Friday, August 8, 2025
Science
No Result
View All Result
  • Login
  • HOME
  • SCIENCE NEWS
  • CONTACT US
  • HOME
  • SCIENCE NEWS
  • CONTACT US
No Result
View All Result
Scienmag
No Result
View All Result
Home Science News Technology and Engineering

Rock steady: Study reveals new mechanism to explain how continents stabilized

May 8, 2024
in Technology and Engineering
Reading Time: 4 mins read
0
cratons
66
SHARES
601
VIEWS
Share on FacebookShare on Twitter
ADVERTISEMENT
ADVERTISEMENT

UNIVERSITY PARK, Pa. — Ancient, expansive tracts of continental crust called cratons have helped keep Earth’s continents stable for billions of years, even as landmasses shift, mountains rise and oceans form. A new mechanism proposed by Penn State scientists may explain how the cratons formed some 3 billion years ago, an enduring question in the study of Earth’s history.

cratons

Credit: Jesse Reimink

UNIVERSITY PARK, Pa. — Ancient, expansive tracts of continental crust called cratons have helped keep Earth’s continents stable for billions of years, even as landmasses shift, mountains rise and oceans form. A new mechanism proposed by Penn State scientists may explain how the cratons formed some 3 billion years ago, an enduring question in the study of Earth’s history.

The scientists reported today (May 8) in the journal Nature that the continents may not have emerged from Earth’s oceans as stable landmasses, the hallmark of which is an upper crust enriched in granite. Rather, the exposure of fresh rock to wind and rain about 3 billion years ago triggered a series of geological processes that ultimately stabilized the crust — enabling the crust to survive for billions of years without being destroyed or reset.

The findings may represent a new understanding of how potentially habitable, Earth-like planets evolve, the scientists said.  

“To make a planet like Earth you need to make continental crust, and you need to stabilize that crust,” said Jesse Reimink, assistant professor of geosciences at Penn State and an author of the study. “Scientists have thought of these as the same thing — the continents became stable and then emerged above sea level. But what we are saying is that those processes are separate.”

Cratons extend more than 150 kilometers, or 93 miles, from the Earth’s surface to the upper mantle — where they act like the keel of a boat, keeping the continents floating at or near sea level across geological time, the scientists said.

Weathering may have ultimately concentrated heat-producing elements like uranium, thorium and potassium in the shallow crust, allowing the deeper crust to cool and harden. This mechanism created a thick, hard layer of rock that may have protected the bottoms of the continents from being deformed later — a characteristic feature of cratons, the scientists said.

“The recipe for making and stabilizing continental crust involves concentrating these heat-producing elements — which can be thought of as little heat engines — very close to the surface,” said Andrew Smye, associate professor of geosciences at Penn State and an author of the study. “You have to do that because each time an atom of uranium, thorium or potassium decays, it releases heat that can increase the temperature of the crust. Hot crust is unstable — it’s prone to being deformed and won’t stick around.”

As wind, rain and chemical reactions broke down rocks on the early continents, sediments and clay minerals were washed into streams and rivers and carried to the sea where they created sedimentary deposits like shales that were high in concentrations of uranium, thorium and potassium, the scientists said.

Collisions between tectonic plates buried these sedimentary rocks deep in the Earth’s crust where radiogenic heat released by the shale triggered melting of the lower crust. The melts were buoyant and ascended back to the upper crust, trapping the heat-producing elements there in rocks like granite and allowing the lower crust to cool and harden.

Cratons are believed to have formed between 3 and 2.5 billion years ago — a time when radioactive elements like uranium would have decayed at a rate about twice as fast and released twice as much heat as today.

The work highlights that the time when the cratons formed on the early middle Earth was uniquely suited for the processes that may have led them to becoming stable, Reimink said.

“We can think of this as a planetary evolution question,” Reimink said. “One of the key ingredients you need to make a planet like Earth might be the emergence of continents relatively early on in its lifespan. Because you’re going to create radioactive sediments that are very hot and that produce a really stable tract of continental crust that lives right around sea level and is a great environment for propagating life.”

The researchers analyzed uranium, thorium and potassium concentrations from hundreds of samples of rocks from the Archean period, when the cratons formed, to assess the radiogenic heat productivity based on actual rock compositions. They used these values to create thermal models of craton formation.

