A study published in the Journal of Quaternary Science reports a key archaeological site on the island of Jersey has preserved geological deposits thought to have been removed by excavation a century ago.
A large portion of the site, the La Cotte de St. Brelade cave on the island's southeastern coastline, contains sediments dating to the last Ice Age, preserving 250,000 years of climate change and archaeological evidence, the researchers said.
The site contains the only known late Neanderthal remains from northwestern Europe, they said.
"In terms of the volume of sediment, archaeological richness and depth of time, there is nothing else like it known in the British Isles," archaeologist Matt Pope of University College London said.
"Given that we thought these deposits had been removed entirely by previous researchers, finding that so much still remains is as exciting as discovering a new site."
Parts of the sequence of sediments at the site date between 100,000 years and 47,000 years old, researchers said.
"We were sure from the outset that the deposits held some archaeological potential, but these dates indicate we have uncovered something exceptional," Pope said. "We have a sequence of deposits which span the last 120,000 years still preserved at the site. Crucially, this covers the period in which Neanderthal populations apparently went 'extinct.'"
It was during this period Neanderthals appear to have been replaced by Homo sapiens, the researchers said.