1.2 Plate Tectonics Flashcards
Theory of plate tectonics
A theory developed in the 1960s that helps explain the formation of some of the important features on Earth’s surface and how the continents move.
Convection current
The transfer of thermal energy (heat energy) by the motion of a fluid.
tectonic plates
large sections of crust
supercontinent
a large land mass thought to have broken up into several of the current continents
Pangea
It is what the supper continent is called.
divergent plate boundary
Two tectonic plates move apart, forming new land between them.
convergent plate boundary
Two tectonic plates move towards each other.
Transform plate boundary
Two tectonic plates try to slide past each other.
Lava
Molten rock that erupts from the Earth’s crust
Earthquake
A sudden shaking of the ground is usually caused when two plates suddenly slip against each other.
Volcanic islands
Islands formed when volcanic eruptions result in the formation of an island or group of islands.
volcanoes
Part of the Earth’s crust from which lava erupts
mid-ocean ridge
Mountain ranges formed deep in the ocean that extend for hundreds of miles either side of the parting plates.
hydrothermal vent
Cold ocean water seeps into the Earth’s crust and is superheated by underlying magma; this heated water is forced through vents(gaps) in the ocean floor and as it cools dissolved minerals solidify and form a chimney-like structure
minerals
Nutrients that are needed by living organisms, examples include calcium and iron
subduction
the downward movement of one plate beneath another
tsunami
a fast-moving wave with a long wavelength, created by ocean floor displacement or landslide
melt
The change of a solid into a liquid; during this process, heat is taken in from the surroundings.
ocean trench
a deep underwater valley formed when oceanic crust slides below continental crust
continental shelf
part of the continental plate extending from coast/shore in shallow waters with little or no slope
sediments
Small fragments of rock, such as gravel, sand and silt.
breakwater
A barrier which reduces the energy in waves before waves reach the coast
ecosystem
all the organisms in the area, along with their environment
tourism
Recreational visits to an area that brings money into local economies