New glacier discovery sheds light on Earth's origins
The Neoproterozoic Era
The period between one billion and 543 million years ago is known as the Neoproterozoic Era. During this time, Earth existed in a deep freeze.
New research
According to a new study, however, the flow of ancient glaciers may have been crucial in laying the groundwork for the evolution of complex organisms.
How it works
The process of glaciation is known to scrape up nutrients from the Earth’s crust and dump them into oceans, rivers, and lakes.
Key uncertainties
Until recently, however, this theory had little merit because scientists were not sure how the glaciers during the Neoproterozoic Era moved.
The new study
However, according to a new study conducted by researchers at Curtin University in Perth, Australia, the glaciers did in fact move on Snowball Earth.
Zircons
In particular, they looked at zircons, which are exceptionally durable crystalized minerals that can weather extreme geological events.
Findings
They found that the composition of the early sediments differed dramatically from the composition of the later sediments.
Interpretation
According to the study’s authors, this suggests that the rocks were exposed and were eroded over time by the movement of glaciers.
Fewer minerals
The rocks from the time of Hothouse Earth, by contrast, featured a narrower range of minerals. This suggests they were not disturbed by moving glaciers.
The estimated timeline
According to the study’s authors, these results serve as evidence that there were at least two major glaciation events between 720 and 635 million years ago.
Remaining questions
Indeed, experts have questioned whether the minerals poured into the oceans during these glaciation events would have been enough to trigger long-term environmental changes.
Ongoing debate
The findings from this study are therefore being treated as interesting evidence in an ongoing debate, rather than as the final answer.
Everything is connected
If they prove nothing else, the results from this study at least serve as a reminder of how changing one part of our planet affects other parts of it.
Changes on modern Earth
Compared with this, the changes taking place today because of human-induced climate change are doing so at a dizzying speed.
