Quizlet #11

Continental Crust

the earths crust that is made up largley of granite and granodiorite.

Plate Boundry

a place where one tectonic plate ends and another begins

Divergent Boundaries

a place where two of Earhs tectonic plates are moving apart; is associated with volcanism, earth quakes, and high heat flow, and is found primarily on the ocean floor.

Convergent Boundaries

a place where two of Eaths tectonic plates are movinnd high heat flow apart: is associated with volcanism earthquakes, is primarily on the ocean floor.

Transform Boundry

a place where two tectonic plates slide horrizontal past eachother; is characterized by long faults and shallow shallow earthquakes.

Subduction

a process by which one tectonic plate slips beneath another tectonic plate.

Ridge Push

a tectonic plate process associated with convection currents in the earths mantle that occurs when the weight of an elavated ridge pushes toward a subduction zone.

Slab Pull

a tectonic process associated with the convection currents in the Earths mantle that occurs as the weight of the subducting plate pulls the trailing lithosphere into the subduction zone.

Mantle Convection

heat transfer and movement within the plastic like portions of the mantle caused by the tendancy of hotter and therfore less dense, material to rise, and colder material to sink

Tectonic Plates

huge pieces of the lithosphere (crust and upper mantle) that cover the earths surface and fit together at their edges. often times these are called lithosphere.

Core

the central part of the earth below a depth of 2900 km. It is thought to be composed of iron and nickel and to be molten on the outside with a central solid inner zone

Oceanic Crust

the earths crust that makes up the ocean floor that is mostly made out of basalt.

Mantle

the main bulk of solid earth between the crust and the core, ranging from depths of 40km to 2900km. It is composed of dense mafic silicate minerals and divided into different layers by phase changes that are caused by an increase in pressure with depth.

Lithosphere

the outer, rigid shell of the earth, situated above the asthenosphere, and containing the crust, and the uppermost mantle. the tectonic plates are made up of the lithosphere.

Plate Tectonics

the theory and study of plate formation, movement, interaction, and destructio; the attempt to explain earthquakes, volcanism, mountain building, and evidence of paleomagnetism in terms of plate motions

Asthenosphere

the weak layer below the lithosphere on which the plates "Float". this layer is a part is a part of the mantle and is solid, but it has the ability to flow like a soft plastic.

Crust

the outermost layer of the earth consisting of the relativley light, low melting point materials.