Workers excavating Hall’s Cave in Central Texas. Image Courtesy of Michael Waters

Cooling of Earth caused by eruptions, not meteors

Map of the Earth showing the present-day deviation from expected magnetic field direction. The star is Saint Helena

South Atlantic anomalies existed 8 – 11 million years ago

Earth

Study could rewrite Earth’s history

Earth magnetic field. Credit: Carnegie Institution for Science

How does Earth sustain its magnetic field?

Earth’s geomagnetic field

Earth’s magnetic field can change 10 times faster than previously thought

The composition of fossilised zooplankton shells has enabled the reconstruction of past pH and CO2. Credit: University of Southampton

By 2025, carbon dioxide levels in Earth’s atmosphere will be higher...

A new study shows that giant ore deposits are tightly distributed above where rigid rocks that comprise the nuclei of ancient continents begin to thin, far below the surface (white areas). Redder areas indicate the thinnest rocks beyond the boundary; bluer ones, the thickest. Circles, triangles and squares show known large sediment-hosted deposits of different metals. (Adapted from Hoggard et al., Nature Geoscience, 2020)

Geologists identify deep-earth structures that may signal hidden metal lodes

Our planet has a layered structure of silicate mantle and metallic core. The liquid outer core is located 2900 km below the surface where the pressure and temperature are extremely high, >136 gigapascal (1.36 million atmospheres) and >4000 C. The sound speed and density profiles of the deep-interior of our planet is given by seismological observations.

Precise measurement of liquid iron density under extreme conditions

Earth

Uncovering the two ‘faces’ of the Earth

Scientists examined hundreds of samples taken along the global ridges that contain recycled ancient oceanic crust in variable amounts. "Depleted" segments of the ridge received lower than "normal" amounts of recycled crust, while "enriched" segments contain a larger proportion of recycled crust.

Geochemists solve mystery of Earth’s vanishing crust

Mud Volcanoes

The geological record of mud deposits

A lump of coal weathering out from Siberian flood basalts in a quarry near the town of Ust Ilimsk Credit: Scott Simper

Coal-burning in Siberia led to climate change 250 million years ago

Earthquakes send sound waves through the Earth. Seismograms record the echoes as those waves travel along the core-mantle boundary, diffracting and bending around dense rock structures. New research from University of Maryland provides the first broad view of these structures, revealing them to be much more widespread than previously known. Credit: Doyeon Kim/University of Maryland

Scientists detect unexpected widespread structures near Earth’s core

New Curtin University research on the remixing of Earth's stratified deep interior suggests that global plate tectonic processes, which played a pivotal role in the existence of life on Earth, started to operate at least 3.2 billion years ago. Credit: Professor Zheng-Xiang Li

Remixed mantle suggests early start of plate tectonics

The Brooks Range stretches across northern Alaska. Boreal forests in North America are among the largest areas experiencing a relatively low human impact. (Jason Riggio/UC Davis)

Half the earth relatively intact from global human influence

If ice once covered the entire planet, how did the transition take place and what does it say about Earth's climate? Credit: NASA Goddard photo

Researchers unlock clues to a dramatic chapter of Earth’s geological history

Study proves that magma chambers are huge masses of crystals with...

A schematic diagram of the Earth's deep oxygen factory shows the oxygenation and deoxygenation processes of hydrous mantle materials in the lower mantle across the ~1000 km depth beneath Earth's surface. Under the conditions of Earth's middle mantle, scientists discovered an oxygen-excess phase, (Mg,Fe)2O3+δ (0 < δ < 1) that can be formed with under-saturated water at >1000 kilometers depths. Those oxygen-excess materials may have long-termly oxidized the shallow mantle and the crust, which is essential to allow free oxygen to build up in Earth's atmosphere. Credit: Science China Press

Oxygen-excess oxides in Earth’s mid-mantle facilitate the ascent of deep oxygen

Earth

Earth’s lower mantle can be oxidized in the presence of water

The rising Earth from the perspective of the moon.

Project aims to create first 4-D maps of Earth’s mantle

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