6.10A Layers of Earth

Plasticity

A characteristic of the material in the asthenosphere; existing in a solid state yet having the ability to flow without being a liquid.

Physical Properties

Characteristics that can be observed or measured; for example, color, melting point, and conductivity.

Density

Density is the amount of matter in a given space or volume; it is a relationship between mass and volume. Less dense matter will form layers above denser matter.

States of Matter

Distinct forms of matter known in everyday experience: solid, liquid, and gas; also referred to as phases of matter.

Pressure

Pressure is a variable that affects the state of matter of Earth's layers. Thick layers of rock apply great force to those layers buried below them, affecting the melting points of the buried rock.

Temperature

Temperature is a variable that affects the state of matter of Earth's layers. Layers of rock at greater depths from Earth's surface have more thermal energy.

Lithosphere

The cool, rigid, outermost layer of Earth that consists of the crust and the uppermost part of the mantle; broken into pieces or segments called plates.

Earth's Layers

The divisions of the composition of Earth determined by either chemical composition or by the physical state of matter.

Chemical Composition

The elements that make up a substance.

Outer Core

The outer layer of Earth's core; surrounds the inner core and is made of liquid nickel and iron.

Mantle

The solid layer of Earth between the crust and the core; made of dense silicates.

Asthenosphere

The solid layer with plasticity in the upper mantle that is located just below the lithosphere; lithospheric plates "float" and move on this layer.

Inner Core

The sphere of solid nickel and iron at the center of Earth; surrounded by the liquid outer core.

Crust

The thin, solid outermost layer of Earth; made of less dense silicates and is either continental (landmasses) or oceanic (ocean floors).