How the Earth Works

Investigating the dynamic nature of Earth.

Determining the precise age of Earth entailed centuries of investigative efforts.

A modern-day journey to the center of the Earth in the style of Jules Verne.

Exploring the phenomena of heat radiation, conduction and convection.

The theory of plate tectonics accounts for many aspects of the planet.

Investigating the early evolution of the universe to learn the origin of atoms, stars and planets.

The solar system formed when a cloud of gas, dust and ice began to collapse and rotate.

While rocks may seem eternal, they participate in a continuous cycle of changing forms.

Rocks are made of minerals, which in turn are composed of elements.

Magma forms beneath mid-ocean ridges through a process known as pressure release.

When magma cools below certain temperatures, solid mineral crystals begin to grow.

Volcanoes form where magma reaches the surface and erupts — at which point the magma becomes lava.

Exploring how rocks deform in an elastic, plastic or brittle manner.

Examining the faults along which earthquakes occur and the aftermath.

Two main forces are directly responsible for plate motions: slab pull and ridge push.

The seafloor shows a diversity of features related to plate tectonics and mantle convection.

Oceans undergo reincarnation: they repeatedly die and are reborn.

Transform faults are rare on land, but mid-ocean ridges are intersected by countless such features.

Subduction zones are the most geologically exciting places on Earth.

Plate motions bring continents into contact; the result is the formation of mountains.

Recent work reveals that Earth has many ways of making a volcano.

The human consequences of large earthquakes and volcanic eruptions.

Monitoring volcanoes is feasible, unlike earthquakes, which remain unpredictable.

Examining the eruption of Mount St. Helens on May 18, 1980.

The complex tectonic forces behind this cataclysm.

Tectonic plates move through the geologic record, observed by scientists for countless years.

North America has continuously grown through collisions with other continents.

Plate tectonics creates mountains, erosion tears them down.

Exploring Earth's uniqueness in the solar system for having liquid water at its surface.

Exploring the structure of the atmosphere and its circulation.

Exploring why a mountain on the Moon can last for billions of years, but not a mountain on Earth.

Six large convecting cycles control the distribution of precipitation and therefore of ecosystems.

Once rock is broken into sediment, gravity makes sure that it heads downhill.

Once sediment erodes and moves downhill, streams do most of the work from there.

There is 100 times more water in the ground than in streams and lakes combined.

Shorelines are energetic environments where wave energy erodes rock.

Glaciers are slowly moving rivers of flowing ice.

Cold glacial periods alternate cyclically with warmer interglacial phases.

Long timescale variations in climate are controlled predominantly by plate tectonics.

Exploring climate change on timescales of decades to thousands of years.

The course of human civilization is strongly tied to small changes in global and regional climates.

Exploring why there is gold in California, coal in Indiana and oil in Iraq.

Humans predominantly use nonrenewable energy sources.

All the energy will be provided by solar-driven sources.

Humans have become Earth's most powerful agent of geologic change.

The path of evolution has been an integral part of Earth's story.

Although Earth is unique for having complex life, it is not unique in geologic processes.

Exploring the chances that there are other civilizations in the galaxy.