Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/43

Click to flip

43 Cards in this Set

  • Front
  • Back
galaxy
a large group of stars held together by gravity
Milky Way
Our outer galaxy
spectrum
a band of colors made when white light is broken up
expansion redshift
the shift of a spectrum of a galaxy toward longer(redder)wavelengths due to the expansion of space
big bang
the beginning of the universe, when the density of the universe was very high
background radiation
electromagnetic radiation left over from the big bang
quasar
an extremely bright, extremely distant, high-energy source
crust
Earth's solid, rocky surface containing the continents and ocean floor
original horizontality
the idea that many kinds of rocks form in flat, horizontal layers
continental drift
the idea that a supercontinent split apart into pieces, the continents, which drifted in time to their present locations
sea-floor spreading
the idea that new crust is forming at ridges in the sea floor, spreading apart the crust on either side of the ridges
magma
hot,molten rock below Earth's surface
plate tectonics
the idea that Earth's surface is broken into plates that move
mantle
Earth's layer beneath the crust
subduction
where plates collide, the sliding of a denser ocean plate under another plate
fault
a huge in the crust, at or below the surface, the sides of which may show evidence of motion
focus
the point where an earthquake starts, where rocks begin to slice past each other
seismic wave
a vibration that spreads out away from a focus when an earthquake happens
epicenter
the point on Earth's surface directly above the focus
aftershock
the shaking of the crust after the the initial shaking of an earthquake
seismograph
a sensitive device that detects the shaking of the crust
magnitude
the amount of energy released by an earthquake
hot spot
a very hot part of the mantle, where magma can melt through a plate moving above it
vent
a central opening in a volcanic area through which magma may escape
lava
magma that reaches Earth's surface and flows out of a vent
crater
a cuplike hollow that forms at the top of a volcano around the vent
cinder-cone volcano
a steep-sided cone that forms from e eruptions of hot rocks, ranging from particles to boulders
shield volcano
a wide, gently sloped cone that forms from flows of lava
composite volcano
a cone formed from e eruptions of hot rocks followed by a flow of lava, over and over
geothermal energy
heat from below Earth's surface
fold mountain
a mountain made mostly of rock layers folded by being squeezed together
fault-block mountain
a mountain made by huge tilted blocks of rocks separated from surrounding rocks by faults
weathering
the breaking down of rocks into smaller pieces by natural processes
erosion
the picking up and removal of rock particles
soil
a mixture of weathered rock, decayed plant and animal matter, living things, air, and water
soil horizon
any of the layers of soil from the surface to the bedrock below
groundwater
water that soaks into the soil and rock by collecting in spaces between rock particles
humus
material in soil formed by the breakdown of plant and animal material
mass wasting
the downhill movement of Earth material caused by gravity
desposition
the dropping off of sediment
glacier
a huge sheet of ice and snow that moves slowly over the land
till
a jumble of many sizes of sediment deposited by a glacier
moraine
a deposit of many sizes of sediment in front of or along the sides of a glacier