Geology Quiz 2

False

Iceland is a good example of an island arc, formed from an oceanic-oceanic plate collision. True False

normal and reversed magnetized strips roughly parallel to the ridge

Linear, magnetic patterns associated with mid-ocean ridges are configured as ________. concentric circles about a rising plume of hot, mantle rocks and magma reversed magnetizations along the rift valleys and normal magnetizations along the ridge normal and reversed magnetized strips roughly parallel to the ridge normal and reversed magnetized strips roughly perpendicular to the ridge axis

True

Seafloor spreading rates can be estimated if the geologic ages of the magnetic field reversals are independently known. True False

the jigsaw-puzzle fit of the continents

Which of the following observations was included as evidence for Wegener's continental drift hypothesis? ocean ridges the jigsaw-puzzle fit of the continents trenches at subduction zone boundaries seafloor spreading

All of the responses are correct.

Which of the following processes can be observed at the margins of lithospheric plates? faulting earthquakes volcanoes mountain building All of the responses are correct.

Marianas Trench

_____ _______ is located near/along Japan, China, Malaysia, and Indonesia.

sedimentary rock

. Layered _____ _______exposed by erosion can be seen when looking at the Grand Canyon in the United States.

True

Wegener's continental drift hypothesis was weakened because a viable mechanism for moving the continents was lacking. True False

a convergent plate boundary

Currently the Juan de Fuca plate is interacting with the North American plate where inland volcanoes and deep focus earthquakes are occurring. What type of plate boundary is this? a convergent plate boundary a divergent plate boundary a transform boundary a mantle plume a continental rift zone

sinking of oceanic lithosphere into the mantle at a subduction zone

Deep ocean trenches are surficial evidence for ________. rising of hot asthenosphere from deep in the mantle sinking of oceanic lithosphere into the mantle at a subduction zone transform faulting between an oceanic plate and a continental plate rifting beneath a continental plate and the beginning of continental drift

the subduction of lithosphere into the asthenosphere

Deep-ocean trenches are formed by _______. seafloor spreading the subduction of lithosphere into the asthenosphere the collision of continents motion along transform faults

Pacific

Deep-oceanic trenches are most abundant around the rim of the ________ ocean basin. Indian Arctic Atlantic Pacific

True

During various times in the geologic past, the polarity of Earth's magnetic field has been reversed. True False

seafloor spreading

The slowly increasing distance between South America and Africa is due to______ _______

a deep, vertical fault along which two plates slide past one another in opposite directions

A transform plate boundary is characterized by ________. two, converging, oceanic plates meeting head-on and piling up into a mid-ocean ridge stratovolcanoes on the edge of a plate and shield volcanoes on the adjacent plate a deep, vertical fault along which two plates slide past one another in opposite directions a divergent boundary where the continental plate changes to an oceanic plate

hot spot

A very long-lived magma source located deep in the mantle is called a ________. hot spot melt well basalt spout magma welt

changes in the Moon's orbit due to shifting plates

All of the following are evidence supporting the theory of plate tectonics except for ________. ocean floor drilling hot spots measurements of plate motions changes in the Moon's orbit due to shifting plates

False

As the South Atlantic basin widens by seafloor spreading, Africa and South America are moving closer together. True False

continental crust.

Australia is composed of relatively old and thick ______ ______

asthenosphere

Beneath Earth's lithosphere, the hotter, weaker zone known as the _____ allows for motion of Earth's rigid outer shell. asthenosphere crust plate boundaries oceanic crust outer core

subduction zones along convergent plate boundaries

Cooler, older, oceanic lithosphere sink into the mantle at ________. rift zones along mid-ocean ridges sites of long-lived, hot spot volcanism in the ocean basins transform fault zones along divergent plate boundaries subduction zones along convergent plate boundaries

the outermost portion of the mantle

Earth's lithospheric plates are composed of crust and which of the following layers? the outermost portion of the core the innermost portion of the mantle the core the outermost portion of the mantle the middle portion of the mantle

False

Earth's radius and surface area are slowly increasing to accommodate the new oceanic crust being formed at mid-oceanic ridges. True False

convergent boundary on a volcanic arc above a northward-subducting Pacific plate

The Aleutian Islands occur at a ________. transform boundary where North America has moved towards Alaska convergent boundary on a volcanic arc above a northward-subducting Pacific plate convergent, continental margin with uplifted fault blocks, much like those of the Basin and Range Province divergent boundary where shield volcanoes are forming

young, active volcanoes built on a continental margin above a sinking slab of oceanic lithosphere

Mount St. Helens and the other Cascade volcanoes are ________. a row of young, active, volcanoes built as western North America moved over a hot spot deep in the mantle old, deeply eroded, basaltic volcanoes built when western North America was over the present-day site of the Hawaiian hot spot young, active volcanoes built on a continental margin above a sinking slab of oceanic lithosphere old, deeply eroded volcanoes built before the Pacific Ocean existed

divergent boundaries by submarine eruptions and intrusions of basaltic magma

New oceanic crust and lithosphere are formed at ________. convergent boundaries by submarine eruptions and intrusions of rhyolitic magma divergent boundaries by submarine eruptions and intrusions of basaltic magma divergent boundaries by submarine eruptions and intrusions of rhyolitic magma convergent boundaries by submarine eruptions and intrusions of basaltic magma

a mantle plume

The Hawaiian Islands were formed as a result of ___________. seafloor spreading ocean-ocean convergent boundary ocean-continent convergent boundary a mantle plume

True

The Himalayan Mountains are the tectonic product of a collision between India and Eurasia that began about 40 million years ago and still continues. True False

