Did Earth As soon as Freeze Fully? New Proof Present in Colorado Rocks

New analysis on distinctive sandstone formations within the Colorado Rocky Mountains could verify that Earth skilled a large, 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 adolescence not solely survived however later advanced into advanced multicellular organisms.

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

Tava sandstone formation linked to historic ice pressures

Pikes Peak, a sacred web site recognized to the Ute folks 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 examine’s lead authors, Christine Siddoway and Rebecca Flowers, used superior radiometric relationship 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 relationship to verify the Tava sandstone’s origins throughout the Snowball Earth timeframe. The crew means that the ice sheets protecting the equatorial Laurentia landmass, now a part of North America, created the pressures essential to kind 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 giant parts of Earth’s rock file. The findings at Pikes Peak point out that comparable unconformities could predate Snowball Earth, suggesting advanced erosion processes over thousands and thousands 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.