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earth science m-term
chapters 1-8
Question | Answer |
---|---|
Intrusive rocks ________. | are generally fine-grained? are quite often vesicular? form at Earth's surface? none of these |
Metamorphism can affect only sedimentary rocks. | false |
Quartz is quite resistant to weathering and is an important component of sands in riverbeds and on beaches. | true |
________ is a strong, parallel alignment of different mineral bands in a metamorphic rock. | Foliation |
Rocks are aggregates of one or more minerals. | True |
Glassy igneous rocks form when magma cools so slowly that mineral crystals cannot grow. | False |
Olivine and quartz are commonly found together in the same rock. | False |
As the rate of cooling increases, the size of the crystals that form ________. | decreases |
One magma can produce several different igneous rocks having different mineral compositions. | True |
All atoms of the same element have the same atomic number. | True |
The most unreliable (variable) diagnostic property of minerals such as quartz is ________. | Color |
Which the following denotes the positively charged particles in an atom's nucleus? | Protons |
Atoms of the same element, zinc for example, have the same number of ________. | protons in the nucleus |
Select the coarse-grained rock which is composed mainly of quartz and potassium feldspar from the list below. | granite |
A mineral can be composed entirely of one element. | True |
Sedimentary rocks ________. | may contain fossils, hold important clues to Earth’s history, and may be economically important. all of these |
Which of these factors influence the type and rate of weathering? | mineral content, climate, and topography. all of these |
Detrital sediments would predominate in all of the following environments except ________. | salt flat |
Atoms that have an electrical charge due to a gain or loss of electrons are called ________. | ions |
The texture of an igneous rock ________. | records the rock's cooling history |
What element is the most abundant in the Earth's crust by weight? | oxygen |
Metamorphism may result from ________. | heat, pressure, chemical action, all of these |
The most abundant chemical sedimentary rock is ________. | limestone |
Electrically neutral atoms have equal numbers of electrons and protons. | True |
Detrital sedimentary rocks are classified (named) primarily on the basis of ________. | particle size |
Which one of the following is an igneous rock? | rhyolite |
In the silicon-oxygen tetrahedron there are more silicon atoms than oxygen atoms. | False |
Which of the following minerals is a silicate? | Feldspar |
Which of the following best defines a mineral and a rock? | in a mineral the constituent atoms are bonded in a regular, repetitive, internal structure; a rock is a lithified or consolidated aggregate of different mineral grains |
Which of the following best describes bedded gypsum and rock salt? | evaporites; chemical, sedimentary rocks |
The ion at the center of a silicon-oxygen tetrahedron is surrounded by ________. | 4 oxygen ions |
Which pair of minerals is most common in detrital sedimentary rocks? | clay and quartz |
Which one of the following is NOT true about mechanical weathering? | does not affect metamorphic rocks |
Evaporites have a biochemical origin. | False |
Which one of the following is not true for minerals? | they can be a liquid, solid, or glass |
An atom's mass number is 13 and its atomic number is 6. How many neutrons are in its nucleus? | 13-6=7 |
All silicate minerals contain which two elements? | silicon, oxygen |
The resistance of a mineral to abrasion is known as ________. | hardness |
Isotopes of the same element have the same mass number. | False |
Most minerals have a higher specific gravity than water. | True |
Which of the following is NOT one of the eight most common elements in Earth's crust? | Carbon |
Which group of minerals are the most abundant in the Earth's crust? | silicates |
This igneous texture is characterized by two distinctively different crystal sizes. | porphyritic |
The primary agent of contact metamorphism is ________. | heat |
All minerals exhibit cleavage. | False |
Most limestone has a biochemical origin. | True |
Metamorphism is commonly associated with mountain building. | True |
Which of the following is correct for isotopes of the same element? | the atoms have different numbers of neutrons and the same number of protons |
The strong tendency of certain minerals to break along smooth, parallel planes is known as ________. | cleavage |
The water table is ________. | a boundary between saturated rock below and unsaturated rock above |
The source of heat for most hot springs is hot igneous material beneath the surface. | True |
A ________ forms when a block of ice is buried in drift and subsequently melts creating a pit. | Kettle |
The transfer of rock material down slope under the influence of gravity is termed ________. | mass wasting |
________ is not part of the water cycle? | Calcium carbonate dissolving in soil water and groundwater |
Running water is not an important erosional agent in deserts because rainfall is infrequent. | False |
Abrasion and plucking generally involve what part of a glacier? | the basal, sliding zone |
Alluvium is the general term for any sediment deposited by a stream. | True |
A broad accumulation of stratified drift deposited adjacent to the downstream edge of an end moraine is a ________. | Outwash plain |
