Geology 114- Ch 1 & 2

The Geosphere

the geosphere is the largest of the earths 4 spheres. it includes continental and oceanic crust as well as the varius layers of earths interior

Granite

Continental crust usually contains a rock that is made up of less dense elements, called Granite.

The Core

Core has two parts. Solid inner core which is composed of solid iron and some nickel. The liquid outer core, which makes up a third of the Earth's mass.

Outer Core

Outer core is liquid because the pressures are slightly lower in this region, but the temperatures are still high enough to be above the melting point of iron.

The lower mantle

Solid rock that gradually increases in density downward toward the boundary with the molten material of the outer core. Higher pressures at lower mantle are thought to make the minerals denser than those of the upper mantle.

The lithosphere

Sub-section of the upper mantle, directly above the asthenosphere. Shallowest physical layer. Made up of strong, rigid rocks that can break when they move. Contains rigid rocks of the oceanic crust, the continental crust, and the top portion of the underlying upper mantle.

The asthenosphere

Sub-section of the upper mantle, directly below the lithosphere. Mostly solid but pliable (like putty) and can flow under pressure. Weaker than laters above or below it, rocks are very close to their melting point in the asthenosphere (some parts may be molten). Slow seismic waves.

Continental Crust

The crust that makes up the Earth's landmasses and their shallowly-submerged edges. Composed mainly of less dense elements (calcium, sodium, potassium, aluminum, silicon, and oxygen)(Granite)

Inner Core

Inner core is very dense and solid in spite of extremely high temperatures because of the very high pressures at the Earth's center

The upper mantle

Lies above the transition zone and extends upward to the base of the crust. Upper mantle is divided into the asthenosphere and the lithosphere.

The Mantle

Most of the Earth's interior consists of the mantle (67% of the Earth's total mass). Has some internal variations in composition but is mostly magnesium, silicon, oxygen, and iron.

Minerals

Naturally occurring solids with an orderly arrangement of atoms and distinct chemical compositions

The Crust

The outer thin skin of the Earth. There are two fundamentally different types of crust: Continental and Oceanic.

The mantle transition zone

The transition done is the part of the mantle where rocks like those in the upper mantle are being transformed into rocks like those in the lower mantle

Oceanic Crust

Underlies the ocean. Thin, iron-rich, and young compared to continental crust. (Iron, magnesium, calcium, silicon, and oxygen). Oceanic crust consists primarily of volcanic rock called basalt--which is formed from partially melted mantle that migrates to the Earth's surface at seafloor volcanoes.

Basalt

Volcanic rock, formed from partially melted mantle that migrates to the Earth's surface at seafloor volcanoes. It is the most abundant volcanic rock, fender on average than rocks of the continental crust because it contains more iron and magnesium.

Density

mass per unit volume (can be measured with the testing of the velocity of seismic waves that pass through it since seismic waves travel faster through denser material)