Did Earth Once Freeze Completely? New Evidence Found in Colorado Rocks

New analysis on distinctive sandstone formations within the Colorado Rocky Mountains might verify that Earth skilled an enormous, planet-wide freeze generally known as “Snowball Earth.” About 700 million years in the past, Earth’s floor was encased in ice, creating an excessive local weather the place formative years not solely survived however later developed into complicated multicellular organisms.

For many years, the Snowball Earth speculation was supported primarily by coastal sedimentary rocks and local weather fashions. Nevertheless, strong proof of ice sheets reaching the planet’s equatorial inside has remained elusive—till now. The current research, printed within the Proceedings of the Nationwide Academy of Sciences, identifies uncommon sandstone deposits known as Tava, discovered inside the granite formations of Colorado’s Pikes Peak. These sandstones doubtless shaped beneath the strain of ice sheets, supporting the Snowball Earth concept with new geological proof.

Tava sandstone formation linked to historical ice pressures

Pikes Peak, a sacred web site identified to the Ute individuals as Tavá Kaa-vi, is the supply of those Tava sandstone formations. Researchers found that the sandstones shaped when sandy, water-saturated sediment was pressured into weakened rock by the immense weight of ice sheets. The research’s lead authors, Christine Siddoway and Rebecca Flowers, used superior radiometric courting to find out that Tava sandstones developed round 690 to 660 million years in the past, aligning with the Cryogenian Interval.

Utilizing iron minerals discovered with the sandstone, Siddoway’s crew employed uranium-lead courting to substantiate the Tava sandstone’s origins inside the Snowball Earth timeframe. The crew means that the ice sheets masking the equatorial Laurentia landmass, now a part of North America, created the pressures essential to type these sandstone injectites.

Implications for understanding Earth’s climatic previous

This discovery strengthens the Snowball Earth speculation whereas additionally shedding gentle on different geological phenomena, together with “unconformities” the place erosion has eliminated massive parts of Earth’s rock file. The findings at Pikes Peak point out that comparable unconformities might predate Snowball Earth, suggesting complicated erosion processes over tens of millions of years. Scientists hope these insights will result in a deeper understanding of Earth’s local weather historical past and the processes that formed our liveable planet.