Structure and composition of the earth

Geothermal Gradient

The rate at which the Earth's temperature increases with depth, estimated at about 2.5 degrees per 100 meters.

Kola Super Deep Borehole

The deepest borehole in the world, located in Siberia, measuring more than 12 kilometers deep.

Peridotite

A dense, ultramafic rock that is lower in silica and rich in metals like magnesium and iron, often found in volcanic eruptions.

P Waves

Primary waves that are compression waves traveling faster than S waves and can move through solids and liquids.

S Waves

Secondary waves that are shear waves, slower than P waves, and cannot travel through liquids.

Moho Discontinuity

The boundary between the Earth's crust and the underlying mantle.

Lithosphere

The rigid outer part of the Earth, consisting of the crust and uppermost mantle, which makes up tectonic plates.

Asthenosphere

The upper part of the mantle, situated beneath the lithosphere, that behaves plastically and allows for movement over geological time.

Gutenberg Discontinuity

The boundary between the Earth's mantle and outer core.

Curie Point

The temperature above which certain materials lose their permanent magnetic properties, relevant to understanding the Earth's magnetic field.

Chondrite Meteorites

Meteorites that are rich in iron, carbon, and water, believed to be primordial material from which the Earth formed.

Iron Meteorites

Meteorites consisting mostly of iron and nickel, thought to originate from the cores of differentiated bodies in the early solar system.

Seismic Wave

Waves of energy caused by earthquakes that travel through the Earth's layers, providing information about its interior structure.

Seismograph

An instrument that records the motion of the ground during an earthquake, capturing seismic waves.

Shadow Zone

Regions of the Earth where seismic waves do not arrive due to being refracted by different materials.

Density

Mass per unit volume, important for understanding the classification of Earth's layers.

Earth's Core

The innermost part of the Earth, consisting of a liquid outer core and solid inner core, primarily composed of iron and nickel.

Seismic Wave Refraction

The bending of seismic waves as they pass through materials of different densities.

Earthquake

A sudden release of energy in the Earth's crust that causes seismic waves.

Seismic Waves

Energy waves that are produced by the movement of faults during earthquakes, which include P waves, S waves, and surface waves.