________ is an irregular, usually thin till layer laid down by a retreating glacier. | Ground moraine |
A ________ stream pattern is developed only on growing mountains like volcanoes or where the land surface is tectonically doming upward. | Radial |
At the head of a delta, the major channel splits into smaller channels that follow different paths to the sea. These smaller channels are known as ________. | distributaries |
The controlling force of mass wasting is ________. | gravity |
A cirque represents an erosional feature formed in what was an important accumulation zone for snow and ice at the upstream head of a glacier. | True |
Moraines are the only glacial deposits composed of till. | False |
Which one of the following concerning artesian wells is NOT true? | when the well penetrates the aquifer, the water rises in the well to the bottom of the overlying aquitard |
Which of the following features characterize wide streams and valleys? | natural levees; broad floodplains |
The single most important erosional agent is ________. | running water |
Fiords are found exclusively along the coast of Norway. | False |
The formation of stalactites and stalagmites occurs in the zone of saturation. | False |
________ generally constitutes the highest percentage of the annual sediment load moved by a stream. | Suspended load |
Where is the world's largest ice sheet located today? | Antartica |
One environmental problem associated with groundwater is land subsidence caused by withdrawal. | True |
If you were to examine the longitudinal profile of a typical river, you would probably find that the gradient is ________. | steepest near the head |
Loess consists mainly of silt-sized particles. | True |
________ is one of the two, major flow mechanisms in a glacier. | Basal slip |
Glacial melting and calving occur in the zone of wastage. | True |
Point bars are depositional features located along the outer banks of meander bends. | False |
Drumlins are ________. | not found singly, but in clusters |
________ are characteristics of downcutting streams and a youthful stage of valley evolution. | Rapids and lots of whitewater |
Gravity plays an important role in all mass wasting events. | True |
Desert pavement is the result of ________. | deflation |
As its name implies, the water table is always very level (flat). | False |
A(n) ________ is likely to host a waterfall or steep rapids today. | hanging valley |
Which one of the following is NOT true of glaciers? | exist only in the Northern Hemisphere |
Loose, undisturbed particles assume a stable slope called the angle of repose. | True |
Steppes are the driest of the true desert lands. | False |
When water is pumped from a well, a depression is often produced in the water table. Such a depression is a(n) ________. | cone of depression |
Which one of the following applies to a valley glacier that lengthens (extends its terminus downslope) over a period of many years? | accumulation exceeds wastage |
At a bend in a river, the main erosion is ________. | on the outside of the bend |
Desert and steppe lands cover about what percentage of Earth's land area? | 30% |
Rapid surge movements of the Earth's tectonic plates offer a convincing explanation for the advances and retreats of the Pleistocene ice sheets. | False |
A(n) ________ represents a former meltwater channel or tunnel in glacial ice that was filled with sand and gravel. | esker |
A ________ cross-valley profile is typical of canyons and valleys eroded and deepened by alpine or valley glaciers. | U-shaped |
The term "drift" ________. | means any sediments of glacial origin |
A fiord is a ________. | drowned glacial trough |
More water is evaporated from the ocean than is returned by precipitation over the ocean. | True |
Blowouts are broad, shallow depressions excavated by deflation. | True |
Which of the following best describes how geysers erupt? | with a slight reduction in pressure, water in a saturated, natural conduit suddenly boils, sending a plume of steam and hot water into the air above the vent |
Which of the following terms is used to describe the way materials move during a mass wasting event? | Fall, slide, flow, all of these. |
An extensive, late Paleozoic glaciation affected southern India, southern Africa and southeastern South America. | True |
A transform plate boundary is characterized by ________. | a deep, vertical fault along which two plates slide past one another in opposite directions |
Cooler, older, oceanic lithosphere sink into the mantle at ________. | subduction zones along convergent plate boundaries |
Seafloor spreading rates can be estimated if the geologic ages of the magnetic field reversals are independently known. | True |
________ most effectively outline the edges of the lithospheric plates. | Lines of earthquake epicenters |
Hawaii is the oldest island of the Hawaiian Island chain. | False |
The oldest rocks of the oceanic crust are found in deep ocean trenches far away from active, mid-ocean ridges. | True |
The modern-day Red Sea is explained by plate tectonics theory because it is ________. | a rift zone that may eventually open into a major ocean if Arabia and Africa continue to separate |
Which of the following paleoclimatic evidence supports the idea of the late Paleozoic super continent in the Southern Hemisphere? | tillites (rocks formed by glaciers) in South Africa and South America |
