Geology
____ waves are the fastest body waves generated by an earthquake
P
Precambrian refers to all the time before the start of the ____ Eon
Phanerozoic
Geologists learned that the outer core is liquid because ____ do not travel through the outer core
S waves
Which of the following describes a crystal?
a substance whose atoms are arranged in a regular, orderly, periodically repeated pattern
Beyond the Mid-Oceanic Ridge system are flat, level, featureless submarine surfaces called ____________________ ____________________
abyssal plans
If a series of island arcs collide with a continent over a long period of time, they add to a continent as:
accreted terranes
When two oceanic plates converge, the sinking plate drags the sea floor down to create:
an oceanic trench
An unconformity in which tectonic activity tilted older sedimentary rock layers before younger sediment accumulated is:
angular unconformity
A nonmetallic resource is:
any useful rock or mineral that is not a metal, such as salt, building stone, sand, or gravel
P, or primary, waves:
are characterized by alternate compression and expansion of rock
The ____________________ is the hot, weak, and plastic uppermost portion of the mantle
asthenosphere
The ____________________ is a mixture of gases, mostly nitrogen and oxygen.
atmosphere
A circular coral reef that forms a ring of island around a central lagoon is a/an ____________________
atoll
Most of the world's iron is mined from:
banded iron formations
Most of the oceanic crust is made up of ____________________, whereas most of the continental crust is composed of ____________________
basalt and granite
Oceanic crust is typically of ____ composition
basaltic
A pluton with an outcrop area of more than 100 square kilometers is a:
batholith
____ is formed as a residual deposit in warm climates.
bauxite
Tar sands are permeated with ____
bitumen
The color of ____ is caused by precipitation of fine-grained metal sulfide minerals
black smokers
Bioclastic sediment consists of:
broken shell fragments and similar remains of living organisms
A/An ____ is a crater formed by the collapse of a magma chamber
caldera
Mineral reserves:
can increase because new and inexpensive methods of processing lower grade ore can be developed and can become profitable if the price of the metal in a mineral deposit increases
____________________ is a principle that states that occasional huge catastrophes alter the course of Earth history.
catastrophism
Coal reserves are thought to be sufficient to last a few ____
centuries
Which physical properties distinguish a particular mineral from all others?
chemical composition and crystalline structure
Minerals are classified according to their:
chemical elements
At sea-floor vents, bacteria produce energy from hydrogen sulfide in a process called:
chemosynthesis
Sandstone, siltstone, and shale are ____ rocks.
clastic sedimentary
The tendency of some minerals to break along flat surfaces is called ____________________.
cleavage
As peat is buried and compacted by overlying sediment, it converts to ____________________.
coal
Layers of sedimentary rock are ____ if they were deposited without detectable interruption
conformable
Alfred Wegener proposed in his ____________________ ____________________ theory that Earth's continents were once joined together and later split and moved apart
continental drift
The Himalayan Mountain Range is an example of a ____ boundary
convergent
A tectonic plate is composed of:
cool, rigid rock that rides on a plastic mantle layer.
The geosphere consists of three major layers: the ____________________, ____________________, and ____________________.
core, crust, mantel
Matching rocks of similar ages from different localities is ____________________
correlation
Oceanic crust is ____ than continental crust and therefore ____ isostatically
denser; sinks
On the Mohs hardness scale, the hardest mineral is:
diamond
A/An ____________________ is an unconformity in which the sedimentary layers above and below the unconformity are parallel
disconformity
The San Andreas Fault zone is an example of a/an:
earthquake zone at a transform plate boundary
When solid rock deforms and returns to its original shape, it has undergone:
elastic deformation
The ____ is located on Earth's surface directly above the initial rupture point of an earthquake
epicenter
Pyroclastic bombs, cinders, and ash:
erupt explosively from volcanoes
The consequence of the vastness of geologic time is that:
events that occur slowly become significant
A feedback mechanism occurs when the environment initially changes slowly or not at all in response to a small perturbation, but after the threshold is crossed, an additional small perturbation causes rapid and dramatic change.
false
Fossil fuels are renewable
false
Oceanic crust is thicker than continental crust
false
Rocks and minerals in their natural state are never harmful to humans and other organisms.
false
The principle of ____________________ ____________________ states that species succeeded one another through time in a definite and recognizable order
faunal succession
A/An ____________________ ____________________ occurs when a small initial perturbation affects another component of the system, which amplifies the original effect.
feedback mechanism
Gentle eruptions of basaltic lava from long fissures create ___
flood basalts
A shield volcano commonly erupts when:
fluid basaltic magma builds a gently sloping mountain
The initial rupture point of an earthquake (below Earth's surface) is the ____
focus
Parallel growth of mica (and other minerals) during metamorphism and deformation of shales produces layering called ____________________
foliation
Fossil fuels are:
formed from the remains of plants and animals
A composite cone:
forms by repeated lava flows and pyroclastic eruptions over a long time
Petroleum, coal, and natural gas are called ____________________ ____________________ because they formed from the remains of plants and animals that lived in the geologic past.
