Seafloor Spreading Essentials Concept Review
convection currents
seafloor spreading and plate tectonics theory is driven by this process occurring in the Earth's mantle
oceanic
Because of the process of subduction at trenches, this type of crust is younger than the other type (choose continental or oceanic crust is younger)
younger
EVIDENCE: The age of the seafloor at the mid-ocean ridge is (younger/older) than the age of the seafloor farther from the mid-ocean ridge
older
EVIDENCE: The age of the seafloor farther away from the mid-ocean ridge is (younger/older) than the age of the seafloor closer to the mid-ocean ridge.
magnetic field
EVIDENCE: The reversal of Earth's _____________ is recorded in the pattern of the seafloor
magma
EVIDENCE: This material has been observed erupting along mid-ocean ridges, forming new seafloor.
younger
Since old seafloor subducts into trenches the ocean crust is (younger/older) than continental crust
growing
The Atlantic ocean, with the mid-Atlantic ridge and just a few small trenches, is (growing/shrinking)
shrinking
The Pacific Ocean with numerous trenches along the Ring of Fire is (growing/shrinking)
granite
continental crust is primarily made of this type of igneous rock
more dense
oceanic crust subducts under continental crust because it is (more dense or less dense?)
seafloor spreading
process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.
subduction
process where denser oceanic crust sinks under another plate back into the mantle at a trench.
magnetic stripes
The pattern of these on the seafloor is identical on either side of the ridge.
continental drift
The process of seafloor spreading helped support/prove what theory?
seafloor spreading
What is the process occurring in this diagram?
subduction
What process is occurring in this picture where the ocean crust is meeting the continental crust?
mid-ocean ridge
long underwater mountain chains where new ocean crust is formed
trench
oceanic crust is "recycled" in the mantle when it subducts at this feature
basalt
oceanic crust is primarily made of this type of igneous rock
magma
what is the orange/red material in the diagram?
convection
what process is occurring in the mantle in this diagram?