Remote Scottish islands may hold the key to understanding a pivotal period in Earth's history, when the planet froze over some 720 million years ago. The Garvellach islands, off the west coast of Scotland, have remained largely undisturbed by humans, preserving rock layers that scientists believe contain a unique record of the 'Snowball Earth' event.
Researchers from University College London (UCL) have identified that the cliff-edge rocks on the islands date back to the critical period just before the great freeze. Until now, no rocks on Earth had been found from this time, as most were eroded away by glaciers. The findings, published in the Journal of the Geological Society of London, could help solve the mystery of what triggered the global ice age.
Professor Graham Shields, who led the research, told BBC News: 'We capture that moment of entering an ice age in Scotland that is missing in all other localities in the world. Millions of critical years are missing in other places because of glacial erosion – but it is all there in the layers of rock in the Garvellachs.'
Bizarrely, Scotland was located on the equator 720 million years ago, making the discovery even more significant. The breakthrough was made by PhD student Elias Rugen, who identified the rock layers as coming from the period that does not exist anywhere else on Earth.
The discovery has garnered international attention, with the possibility of a 'golden spike' being awarded to the site. The golden spike is a marker placed at locations that best represent a geological event. Elias is pressing his case and has invited judges to examine the site. A decision is pending, but if successful, a remote Scottish island could become a global reference point for this ancient climatic shift.