fossil fuels
An example of a metamorphic change in which the new rock has a new texture, but the same minerals, is the transformation of ____ to ____.
limestone, marble
During the process of ____, soil loses its shear strength and becomes a fluid
liquefaction
The ____ includes Earth's crust and the uppermost strong and rigid part of the mantle
lithosphere
The rigid, outer part of Earth, including the crust and the uppermost mantle, is called the ____.
lithosphere
According to the theory of isostasy, the ____ is in floating equilibrium on the ___
lithosphere, asthenosphere
Granitic magma has a/an ____ melting temperature compared to basaltic magma
lower
The Mid-Oceanic Ridge is elevated above the surrounding sea floor because it is:
made of the newest, hottest, and lowest-density lithosphere
Extrusive igneous rocks form when:
magma erupts and solidifies on the Earth's surface
____ have occurred on average every 500,000 years over the past 65 million years of Earth's history
magnetic reversals
Remote sensing devices used to study the ocean floor are:
magnetometers; echo sounders; microwave radar instruments
The process by which rocks and minerals change in response to changing temperature, pressure, and/or chemical composition within the crust is ____________________
metamorphism
____________________ ____________________ is a mixture of clay carried from continents and the remains of tiny plants and animals that live in the surface waters of the oceans
pelagic sediment
Granite is an example of a/an ____ rock.
plutonic
Igneous rocks that solidify within the Earth's crust are ____________________.
plutonic; intrusive
The ____________________ encompasses approximately the first 4 billion years of Earth's history
precambrian
Evaporite deposits form by ____
precipitation from water
Melting caused by decreased pressure is called ____ melting
pressure-release
explosively erupted rock particles or magma form ____________________ rock
pyroclastic
Measurement of ____ age refers only to the order in which events occurred
relative
____________________ energy resources are replenished by natural processes as we use them
renewable
The same mineral that solidifies slowly to form granite can also erupt to form ____.
rhyolite
A mantle plume is a ____
rising column of hot, plastic mantle rock
At a divergent boundary between spreading tectonic plates in oceanic crust:
rock and magma rise to form the Mid-Oceanic Ridge
Weathering and erosion near the Earth's surface create the materials for ____ rocks.
sedimentary
About 5 percent of the Earth's crust is made of
sedimentary rocks
___ waves are elastic waves traveling through rock, produced by an earthquake
seismic
Feldspar is a/an ____ mineral.
silicate
Ninety-two percent of the Earth's crust is composed of ____________________ minerals.
silicate
Quartz is composed of ____.
silicon and oxygen
Igneous rocks form by
solidification of magma
Magma with a high water content has a greater tendency to ____ in the crust, compared with magma with a lower water content
solidify
Where two tectonic plates move past one another, rock near the plate boundary can stretch or compress elastically for decades, and then fracture suddenly and create an earthquake
true
A/An ____________________ is a sea wave generated by an underwater earthquake
tsunami
Submarine canyons on continental shelves and slopes are cut by ___
turbidity currents
At a transform boundary:
two plates slide horizontally past each other
____ means that the geologic processes operating today also worked in the past.
uniformitarianism
____________________ is a principle stating that the geologic processes operating today also operated in the past.
uniformitarianism
The major fuel in nuclear power plants is an isotope of ____
uranium
Water and air attack rocks at Earth's surface in a process called ____________________
weathering
Placer ore deposits form:
when streams or waves sort sediment according to density
An active continental margin forms:
where an oceanic plate sinks beneath a continental plate at a subduction zone
The three environments of magma production are ____________________ ____________________, ____________________ ____________________, and ____________________ ____________________
spreading centers, mantel plumes, and subduction zones
____________________ is the color of a fine powder of a mineral.
streak
Where two lithospheric plates of different densities converge, the denser one sinks into the mantle beneath the other in a process called ____
subduction
The Ring of Fire, a zone of concentrated volcanic activity encircling the Pacific Ocean basin, is located adjacent to ____
subduction zones
island arcs grow from ____
submarine volcanoes near a subduction zone
Earth's surface systems are ultimately powered by the ____.
sun
The fact that sedimentary rocks usually become younger from bottom to top is the principle of ____________________
superposition
Which one of the following is not a mineral?
synthetic diamond
A ____ is a combination of interacting components that form a complex whole.
system
A/An ____________________ is any combination of interrelated, interacting components.
system
The Earth's outer, cool, rigid shell is broken into several segments called ____________________ ____________________.
