what is the crack in the ocean floor through magma rises?
According to wegener, what happen about 250 million years ago?
the supercontinent began breaking into smaller continents
tectonic plates are blocks of
at the center of a mid-ocean ridge is a(n)
The composition of Earth's interior affects
the speed and direction of seismic waves
Which scale more accurately measures the magnitude of large earthquakes?
moment magnitude scale
If you are in a car during an earthquake, you should
stop the car in a safe place
what happens to tsunamis as they move toward shore?
They increase in height.
If you are indoors during an earthquake, you should
stay away from windows
Which of the following is NOT a cause of tsunamis?
If you ars indoors during an earthquake, you should
crouch under a desk.
How does the structure of Earth' s interior affect seismic waves?
It can affect the speed and direction of seismic waves
Which of the following are studied to forecast earthquakes?
seismic gaps foreshocks, rock changes
Why do earthquakes usually occur at plate baundaries?
Rock in environments near tectonic plate boundaries experience great stress.
S waves are also known as
Fault zones form at plate boundaries because
intense stress occurs there when the platesseparate, collide, subduct, or slide past each other.
What forms on the ocean floor in a subduction zone?
Volcanic eruptions rnay be signaled by
a change in earthquake activity
A large depression formed by the collapse of a volcanic cone is called a
Volcanic ash, dust, blocks, bombs, and lapilli ara all
The eruption of Mount St. Helens was
en explosive eruption
Three events that might signal a volcanic eruption aro rhanges in earthquake activity, volcano surface bulges, and
a change in gases emitted.
Modern oceanography began with
the HMS Challenger
Most mid-ocean ridges form
below sea level.
A piece of sediment collected by drilling is a(n)
The most common compounds in organic sediments are
silica and calcium carbonate.
To calculate the depth of the ocean floor with sonar, scientists measure
the time it takes sound waves to travel.
The source of most calcium carbonate in biogenic sediment is
Most oxygen enters the ocean from
What is called the foundation of life in the ocean?
The ocean is the main source of the trace minerals
magnssium and bromine.
Most offshore oil and petroleum deposits are found
along continental margins
In addition to increased use of toxic chemicals, what has reduced the ocean's ability to renew itself
increased world population
In addition to limitng the use of leaded gasoline, what has the United States done to reduce ocean pollution?
banned the toxic chermical DDT
Trace elements in the ooean are those minerals that are
smallest in amount.
Volcanic eruptions, chemical weathering of rock on land, ffid chemic,al rcactions between sea water and newly formed searfloor rocks providemost of the raw elements that form this dissolved solid in the ocsan.
Where would a tidal bore occur?
where a river enters the ocean
The curving of the path of ocean currents and wind belts is called
the Coriolis effect.
The force that causes tides is
Very large waves are usually the result of
a long fetch.
In the tropical latitudes, trade-wind belts push currents
Sandbars are formed by
As lower layers of air are warmed,
the air rises.
what air massss generally move eastward, toward Europe?
mantime polar Atlantic
A large body of air throughout which temperature and moisture content arc similar is a(n)
Continental polar, maritime polar, continental tropical, andmaritime tropical are types of
Doppler radar and satellite images provide information to create
A pattern of meteorological symbols that represent the weather at a particular observing station is a
When air movss slowly, in takes on the temperrture and humidity of its region, becoming a(n)
Lines that, connect points of equal temperature on a weather map are called
An air mass that originates in the Pacific or Atlantic Ocean and brings warm, moist air is called
What weather effsct results when a moving air mass hits a mountain, rises, cools, and loses most of its moisture through precipftrtion?
which of these climates is characterized by dense, lush vegetation; broadleaf plants ; and high biodiversity?
Climate does NOT change as a result of
general circulation models.
Which of the following is NOT an impact of climate change?
change in tida patterns
The average weather conditions for an area over a long period of time is referred to as the area's
Tree rings have been used to measure
hundreds to thousands of years
What is the name for the climate of a small area?
Which of the following rnay decrease temperatures by reflecting sunlight back into space?
When an air mass encounters a mountain range, the air mass
rises and cools.
What do high levels of carbon dioxide in an ice core indicate?
a warm climate
Computer climate models that incorporate millions of pieces of data and help sort complex sets of variables &re called
general circulation models
What do fossils of flower pollen and plants with broad leaves indicate?
What characteristic do the tropical savanna, and tropical rain-forest climates share?
a small temperature range
Which climate zone has an annual rainfall of less than 25 cm?
Specific heat is the amount of energy needed to change the temperature of 1 g of substance by
A telescope tha tuses a set of lenses to gather and focus light from distant objects is a
A constellation's change in position over several hours is caused by
Earth's revolution around the sun.
The Northern Hemisphere has the most hours of daylight at the
A light -yeat equals
9.46o7 x 10 12 km.
Invisible electromagnetic radiation was discovercd with a
One line of evidence of Earth's revolution around the sun is
the varying positions of a constellation wer a period of weeks.
What problem is solved by sending telescopes into space?
interference of Earth's atmosphere in detecting electromagnetic radiation
About 99% of all matter contained in the solar nebula now exists in
The two inner planets most alike in size, mass, and density are
Venus and Earth
The early atmosphere developed when many volcanic eruptions released large amounts of gases rn a process called
A rotating cloud of gas and dust from which Earth's solar system formed is called a(n)
is almost parallel to its plane of orbit.
When fast-moving planets pass slow-moving planets in their orbits, why does it appear as though planets that orbit more slowly than Earth are moving backward?
because of retrograde motion
The asteroid belt can be found between which two planets?
Mars and Jupiter
Small bodies from which planets ongrnated during the early formation of the solar system are called
An engineer examining photos discovered volcanoes on
Many comets in the Kuiper belt are the result of
collisions between large objects
Characteristics of Ganymede and Callisto are, respectively,
a magnetic field and craters.
Where is the Kuiper belt located?
beyond Neptune's orbit
Most of the sun's energy is a result of
Auroras ars frequently seen
after solar flares
Which of the following is NOT a solar ejection?
Sunspots vary in a cycle that lasts about
Einstein's equation E = mc2 helps scientists understerd the sun's energy because the equation
explains how mass can be converted into huge amounts of energy.
Scientists break up the sun's light rrto a spectrum using a device called a
Magnetic fields on the sun are produced by the sun's uneven rotation and
gases in the convective zone.
Hcw long would a star with the sun's mass stay on the main sequence?
10 billion years
After its temperature rises to 10,000,000"C, a protostar becomes a star when
nuclear fusion begins
What is a quasar?
quasi-stellar radio source
What is apparent magnitude?
the brightness of a star as it appears from Earth
An elliptical galaxy
contains few young stars, has little dust and gas, and is elongated.
Astronomers believe that cosmic background radratron formed