**New Evidence Suggests Tropical Regions Were Once Blanketed by Huge Ice Sheets**

Surprisingly, even the hottest tropical areas of the Earth might have been encased in colossal ice sheets in the past. Approximately 720 to 635 million years ago, long before dinosaurs inhabited the Earth, our planet went through a dramatic ice age. This epoch, referred to as “Snowball Earth,” was marked by intense glaciations, although the notion of the entire planet freezing remains a topic of debate. Recent findings from Colorado—once situated near the equator—indicate that even the warmest locales of Earth were enveloped by glaciers.

“This research puts forth the first tangible evidence that Snowball Earth encroached upon the central parts of continents at the equator,” stated Liam Courtney-Davies, a geologist at CU Boulder and the primary author of the study. The results were published lately in the *Proceedings of the National Academy of Sciences*, a highly regarded scientific publication.

### SEE ALSO: [The initial images of Earth are chilling](https://mashable.com/article/earth-first-images-space-history)

A significant drop in greenhouse gases, especially carbon dioxide, might have instigated the planet’s plunge into a frozen condition. Previous research indicated that while the overall temperature of Earth fell drastically below freezing, certain regions of the ocean and land might have avoided becoming ice-bound. Nonetheless, the fresh evidence gathered from the Colorado mountains suggests noteworthy glaciation in tropical zones as well.

The crucial evidence is derived from Tava sandstone, a rock type located in the Rocky Mountains. Sandstone is formed from compacted sand, typically deposited by rivers and concealed beneath layers of silt. In this instance, the Tava sandstone displays characteristics akin to those found beneath contemporary ice sheets, such as those in Antarctica.

To ascertain whether glaciers contributed to the compaction of this sandstone, researchers examined mineral veins within the rock. Employing lasers, they gauged the content of uranium in these ancient minerals. Given that uranium decays at a consistent rate, it serves as a dependable method for dating geological structures. The findings revealed that the sandstone dates back to the Snowball Earth period, hundreds of millions of years in the past.

### SEE ALSO: [Where to observe retreating glaciers](https://mashable.com/article/where-to-see-retreating-glaciers)

This revelation offers strong evidence that vast glaciers once enveloped tropical Colorado. However, this represents only a singular site, and additional research is necessary to comprehend the full scope of the ice coverage during the Snowball Earth era.

“We aim to raise awareness so that others can seek these features and assist us in painting a more comprehensive image of Snowball Earth,” remarked Courtney-Davies.

Ultimately, this severe ice age came to a close, potentially due to a massive asteroid strike that released heat-trapping gases into the atmosphere, leading to the melting of ice and the withdrawal of glaciers. The Earth’s crust continues to unveil the dynamic history of our planet over billions of years—a narrative that is still in progress on our constantly evolving Earth.

### SEE ALSO: [Earth’s forthcoming supercontinent](https://mashable.com/article/earth-future-supercontinent)