“Previously people have looked at and considered the effects of changing radiogenic heat production through time,” Smye said. “But our study links rock-based heat production to the emergence of continents, the generation of sediments and the differentiation of continental crust.”

Typically found in the interior of continents, cratons contain some of the oldest rocks on Earth, but remain challenging to study. In tectonically active areas, mountain belt formation might bring rocks that had once been buried deep underground to the surface.

But the origins of the cratons remain deep underground and are inaccessible. The scientists said future work will involve sampling ancient interiors of cratons and, perhaps, drilling core samples to test their model.

“These metamorphosed sedimentary rocks that have melted and produced granites that concentrate uranium and thorium are like black box flight recorders that record pressure and temperature,” Smye said. “And if we can unlock that archive, we can test our model’s predictions for the flight path of the continental crust.”

Penn State and the U.S. National Science Foundation provided funding for this work.



Journal

Nature

DOI

10.1038/s41586-024-07307-1

Method of Research

Computational simulation/modeling

Subject of Research

Not applicable

Article Title

Subaerial weathering drove stabilization of continents

Article Publication Date

8-May-2024

Share26Tweet17
Previous Post

Vertical atmospheric measurements and simulations demonstrate important contribution of combustion-related ammonium during haze pollution in Beijing

Next Post

Childhood maltreatment responsible for up to 40 percent of mental health conditions

Related Posts

blank
Technology and Engineering

Eco-Friendly ZIF-7 Carbon for Sensitive Rhodamine B Detection

August 8, 2025
blank
Technology and Engineering

Weathered Microplastics in Blood Affect Clotting

August 7, 2025
blank
Technology and Engineering

Copper-Oxide Flakes: A Breakthrough in Supercapacitor Electrode Performance

August 7, 2025
blank
Technology and Engineering

UVA Leverages AI Technology to Enhance Brain Cancer Treatment

August 7, 2025
blank
Technology and Engineering

Smart Deep Learning for Li-Ion Battery Health Prediction

August 7, 2025
blank
Technology and Engineering

Bystander T Cells Boost the Antitumor Efficacy of Bispecific Antibodies

August 7, 2025
Next Post
Childhood maltreatment responsible for up to 40 percent of mental health conditions

Childhood maltreatment responsible for up to 40 percent of mental health conditions

  • Mothers who receive childcare support from maternal grandparents show more parental warmth, finds NTU Singapore study

    Mothers who receive childcare support from maternal grandparents show more parental warmth, finds NTU Singapore study

    27531 shares
    Share 11009 Tweet 6881
  • University of Seville Breaks 120-Year-Old Mystery, Revises a Key Einstein Concept

    942 shares
    Share 377 Tweet 236
  • Bee body mass, pathogens and local climate influence heat tolerance

    641 shares
    Share 256 Tweet 160
  • Researchers record first-ever images and data of a shark experiencing a boat strike

    506 shares
    Share 202 Tweet 127
  • Warm seawater speeding up melting of ‘Doomsday Glacier,’ scientists warn

    310 shares
    Share 124 Tweet 78
Science

Embark on a thrilling journey of discovery with Scienmag.com—your ultimate source for cutting-edge breakthroughs. Immerse yourself in a world where curiosity knows no limits and tomorrow’s possibilities become today’s reality!

RECENT NEWS

  • New Phase II Trial Targets Advanced Follicular Lymphoma
  • Eco-Friendly ZIF-7 Carbon for Sensitive Rhodamine B Detection
  • Deep Learning Model Enhances Detecting Brain Hemorrhage
  • Magnetosome-Bearing Bacteria Thrive in Oxygen-Stratified Freshwaters

Categories

  • Agriculture
  • Anthropology
  • Archaeology
  • Athmospheric
  • Biology
  • Bussines
  • Cancer
  • Chemistry
  • Climate
  • Earth Science
  • Marine
  • Mathematics
  • Medicine
  • Pediatry
  • Policy
  • Psychology & Psychiatry
  • Science Education
  • Social Science
  • Space
  • Technology and Engineering

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 4,858 other subscribers

© 2025 Scienmag - Science Magazine

Welcome Back!

Login to your account below

Forgotten Password?

Retrieve your password

Please enter your username or email address to reset your password.

Log In
No Result
View All Result
  • HOME
  • SCIENCE NEWS
  • CONTACT US

© 2025 Scienmag - Science Magazine

Discover more from Science

Subscribe now to keep reading and get access to the full archive.

Continue reading