Earthquakes are difficult to predict because they result from rocks suddenly sliding past one another or breaking, and this varies across rock types.

Tectonic earthquakes are caused by tectonic plates sliding past one another at fault zones, deforming rock through friction as energy builds like a stretched rubber band.

Earthquakes of identical magnitudes are unlikely to cause equal damage because magnitude only measures energy released, and earthquake severity depends on environmental factors, such as local architecture and geological conditions.

Convection flows in Earth’s mantle drive the movement of tectonic plates

Earth's inner structure is a dynamic system of layers in constant, slow motion

The frequency of earthquakes and the distribution of their magnitudes have not changed significantly over long-term records, but technological improvements have enabled scientists to detect more of them as they occur.

Scientists investigate Earth's interior by studying seismic waves

What makes the Earth shake?

Eruption forecasting relies on probabilistic methods resembling weather forecasting

Explosive volcanic eruptions happen when magma pressure overcomes rock strength

Just as light bends at different angles as it travels through different materials, seismic waves move in different directions through Earth's interior, revealing the presence of layers with varying properties.

View maps of seafloor topography, earthquakes, and volcanic activity, which scientists use to create outlines of Earth's tectonic plates.

Reported earthquake magnitudes often change because initial values are based on limited information, whereas revised magnitudes account for factors such as fault size, rupture duration, and seismic wave behavior.

How we know what's deep inside the Earth, despite never traveling there

Simulate geological activity at plate boundaries using virtual planetary models.

Some earthquakes can produce smaller tremors called boomerang earthquakes, which travel in the opposite direction and ripple back to the original earthquake's source.

Rather than predicting them in advance, earthquake early warning systems detect tremors moments after they begin and send notifications that reach users before the seismic activity does.

Although earthquakes cause about 80% of tsunamis, almost all earthquakes lack sufficient energy to cause the sudden shift in the ocean floor needed to substantially displace enormous volumes of water.

Earth's major tectonic plates make up 95% of its surface

Some tectonic plates move faster than their underlying convection currents

The San Andreas Fault is an example of tectonic plates sliding past each other

Scientists determined that tectonic plates moved the ocean floor by observing symmetric patterns of magnetic stripes on opposite sides of underwater volcano systems, which could only result from seafloor spreading.

Scientists can map Earth's shape and structure by measuring the ratios of certain particles arriving from different directions in space, as these ratios change with the density of the material particles travel through.

200 million years of tectonic plate movement

Instead of the tectonic plates found on Earth that produce earthquakes, volcanoes, and other geological activity when they interact, Mercury, Mars, and the moon have continuous, unbroken shells of rock called 'stagnant lids.'

Solid ground can behave like a liquid during earthquakes, causing objects to sink into or rise up from an otherwise rigid surface.

Scientists determine earthquake locations by comparing how long it takes different seismic waves to be detected at three stations around the world, from which an origin, or hypocenter, can be triangulated.

View a map of the world's major earthquakes from 1956 to 2022, which can be used to identify tectonic plate boundaries.

Deep-sea trenches form when one tectonic plate subducts another underwater

Volcanoes 'die' when their supply of magma runs out, if they are shifted away from their underlying magma reservoir, or if they get clogged by collapsing or their magma cooling back into rock.

Visualize the power and frequency of earthquakes across the moment magnitude scale, where a whole number increase corresponds to about 32 times more energy released.

Why starquakes may explain various phenomena associated with neutron stars

Enhanced geothermal power systems can trigger earthquakes by injecting fluid into rock, increasing subterranean pressure.

A 25-magnitude earthquake would release enough energy to destroy the sun, while a -15-magnitude quake is made whenever dust settles onto a table's surface.

Some scientists hypothesize that stressed rocks can discharge built-up static electricity in the form of lightning—a phenomenon known as fracto-luminescence, or earthquake lights.

The four types of seismic waves—vibrations that carry energy generated by geological events, such as earthquakes—are categorized as body or surface waves.

Geological tremors on the moon provide evidence that it is shrinking

After a landslide, repeat activity may follow the appearance of cracks, springs of water, or dirt, sand, and rocks tumbling down from scars—exposed portions of Earth where the initial landslide began.

View the past month of earthquakes worldwide with this digital globe, which displays data from the US Geological Survey.

Records of Earth's magnetic field on the seafloor validated plate tectonics

Ancient sunken plates may influence mantle convection and surface motion

Scientists define sea level as the elevation to which water would settle on Earth's surface, given the planet's gravitational field and rotation.

Heat slowly moves through Earth's mantle like softened wax

Because the Richter scale was calibrated to crustal and mantle properties in Southern California, seismologists have instead used the moment magnitude scale to quantify earthquakes since the 1970s.

While landslides are associated with the downward flow of unstable terrain, the term encompasses a variety of geological processes, which are distinguished by how the material moves and what materials are involved.

Likened to a car backfiring or a faraway cannon fire, skyquakes have been reported worldwide in Earth's atmosphere without any obvious cause.

The Ring of Fire, which spans 40,000 kilometers (24,900 miles) around the Pacific Ocean, is the most geologically active region on Earth.

Magnetic material in rocks provides evidence of flips in Earth's magnetic field

Climate models use complex equations and supercomputers to predict future climate

If, not when: An earthquake is destined to destroy the Pacific Northwest.

Slab pull and ridge push contribute to convection-driven oceanic crust movement