Red Sea

The ________ is (are) a logical evolutionary analog of the African Rift Valleys ten million years from now. Ural Mountains Red Sea San Andreas fault Peru-Chile trench

True

The oldest rocks of the oceanic crust are found in deep ocean trenches far away from active, mid-ocean ridges. True False

True

The oldest rocks on the seafloor are much younger than the oldest rocks on the continents. True False

False

The rate of seafloor spreading is, on the average, about one meter per year. True False

continental rift along which parts of the African continent are beginning to slowly separate

The volcanoes and deep valleys of east Africa are related to a ________. continental rift along which parts of the African continent are beginning to slowly separate continental collision zone between Africa and the Zagros Mountains along the southern margin of Eurasia transform fault aligned with the Red Sea carrying the Arabian and African blocks in opposite directions fault allowing Arabia to slip westward past east Africa and penetrate into Turkey

True

The volcanoes of Hawaii are localized above a deep mantle hot spot; they are not part of the East Pacific oceanic ridge. True False

Seafloor crust

______ _______ found in the Atlantic Ocean between North America and Europe is composed of dense and relatively young rock.

a divergent plate boundary

Pull-apart, rift zones are generally associated with ________. a transform plate boundary a convergent plate boundary a divergent plate boundary all plate boundaries

2 centimeters per year

A typical rate of seafloor spreading in the Atlantic Ocean is ________. 0.1 inches per year 2 centimeters per year 20 feet per year 2 feet per year

hot spot

Old Faithful Geyser at Yellowstone National Park in the United States acquires its energy from a ______ ______

True

In general, rocks of the continental crust are less dense than rocks of the oceanic crust. True False

Due to tectonic activity, rocks on the ocean floor are continually recycled.

In studies of rock obtained from ocean basins all over Earth, the oldest ages obtained are approximately 200 million years before the present. Why have no older oceanic rocks been discovered? 1. As the lithospheric plates move around, most of the ocean floor rocks are pushed up to form mountains. 2. Due to tectonic activity, rocks on the ocean floor are continually recycled. 3. Ocean floor is dispersed by volcanic eruptions. 4. Scientists haven't sampled enough sites to find older rocks. 5. The age of Earth is 200 million years.

Alfred Wegener

In the early part of the 20th century, ________ argued forcefully for continental drift. Peter Rommel Alfred Wegener Bill Kohl Karl Wagner SubmitMy AnswersGive Up

northward movement of India into Eurasia westward movement of the South American

The ________ is an example of an active, continent-continent collision. northward movement of India into Eurasia westward movement of the South American plate over the Nazca plate northern movement of Baja California and a sliver of western California toward the Hawaiian Islands Arabian Peninsula slamming into North Africa under the Red Sea

identify a mechanism capable of moving continents

The continental drift hypothesis was rejected primarily because Alfred Wegener could not ________. disprove competing theories that were more accepted by scientists find geologic similarities on different continents identify a mechanism capable of moving continents all of the above

fault.

The earthquakes that occur in Southern California generally occur along a ______

subduction

The extremely deep ocean Marianas Trench is a result of _______

Pangaea

The former, late Paleozoic super continent is known as ________. Pangaea Pandomonia Pancakea Panatopia

a rift zone that may eventually open into a major ocean if Arabia and Africa continue to separate

The modern-day Red Sea is explained by plate tectonics theory because it is ________. a tiny remnant of a once immense ocean that was closed as Africa moved Asia a rare example of a two-continent subduction zone where the African continental plate is sinking under the Arabian continental plate the site of a transform fault along which Arabia is moving away from Africa a rift zone that may eventually open into a major ocean if Arabia and Africa continue to separate

divergent boundary

Which boundary is characterized as a long, linear rise in the seafloor, with shallow earthquakes and volcanic activity found along its length? divergent boundary subduction zone transform boundary continent-continent convergent boundary

export of heat from deep in the mantle to the top of the asthenosphere

Which of the following energy sources is thought to drive the lateral motions of Earth's lithospheric plates? swirling movements of the molten iron particles in the outer core export of heat from deep in the mantle to the top of the asthenosphere gravitational attractive forces of the Sun and Moon electrical and magnetic fields localized in the inner core

The crust of the oceans is very young relative to the age of the continental crust.

Which of the following is one of the remarkable realizations associated with the discovery of seafloor spreading? The crust of the oceans is very young relative to the age of the continental crust. The crust of the continents is denser than the crust of the ocean. Mountains are denser than mantle. The Hawaiian Islands were formed by subduction.

the Philippine plate

Which of the following lithospheric plates is not included among the seven largest? the Philippine plate the African plate the Antarctic plate the South American plate the Australian-Indian plate

zone in the upper mantle that deforms by plastic flowage

Which of the following statements apply to the asthenosphere, but not the lithosphere? cool, rigid layer of crust and upper mantle that forms the tectonic plates zone in the upper mantle that deforms by plastic flowage partial melting of rising granitic plumes produces huge volumes of basaltic magma deforms mainly by brittle fracturing and faulting

Earth's diameter has been essentially constant over time.

Which one of the following is an important fundamental assumption underlying the plate tectonic theory? Earth's ocean basins are very old and stable features. Earth's magnetic field originates in the outer core. Radioactive decay slows down at the extreme pressures of the inner core. Earth's diameter has been essentially constant over time.

shield volcanoes fed by a long-lived hot spot below the Pacific lithospheric plate

Which one of the following most accurately describes the volcanoes of the Hawaiian Islands? stratovolcanoes associated with a mid-Pacific transform fault shield volcanoes fed by a long-lived hot spot below the Pacific lithospheric plate stratovolcanoes associated with subduction and a convergent plate boundary shield volcanoes associated with a mid-Pacific ridge and spreading center