Geologists discover that the Earth was covered by gigantic glaciers

Madrid. Geologists discovered strong evidence in Colorado that hundreds of millions of years ago the Earth was covered by gigantic glaciers that transformed it into an icicle in space.

The study, led by the University of Colorado at Boulder, is a big success for proponents of an old theory known as Snowball Earth. It postulates that, between about 720 and 635 million years ago, and for reasons that are still unclear, an uncontrolled chain of events radically altered the planet’s climate. Temperatures plummeted and sheets of ice that may have been several kilometers thick spread across every centimeter of the Earth’s surface.

This study presents the first physical evidence that the Snowball Earth reached the heart of the continents at the equatorLiam Courtney-Davies, lead author of the new study and a researcher at the University of Colorado at Boulder, said in a statement.

The study focuses on the Front Range mountain range of the Colorado Rocky Mountains. Here, a series of rocks dubbed the Tavakaiv or Tava sandstones contain clues to this frigid period in Earth’s past, Courtney-Davies said.

The researchers used a dating technique called laser ablation mass spectrometry, which attacks minerals with unusual light sources to release some of the atoms inside. They showed that these rocks had been forced underground between 690 and 660 million years ago, most likely due to the weight of enormous glaciers pressing down on them.

Courtney-Davies added that the study will help scientists understand a critical phase not only in the planet’s geological history, but also in the history of life on Earth. The first multicellular organisms may have emerged in the oceans immediately after Snowball Earth thawed.

The climate evolved and life with it. All of these things happened during the Snowball Earth upheaval.he highlighted. We have to better characterize this entire period to understand how we and the planet evolved together..

The term Snowball Earth dates back to an article published in 1992 by American geologist Joseph Kirschvink.

However, despite decades of research, scientists still cannot agree on whether the entire globe really froze. Geologists, for example, have discovered traces of thick ice from this time period along ancient coastal areas, but not in the interior of continents near the equator.

That’s where Colorado comes into the picture. At that time, the region was not at the northern latitudes where it is today. Instead, the area rested on the equator as a landlocked part of the ancient supercontinent Laurentia.

If glaciers formed here, scientists believe, then they could have formed anywhere.

The search for that missing piece of the puzzle led Courtney-Davies and his colleagues to the Tava sandstones. Today, these formations protrude from the ground in some places along Colorado’s Front Range mountain range, most notably around Pikes Peak. To the untrained eye, they may appear to be ordinary-looking yellow to brown rocks that extend in vertical bands from less than an inch to many feet wide.

But for geologists, these formations have an unusual history. They likely began as sands on the surface of Colorado at some point in the past. But then the forces pushed them underground, like claws digging into the earth’s crust.

These are classic geological features called injectites that often form beneath some ice sheets, including in modern-day Antarctica.Courtney-Davies said.

He wanted to find out if the Tava sandstones were also connected to ice sheets. To do so, the researchers calculated the ages of the mineral veins that ran through those features. It was a Eureka moment: the group’s findings suggest that the Tava sandstone had been pushed underground during the Snowball Earth. The group suspects that, at that time, thick sheets of ice formed over Colorado, exposing the sands to intense pressures. Finally, and with nowhere else to go, they pushed down to the bedrock below.

We are excited to have had the opportunity to unravel the history of the only Snowball Earth deposits that have been identified so far in Colorado.Flowers declared.

Researchers are still undecided whether such features formed in Colorado during Snowball Earth, they probably formed elsewhere in North America as well.

We want to spread the word so that others can try to find these features and help us build a more complete picture of Snowball Earth.Courtney-Davies highlighted.