Earth's Structure: Plate Tectonics - Seafloor Spreading
Terms in this set (20)
an underwater moutain chain where new ocean floor is formed
the process by which new oceanic crust forms as magma rises towards the surface and solidifies
a deep valley along the ocean floor beneath which oceanic crust slowly sinks toward the mantle
the process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary.
Earth's magnetic field reverses direction
a device that determines the distance of an object under water by recording echoes of sound waves
circular movement of a substance due to changes in temperature and density
a physical property; a measure of how much mass is contained in a given volume.
a force of attraction between objects that is due to their masses.
lava that cools underwater, taking on a distinctive pillow-like shape as it hardens
Collected body of data from observations and experiments
a cylindrical section of rock brought up from drilling show youngest rocks are the closest to the mid-ocean ridges & the rocks age as you move away in both directions
parallel patterns in the magnetic signature of rocks on either side of a mid-ocean ridge
a destructive plate boundary where oceanic crust is forced or sinks due to gravity into the mantle beneath a second plate.
a linear-shaped lowland between several highlands or mountain ranges caused by a rift or fault
lava that erupts along a mid-ocean ridge that cools and crystallizes; dominant rock of oceanic crust
a state in which magnetized objects orient north
a state in which magnetized object would reverse direction and point south
the rigid outermost layer of Earth that includes the upper mantle and crust
the partially melted portion of the mantle below the lithosphere