Which of the following energy sources is thought to drive the lateral motions of Earth's lithospheric plates? | export of heat from deep in the mantle to the top of the asthenosphere |
Earth's radius and surface area are slowly increasing to accommodate the new oceanic crust being formed at mid-ocean ridges. | False |
Pull-apart, rift zones are generally associated with a ________ plate boundary. | divergent |
The volcanoes of Hawaii are localized above a deep mantle hot spot; they are not part of the East Pacific oceanic ridge. | True |
________ was never proposed as evidence supporting the existence of Pangaea. | Islands of Precambrian rocks along the Mid-Atlantic Ridge |
In the early part of the 20th century, ________ argued forcefully for continental drift. | Alfred Wegener |
The rate of seafloor spreading is, on the average, about one meter per year. | False |
Where would you drill to recover samples of the oldest basalts of the oceanic crust, which are Jurassic in age? | oceanic side of the Aleutian trench |
Which of the following statements apply to the asthenosphere, but not the lithosphere? | zone in the upper mantle that deforms by plastic flowage |
The ________ is an example of an active, continent-continent collision? | northward movement of India into Eurasia |
The temperature below which magnetic material can retain a permanent magnetization is called the ________. | Curie point |
A very long-lived magma source located deep in the mantle is called a ________. | hot spot |
In general, rocks of the oceanic crust are less dense than rocks of the continental crust. | False |
________ was an ancient reptile that lived in South America and Africa during the late Paleozoic. | Mesosaurus |
During various times in the geologic past, the polarity of Earth's magnetic field has been reversed. | True |
The continental drift hypothesis was rejected primarily because Alfred Wegener could not ________. | identify a mechanism capable of moving continents |
In a ________ fault, the hanging wall block moves up with respect to the footwall block. | reverse |
S waves can travel through solid and liquid media. | False |
The Black Hills of South Dakota are a good example of a(n) ________. | dome |
Which of the following combinations should favor folding rather than faulting? | high temperature and high confining pressure |
Approximately how much more energy is released in a 6.5 Richter magnitude earthquake than in one with magnitude 5.5? | 30 times |
The asthenosphere is located ________. | in the upper mantle |
Which one of the following statements about the crust is NOT true? | oceanic crust is enriched in potassium, sodium, and silicon |
Oceanic crust is generally thicker than continental crust. | False |
The ________ earthquake was accompanied by extensive fire damage. | San Francisco, 1906 |
The lithosphere is defined as ________. | a rigid layer of crustal and mantle material |
Basin and range topography, like that in the western and southwestern United States, indicates that compressive folding is active today or was active very recently, geologically speaking. | False |
The ________ in California is the boundary between the North American and Pacific plates. | San Andreas strike-slip fault |
Brittle deformation would be favored over plastic deformation in which of the following conditions? | cooler temperatures |
The Mercalli Scale is a scale from ________. | I to XII that rates the structural damage due to an earthquake |
The record of an earthquake obtained from a seismic instrument is a(n) ________. | seismogram |
On a seismogram, ________ will show the highest amplitudes. | surface waves |
Earthquakes result from the sudden release of elastic strain energy previously stored in rocks surrounding a zone of fault movement. | True |
Large circular downwarped structures are called ________. | Basins |
Accretionary wedges develop along subduction zones where sediments and other rocks are scraped off a descending plate and piled against the leading edge of the overriding plate. | True |
In a reverse fault, the hanging wall block moves up relative to the footwall block. | True |
The Richter magnitude of an earthquake is based on the ________. | amplitude of the largest seismic wave recorded |
A horst is ________. | an uplifted block bounded by two normal faults |
The mechanism by which rocks store and eventually release energy in the form of an earthquake is termed ________. | elastic rebound |
Most of our knowledge about Earth's interior comes from ________. | seismic waves |
The ________ is (are) characterized by terrane accretion that has been active throughout most of Mesozoic and Cenozoic time. | western margin of North America |
A ________ volcano is a very large, gently sloping mound composed mainly of basaltic lava flows. | shield |
A ________ is a near surface, intrusive, igneous rock body that results from local inflation of a horizontal sill. | laccolith |
________ destroyed the city of St. Pierre, Martinique in 1902. | A nueé ardente |
________is a major dissolved constituent in both magmas and volcanic gasses. | Water vapor |
The active Hawaiian volcanoes are situated directly above a major boundary between two of the Earth's largest tectonic plates. | False |
Volcanism along divergent plate boundaries where seafloor spreading is occurring produces rocks which are ________. | basaltic in composition |
Repeated eruptions of relatively fluid lava from fissures can eventually cause an area to be covered by flood basalts. | True |
