Sea Floor Spreading

Front 1

Sea floor spreading

Back 1

magma rises at the mid-oceanic ridge, Forming new crustal material and plated move apart

Front 2

Distribution of volcanoes

Back 2

occur at hot spots or convergent boundaries forming volcanic mountains or volcanic island arcs " ring of fire"

Front 3

Weight

Back 3

the pull of gravity on the mass of an object

Front 4

Mid-oceanic ridge

Back 4

World's longest mountain chain, the rift valley running down the center of the ridge is the site of new plate growth

Front 5

Thickness or the sediments on the ocean floor

Back 5

as you go from the mid-oceanic ridge the sediments get thicker and older

Front 6

Subduction zones

Back 6

a denser oceanic plate goes under either a continental plate or another less dense oceanic plate to move into the mants

Front 7

Trench

Back 7

surface feature of a subduction zone. deepest parts of the ocean

Front 8

ancient mountain chain

Back 8

Running from NE south america-NW africa-Eastern US across central scotland and into Scandinavia. This chain was considered evidence for continental drift and later plate tectonics

Front 9

magnetic reversals

Back 9

used to show pattern of rock formation around mid-oceanic ridges, reflected the reversal of magnetic north over millions of years

Front 10

Glacial evidence

Back 10

rock striations indicated a single continental glacier streching over africa, south america and madagascar, support for idea of continental drift and theory of plate tectonics

Front 11

role of sample size in density

Back 11

the amount of sample does not affect density because it is calculated to be mass per 1 unit of volume

Front 12

rocks

Back 12

naturally occurring, usually made of two or more minerals

Front 13

minerals

Back 13

crystalline structure, solid, naturally occurring, definite chemical makeup

Front 14

topographic map

Back 14

shows relief and surface features of an area using contour lines.

Front 15

fair test

Back 15

a repeatable procedure for manipulating only one variable in order to answer a question