near a subduction zone -a row of volcanoes that forms on the subducting plate near a subduction zone
a row of volcanoes that forms on the overriding plate near a subduction zone
What is a volcanic arc? a row of volcanoes that forms on the overriding plate near a subduction zone a row of volcanoes that forms on the ocean floor above a mid-ocean ridge a row of volcanoes that forms on the ocean floor above a hot spot a row of volcanoes that forms on the downgoing plate near a subduction zone
a row of volcanoes that forms on the overriding plate near a subduction zone
On average, how long do periods of reverse and normal polarity last? about 50,000 years about 100,000 years about 500,000 years about 1 million years
about 500,000 years
Where is the youngest ocean floor found? along the axis of ocean trenches along the edges of continents along chains of hot spot volcanoes along the crest of mid-ocean ridges
along the crest of mid-ocean ridges
Which type of plate boundary is most closely associated with uplifting continental regions and mountain building? hot spot boundaries convergent boundaries divergent boundaries transform boundaries
convergent boundaries
The Mid-Atlantic Ridge is an example of a: convergent plate boundary (oceanic-oceanic). convergent plate boundary (continent-oceanic). divergent plate boundary. transform fault boundary. convergent plate boundary (continent-continent).
divergent plate boundary
What are the three types of plate boundaries? divergent, convergent, and transform divergent, converse, and transform digressive, convergent, and transform divergent, convergent, and transverse divergent, converse, and transverse
divergent, convergent, and transform
Plates move apart at __________ boundaries, move together at __________ boundaries, and move side by side at __________ boundaries. convergent/transform/divergent transform/divergent/convergent convergent/divergent/transform transform/convergent/divergent divergent/convergent/transform
divergent/convergent/transform
Plates move apart at __________ boundaries, move together at __________ boundaries, and move side-by-side at __________ boundaries. divergent/convergent/transform transform/divergent/convergent convergent/divergent/transform transform/convergent/divergent convergent/transform/divergent
divergent/convergent/transform
Seafloor depth was first determined by what remote sensing technology? View Available Hint(s) Satellites Radar Aerial photography Lidar Echo sounder
echo sounder
In general, what are the Himalayan mountains composed of? faulted and broken rock folded and bent rock folded and faulted rock extrusive volcanic rock
folded and faulted rock
Which phenomenon can explain the presence of volcanoes in the middle of the Pacific Ocean? earthquakes subduction hot spots divergence transform motion
hot spots
In general, how do magnetic objects align relative to Earth's magnetic field? parallel antiparallel perpendicular at an angle
parallel
Coral reefs ________. -can be found at latitudes above 60° -were first described by Christopher Columbus during his voyage to Hispaniola -form when underwater volcanoes are thrust upward during a tectonic event -are most common in deep and cold sub-tropical basins -include atolls, barrier, and fringing reefs
include atolls, barrier, and fringing reefs
Tectonic plates are pieces of the ________ that float on the more fluid ________ below. lithosphere; mesosphere lithosphere; asthenosphere mantle; crust crust; lithosphere asthenosphere; lithosphere
lithosphere; asthenosphere
Which geologic features are associated with divergent boundaries? mid-ocean ridges and continental rift valleys mid-ocean ridges and ocean trenches mid-ocean hot spots and continental rift valleys mid-ocean hot spots and ocean trenches
mid-ocean ridges and continental rift valleys
The Hawaiian Islands are located where the Pacific plate is: diving under Japan. being thrust over the North American plate. being subducted beneath Japan. moving over a hot spot or mantle plume. being subducted beneath the North American plate.
moving over a hot spot or mantle plume
Complete this statement: Divergence is to moving away as convergence is to _______. moving over moving toward moving side by side moving under
moving toward
Which geologic features are associated with convergent boundaries? mid-ocean ridges and continental rift valleys ocean trenches and volcanoes mid-ocean ridges and volcanoes ocean trenches and continental rift valleys
ocean trenches and volcanoes
Which geologic features are associated with convergent boundaries? ocean trenches and volcanoes mid-ocean ridges and continental rift valleys mid-ocean ridges and volcanoes ocean trenches and continental rift valleys
ocean trenches and volcanoes
What did the surface of Earth look like 600 million years ago? many small islands surrounded by ocean one large continent surrounded by ocean many small islands surrounded by magma one large continent surrounded by magma
one large continent surrounded by ocean
The seafloor magnetic pattern is best described as: perpendicular to and symmetric about mid-ocean ridges. parallel to and symmetric about mid-ocean ridges. parallel to, but not symmetric about mid-ocean ridges. not related to the location of mid-ocean ridges. perpendicular to, but not symmetric about mid-ocean ridges.
parallel to and symmetric about mid-ocean ridges
Fossils of ancient tropical plants are currently found near the poles because the: -plants were distributed to current locations by ancient glacial ice sheets. -poles were at the equator at times in the geologic past. -plants probably were tolerant of both tropical and polar conditions. -entire earth had warm, humid conditions at the time the plants were living. -plants lived in the tropics, but landmasses have drifted to current locations.
plants lived in the tropics, but landmasses have drifted to current locations.
When was the Precambrian eon? prior to 300 million years ago prior to 400 million years ago prior to 100 million years ago prior to 600 million years ago
prior to 600 million years ago
Deep ocean trenches are associated with: the mid-ocean ridge. subduction zones. rift valleys. submarine canyons. transform faults.
subduction zones
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 __________. View Available Hint(s) -the African Plate is essentially stationary with respect to Earth's interior and the thick continental crust acts as a "heat blanket" -the thick continental crust acts as a "heat blanket" and a large portion of Africa is located near the equator -a large portion of Africa is located near the equator -mantle plumes do not occur at divergent plate boundaries, and Africa has no divergent plate boundaries -Africa is just very large
the African Plate is essentially stationary with respect to Earth's interior and the thick continental crust acts as a "heat blanket"
Which mountain belt lies to the north of India? the Rockies the Himalayas the Andes the Alps the Cascades
the Himalayas
What would happen to Earth if ocean floor were created at divergent boundaries at a faster rate than it is destroyed at convergent boundaries? The Earth would increase in volume. The Earth would decrease in mass. The Earth would increase in mass. The Earth would decrease in volume.
the earth would increase in volume
What is meant by the term plate boundary? View Available Hint(s) the edge of a plate, where two plates meet each other the top of a plate, where the crust interacts with the atmosphere the entire tectonic plate the bottom of the plate, where the plate meets the core the bottom of a plate, where the plate meets the asthenosphere
the edge of a plate, where two plates meet each other