7th grade science 11

Question 1

Continental drift

Answer 1

Wegener’s hypothesis that all continents were once connected in a single large landmass that broke apart and drifted slowly to their current positions

Question 2

Pangaea

Answer 2

A single landmass composed of all the continents joined together

Question 3

Sea floor spreading

Answer 3

Hess’s theory that magma under Earth’s crust is forced up towards the surface at the mid ocean ridges, forming new seafloor

Question 4

Asthenosphere

Answer 4

Plastic like layer of earth on which the lithosphere plates move

Question 5

Convection currents

Answer 5

Cycle of heating, rising, cooling, and sinking

Question 6

Lithosphere

Answer 6

Rigid layer of Earth made of the crust and upper mantle on the asthenosphere

Question 7

Plate

Answer 7

Large section of Earth’s crust layer and upper mantle layer that moves around on the asthenosphere

Question 8

Plate tectonics

Answer 8

Theory that Earth’s crust and upper mantle are broken into plates that move around on a plastic like layer of mantle

Question 9

Earthquake

Answer 9

Movement of the ground that occurs when rocks inside Earth reach there elastic limit, break suddenly, an experience rebound

Question 10

Epicenter

Answer 10

Point on Earth’s surface directly above the earthquakes focus

Question 11

Fault

Answer 11

Fracture that occurs where rocks break which results in movement of opposing sides

Question 12

Focus

Answer 12

Point deep inside Earth where energy is released, causing an earthquake

Question 13

Magnitude

Answer 13

Measure energy released by an earthquake

Question 14

Seismic safe

Answer 14

Describes the ability of structures to stand up against vibrations caused by an earthquake

Question 15

Seismic waves

Answer 15

Earthquake waves including primary waves, secondary waves, and surface waves

Question 16

Seismograph

Answer 16

Instrument used to record seismic waves

Question 17

Tsunami

Answer 17

Powerful seismic wave that begins over an ocean floor earthquake

Question 18

Cindercone volcano

Answer 18

Tivoli small volcano formed by moderate to explosive eruptions of tephra

Question 19

Composite volcano

Answer 19

Steep sided volcano formed with alternating layers of violent eruptions of tephra and quieter eruptions of lava

Question 20

Lava

Answer 20

Molten rock flowing onto earths surface

Question 21

Shield volcano

Answer 21

Large, broad volcano with gently sloping sides and is formed by the buildup of basaltic layers

Question 22

Volcano

Answer 22

Cone shaped hill or mountain formed when hot magma, solids, and gases erupt onto earths surface through a vent

Question 23

Hot spot

Answer 23

Large body of magma that has been forced upward from deep within the earth, which may cause volcanoes to form in the middle of a plate

Question 24

Rift

Answer 24

Long crack, fissure, or trough that forms between tectonic plates moving apart as tectonic boundaries