the gradual movement and formation of continents (as described by plate tectonics)
when two tectonic plates push into one another, the boundary where they meet.
a deep valley along the ocean floor through which oceanic crust slowly sinks toward the mantle.
A plate boundry where two plates move away from each other
When fossils have the magnetic polarity of the time during which they were formed. They provide us with a way to see where the magnetic poled were at various times in the past.
an area where magma from deep within the mantle melts through the crust above it
A string of islands formed by the volcanoes along a deep ocean trench, a chain of volcanic islands formed at an ocean-ocean convergent boundar
a switch in the direction of Earth's magnetic field so that the magnetic north pole becomes the magnetic south pole and the magnetic south pole becomes the magnetic north pole.
Oceanic ridge system
A system of continuous elevated zones on the floor of all major ocean basins and varying in width from 500 to 5000 km (300 to 3000 mi). The rifts at the crests of ridges represent divergent plater boundaries.
The study of the alignment of magnetic minerals in rock,specifically as it relates to the reversal of Earth's magnetic poles; also the magnetic properties that rock requires during formation
(plate tectonics) a hypothetical continent including all the landmass of the earth prior to the Triassic period when it split into Laurasia and Gondwanaland
a rigid layer of the Earth's crust that is believed to drift slowly
the study of large scale movement and deformation of the earth's outer layers in terms of rigid plates over a partly molten layer of the upper mantle
the process in which new material at a ridge or rift pushes older material aside, moving the tectonic plates away from the ridge
a deep valley that forms where two plates move apart
The process that creates new sea floor as plates move away from each other at the mid-ocean ridges
The pulling of a tectonic plate as its edge subducts deep into the mantle. Primary force of plate tectonics
Transform fault boundary
a boundary in which two plates slide past each other without creating or destroying lithosphere
Volcanic island arc
a chain of volcanic islands generally located a few hundred kilometers from a trench where there is active subduction of one oceanic plate beneath another