sci 3 Flashcards
the outermost layer of the geosphere.
crust
The boundary between the Earth’s crust and mantle is called the
Mohorovičić discontinuity.
The crust, together with the uppermost part of the mantle, make up the brittle lithosphere,
which is broken up into major sections called
tectonic plates.
The abundance of elements on the crust was studied using its —-.
rock
are abundant elements found on Earth’s crust.
Oxygen, silicon, aluminum, and iron
The most abundant element in Earth’s crust is
oxygen
being the second most common element, exists as a compound in the mantle and
crust.
Silicon,
comes third at 80 700 ppm. Like silicon, it exists as a compound in the crust. This
element is extracted from its compounds commonly through the Bayer and Hall-Heroult
processes. It is a lightweight metal used in making utensil foils and packaging materials.
Aluminum
extracted from iron ores such as hematite and magnetite. It exists in Earth’s crust
with a composition of 41 000 ppm. It has many applications, one of which is for the
production of steel.
iron
separate continental crust from oceanic crust.
Continental margins
are the areas found between the continental margins and ocean ridges.
Deep ocean basins
ocean ridges are composed of.
newly formed oceanic crust which has been uplifted and faulted
The age of oceanic crust is approximately
180,000 million years old or less.
two types of crust
oceanic and continental crust
Oceanic crust is composed
mostly of
dark-colored mafic rocks.
is composed of many rock types. Its major
component is granodiorite, a light-colored igneous rock.
continental crust