The recent (geologically) volcanic activity in Yellowstone National Park is ________. | related to intraplate, hot spot volcanism |
Which of the following is associated with deep mantle hot spots? | the volcanoes of Hawaii and Quaternary activity in Yellowstone National Park |
Kilauea and Mauna Loa are ________. | basaltic shield volcanoes |
What volcanic events formed Crater Lake, OR? When did they take place? | caldera collapse followed major ash and pyroclastic-flow eruptions; 7000 years ago |
The largest igneous intrusive body is called a(n) ________. | batholith |
Vents that emit only heated, volcanic gases are called fumaroles. | True |
The most violent volcanic activity is associated with ________. | composite cones |
Paricutin is an example of a ________. | cinder cone |
In general, cinder cones are much larger than shield volcanoes. | False |
Most of the stratovolcanoes on Earth are located in a belt known as the ________. | Ring of Fire |
Which type of basaltic lava flow has a fairly smooth, unfragmented, ropy surface? | pahoehoe |
________ tend to increase the explosive potential of a magma body beneath a volcano. | High viscosity and dissolved gas |
Which of the following statements best describes the big Hawaiian volcanoes? | are situated in the interior of a large, Pacific plate above a hot spot deep in the mantle |
Small amounts of water can lower partial melting temperatures in silicate rocks. | True |
Which type of basaltic lava flow has its surface covered with sharp-edged, angular blocks and rubble? | aa |
Kilauea is an example of a ________. | Shield volcano |
Magma generation at depth almost always involves partial melting, not complete melting of the source rock. | True |
________ is an erosional contact between tilted, older strata below and horizontal, younger strata above. | An angular unconformity |
The half-life of carbon-14 is about 6000 years. Assume that a sample of charcoal formed by burning of living wood 15,000 years ago. How much of the original carbon-14 would remain today? | between one-fourth and one-eighth |
After three half-lives, one-ninth of an original, radioactive, parent isotope remains and eight-ninths has decayed into the daughter isotope. | False |
What fundamental concept states that in a horizontal sequence of conformable sedimentary strata, each higher bed is younger than the bed below it? | law of superposition |
What of the following refers to the investigative process by which geologists identify and match sedimentary strata and other rocks of the same ages in different areas? | correlation |
Correlation of rock units between continents or widely separated areas is accomplished by using physical features such as color, texture, and thickness of units. | False |
Sandstone strata and a mass of granite are observed to be in contact. Which of the following statements is correct geologically? | the granite is older if the sandstone contains pebbles of the granite |
By applying the law of superposition ________ dates can be determined. | relative |
Assume that you have just examined several flat-lying sedimentary layers. After much study you determine that there is a considerable span of time for which no sedimentary rock layer exists at this site. You have just discovered a(n) ________. | disconformity |
About 88 percent of geologic time is represented by the time span called the ________. | Precambrian |
A worm would stand a poor chance of being fossilized because ________. | worms have no hard parts |
An unconformity is a buried ________. | surface of erosion separating younger strata above from older strata below |
The percentage of radioactive isotope remaining in a rock sample is 40%. How many half-lives have elapsed since the material was 100% parent atoms? | between l and 2 |
Visualize five, horizontal, sedimentary strata exposed in a cliff or canyon wall identified by consecutive numbers, 1 being the lowest bed and 5 being the highest. Which of the following statements concerning the strata are true? | beds l and 3 are older than bed 4 |
The ________ is the idea or concept that ancient life forms succeeded each other in a definite, evolutionary pattern and that the contained assemblage of fossils can determine geologic ages of strata? | principle of fossil succession |
When a beta particle is emitted, the mass number of the isotope remains unchanged. | True |
Radiometric dating means placing events in their proper sequence. | False |
Which of the following is not a very long-lived, radioactive isotope? | C-14 |
What is the age of the Earth accepted by most scientists today? | 4.5 billion years |
Which of the following geologic observations would not bear directly on working out the sequence of geologic events in an area? | the feldspar and quartz contents of a granite |
Which of the following is an essential characteristic of an index fossil? | the organism only lived for a short period of geologic time |
The geologic time scale was devised before numerical dating using radioactivity was invented. | True |
When a radioactive isotope decays by electron capture, the electron ________. | combines with a proton in the nucleus; the atomic number of the daughter is one less than the parent |
Who is credited with formulating the doctrine of uniformitarianism? | Hutton |
Which of the following describes radioactive decay by beta particle emission? | the atomic number of the daughter isotope is one more than the parent; the mass numbers are the same |