Ancient mountains recorded in Antarctic sandstones reveal potential links to global events

August 04, 2020

A new analysis of sandstones from Antarctica indicates there may be important links between the generation of mountain belts and major transitions in Earth's atmosphere and oceans.

A team of researchers analyzed the chemistry of tiny zircon grains commonly found in the Earth's continental rock record to determine their ages and chemical compositions. The team included scientists from the University of Wisconsin Oshkosh, Michigan Technological University and ETH Zurich in Switzerland.

The study was published recently in the international peer-reviewed journal Terra Nova, which features short innovative papers about the solid Earth and planetary sciences.

"Mountain building occurs in association with the plate tectonic motions of the continents," said Paulsen, the lead author on the paper. "Geologists have long recognized that the generation of significant mountainous relief has the potential to profoundly influence the chemistry of the Earth's oceans and atmosphere."

Yet there are significant questions about the patterns of mountain building in Earth's past, especially associated with the ancient rock record leading up to the explosion of life about 541 million years ago.

"Mountains tend to be worn down by water and wind that ultimately transports their sedimentary remains to the oceans, leaving an incomplete puzzle for geologists to fit together," said Deering, a coauthor on the paper. "However, there is increasing evidence that missing pieces of the puzzle are found in the sands of ancient beaches and rivers, which are essentially the remnants of mountains produced by weathering and erosion."

The researchers' findings, based on an analysis of a large sample of zircon grains from sandstone recovered in Antarctica, may signify key links in the evolution of the Earth's rock cycle and its atmosphere and oceans.

"We found two primary periods of increased average crustal thickness associated with volcanic chains along convergent plate boundaries, implying an increased proportion of higher mountains at these times," Paulsen said.

"Both episodes occurred during major reorganization of the continents when they separated and drifted on the Earth's surface over time. They also overlap with snowball Earth glaciations--when the whole Earth was frozen over--and associated steps in oxygenation of the atmosphere, which may have been critical for the evolution of life. These correlations suggest an important causal link between plate tectonics and major transitions in Earth's atmosphere and oceans."
-end-


University of Wisconsin Oshkosh

Related Antarctica Articles from Brightsurf:

Ice loss likely to continue in Antarctica
A new international study led by Monash University climate scientists has revealed that ice loss in Antarctica persisted for many centuries after it was initiated and is expected to continue.

Antarctica: cracks in the ice
In recent years, the Pine Island Glacier and the Thwaites Glacier on West-Antarctica have been undergoing rapid changes, with potentially major consequences for rising sea levels.

Equatorial winds ripple down to Antarctica
A CIRES-led team has uncovered a critical connection between winds at Earth's equator and atmospheric waves 6,000 miles away at the South Pole.

Antarctica more widely impacted by humans than previously thought
Using a data set of 2.7 million human activity records, the team showed just how extensive human use of Antarctica has been over the last 200 years

Antarctica more widely impacted than previously thought
Researchers at Australia's Monash University, using a data set of 2.7 million human activity records, have shown just how extensive human use of Antarctica has been over the last 200 years.

Predicting non-native invasions in Antarctica
A new study identifies the non-native species most likely to invade the Antarctic Peninsula region over the next decade.

Persistent drizzle at sub-zero temps in Antarctica
When the temperature drops below freezing, snow and ice are expected to follow.

Human 'footprint' on Antarctica measured for first time
The full extent of the human 'footprint' on Antarctica has been revealed for the first time by new IMAS-led research which used satellite images to measure stations, huts, runways, waste sites and tourist camps at 158 locations.

Iguana-sized dinosaur cousin discovered in Antarctica
Scientists have discovered the fossils of an iguana-sized reptile, which they named 'Antarctic king,' that lived at the South Pole 250 million years ago (it used to be warmer).

Scientists drill to record depths in West Antarctica
A team of scientists and engineers has for the first time successfully drilled over two kilometres through the ice sheet in West Antarctica using hot water.

Read More: Antarctica News and Antarctica Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.