Recent research by Curtin University reveals that an ancient influence, previously believed to have occurred 1.2 billion years ago, actually took place 990 million years ago, leading to the formation of the STAC FADA member. This discovery corrects the dating of some of the UK’s oldest non-marine microfossils and their significance in the timeline of eukaryotic colonization on land.
STAC FADA member. Image credit: Tony Prave.
“We utilized small zircon crystals as geological ‘time capsules’ to accurately date the impact at 990 million years ago,” stated Professor Chris Kirkland from Curtin University.
“These tiny crystals recorded precise moments of impact, some transforming into the rare mineral Reidite, which forms under extreme pressure.”
“This provided irrefutable evidence that the meteorite strike initiated the STAC FADA deposit.”
“When a meteorite strikes, it partially resets the atomic clocks within the zircon crystal. Although these ‘broken clocks’ can’t generate dates, they developed a model to reconstruct timing, affirming the impact’s occurrence 990 million years ago.”
The impact events coincided with the earliest emergence of freshwater eukaryotes, the ancient precursors to plants, animals, and fungi.
“The new date indicates that these life forms in Scotland appeared roughly at the same time as the meteorite impact,” Professor Kirkland remarked.
“This presents intriguing questions about whether significant impacts could have affected environmental conditions, potentially influencing early ecosystems.”
“The impact crater has yet to be located, but this study has gathered additional clues that may eventually uncover its position.
“Understanding the timeline of meteorite impacts will enable us to explore their potential effects on Earth’s environment and the diversification of life beyond the oceans.”
The team’s findings will be published in the journal Geological.
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CL Kirkland et al. The impact of Scottish meteors 100 million years ago. Geological Published online on April 28, 2025. doi: 10.1130/g53121.1
Source: www.sci.news
