back to top
27.8 C
New York
Sunday, February 23, 2025
Home Earth Page 5

Earth

Latest
Brazilian emeralds in a quartz-pegmatite matrix. (Photo courtesy of Madereugeneandrew/Wikimedia Commons)

Earth grows fine gems in minutes

Pioneering new research has helped geologists solve a long-standing puzzle that could help pinpoint new, untapped concentrations of some the most valuable rare earth deposits. Credit: Michael Anenburg, ANU.

Geologists solve puzzle that could predict valuable rare earth element deposits

A rough diamond from Kankan, Guinea, that was analyzed in a new study led by a PhD student at the U of A. The imperfections inside the diamond are small inclusions of a mineral called ferropericlase, which is from the lower mantle. Credit: Anetta Banas

Uncovering new understanding of Earth’s carbon cycle

carbon cycle

Understanding Earth’s ‘deep-carbon cycle’

Enhanced map of hematite (red) on Moon using a spheric projection (nearside only). Credit: Shuai Li

Has Earth’s oxygen rusted the Moon for billions of years?

Basalt, the most-common rock on Earth’s surface, encases green crystals--a geologic "nesting doll" phenomenon called a xenolith. Basalts such as this one derive from a section of the mantle that has been depleted in incompatible trace elements, which is usually attributed to continental crust formation. In their work, Tucker and his collaborators propose another mechanism that would impart this signature. Credit: Carnegie Institution for Science

Probing the origin of the mantle’s chemically distinct ‘scars’

Earth

The age of Earth’s inner core revised

-A grain-size comparator chart (to scale). The chart shows the different size fractions from silt (63 µm) through to large cobbles (128256 mm). Such charts are useful for field comparisons.

Grain Size : What is Grain Size? How is Grain Size...

Ol Doinyo Lengai volcano in Tanzania, a source of carbonate-rich magma.

Geologists publish new findings on carbonate melts in Earth’s mantle

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

1...456...33Page 5 of 33

Related Articles

All
Facebook Instagram Linkedin TikTok Twitter Youtube
© 2011-2025. All Rights Reserved.