tectonic plates
Sand, silt, and clay that erodes from the continents and is carried to the deep sea floor is called ____
terrigenous sediment
____________________ defines the size, shape, and arrangement of igneous mineral grains in a rock
texture
a mineral is
the building blocks of rocks; a naturally occurring inorganic solid with a characteristic chemical composition and a crystalline structure; natural gems
The likely source of the Earth's magnetism is:
the flow of liquid metals in the outer core
The fundamental source of energy that drives Earth's surface systems¾the atmosphere, hydrosphere, and biosphere¾is:
the sun
The half-life of a radioactive isotope is:
the time it takes for half the atoms of the radioactive isotope in one sample to decay
Geologists use radioactive elements in rocks mainly to identify:
their absolute age
Imagine that a system has been perturbed at a constant rate for a long time, but the system has barely changed. Suddenly, a small additional perturbation causes a large change in the system. This scenario is an example of:
threshold effect
The San Andreas Fault is an example of a/an ____________________ plate boundary
transform
Where two plates move horizontally toward each other, they form a ____ boundary
transform
Which of the following tectonic environments does not generate large quantities of magma?
transform boundaries
A continental shelf on a passive margin is usually a wide bathymetric feature
true
A single plate can carry both oceanic and continental crust
true
A solar cell produces electricity directly from sunlight
true
A tsunami, produced by an undersea earthquake, may travel at 750 kilometers per hour
true
All of Earth's spheres continuously exchange matter and energy.
true
An element cannot be broken into smaller substances by ordinary chemical processes.
true
At present, the Atlantic Ocean is growing, while the Pacific is shrinking
true
Basaltic magma forms at the Mid-Oceanic Ridge
true
Earthquakes can occur in plate interiors
true
Gold and silver are examples of native elements.
true
Most rock-forming minerals are silicates.
true
Some of the world's richest offshore petroleum reserves are found on continental shelves
true
The Earth's atmosphere acts as a blanket, retaining heat at night and dispersing direct solar heating during the day.
true
Liquid freshwater amounts to about ____ percent of Earth's total water.
.64
The part of oceanic crust made up of pelagic and terrigenous sediment is:
layer 1
The magma of andesite and diorite contains ____________________ silica than granite
less
The age of the oldest ocean floor is about ____ million years
200 million
Average oceanic crust is ____ kilometers thick, whereas average continental crust is ____ kilometers thick.
4 to 7; 20 to 40
Geologists estimate that Earth formed ____ years ago.
4.6 billion
The mantle makes up about ____ percent of the Earth's volume
80
Oceans contain ____ percent of the Earth's water.
97.5
The earliest forms of rocks have been found in the _____ Eon.
Archean
Gradualism states that:
geologic change occurs over long periods of time by a sequence of almost imperceptible events.
In a placer deposit, gold settles out first when the stream current slows down because:
gold is denser than any other mineral
Two ore minerals that are commonly comprised of pure metals and contain only a single element are native ____ and ____.
gold, silver
Continental crust is typically of ____ composition
granite
The most catastrophic volcanic explosions occur when ____ reaches the Earth's surface
granitic magma
A seismograph measures ____
ground vibrations
The outer 75 to 125 kilometers of the Earth, including both the crust and upper mantle, consists of:
hard, strong rock of the lithosphere
The Hawaiian Island chain is an example of a volcanic center at a/an ____________________ ____________________
hot spot
The ____________________ contains all of Earth's water.
hydrosphere
Metamorphic rock forms when:
igneous, sedimentary, or other metamorphic rocks change because of high temperature and/or pressure, or compositional changes, or are deformed during mountain building
To measure the distance from a recording station to an earthquake epicenter, geologists evaluate the ____ with a time-travel curve
interval between the arrival of S and P waves
The metallic core is composed of ____________________ and ___________________
iron; nickel
A synthetic diamond is not a true mineral because it ____.
is not formed by natural processes
____________________ are atoms of the same element that have the same number of protons but different numbers of neutrons
isotopes
A/An ____________________ is a naturally occurring inorganic solid with a characteristic chemical composition and a crystalline structure.
mineral
The ____ scale measures the total amount of energy released during an earthquake, based on the amount of movement and the fault surface area
moment magnitude
A magmatic intrusion cutting through sedimentary layers:
must be younger than these sedimentary layers
____ releases no sulfur when burned, has a higher net energy yield than other fossil fuels, and can be extracted and used without refining
natural gas
The atmosphere consists mainly of ____.
nitrogen and oxygen
____________________ is any rock sufficiently enriched in one or more minerals to be mined
ore
The principle of ____ states that most sediment is deposited as nearly horizontal beds
original horizontally
The two most abundant elements in Earth's crust are ____.
oxygen and silicon
Continental crust and oceanic crust firmly join together at a/an:
passive continental margin