Moss Gives Away the Secrets of the North Seas Largest Landslide and Tsunami About 8,000 years ago one of the world’s largest mass wasting events occurred in the chilly North Sea. A submarine landslide, known as the Storegga Slide, rattled the ocean off Norway, displacing 3300 cubic km of sediment over an area approximately the size of Scotland. It is not known what exactly triggered this slide but we do know that it generated a massive tsunami that flooded areas of northern Europe. Tsunami deposits in Norway and Scotland are found above structures from ancient civilizations, causing many to wonder what happened to the people living here. Were ancient communities severely impacted by the tsunami? Were lives lost? Homes destroyed? The answer presumably lies in the time of year the tsunami occurred. The Mesolithic (“middle Stone Age”) people living here would have spent most of their summers in the highlands hunting for reindeer and most of their winters near the coast where it was slightly warmer. A tsunami that occurred in the winter would have been much more devastating than one occurring in summer when inhabitants were safe in the mountains. To determine the season of this event, a recent study investigated one of the humblest of plants—moss. Many Storegga tsunami deposits contain a species of moss called Hylocomium splendens. This species has a unique growth pattern in which new segments branch off from growths that occurred the previous year. These specimens showed growth patterns typical of October-December maturity. Many were also still green—meaning that they were buried while alive. What does the moss tell us? That this tsunami was probably a catastrophe. The growth patterns suggest the tsunami occurred in late autumn, at a time when the Mesolithic people would have been retreating from the mountains and settling in for winter. Therefore, the Storegga tsunami was both large and unfortunately timed, undoubtedly wreaking havoc on the lives of Europe’s ancient peoples. -CM For the original paper: bit.ly/15GnBNE Photo credit: British Geological Survey bit.ly/1B6aDAC National Oceanography Centre bit.ly/15GnNfX Dear Readers, Most of our posts are not reaching your news feed due to fbs filtering system. If you wish to enjoy our posts more often, use the following for information on how to go about it: tmblr.co/Zyv2Js1VWMUJ0.
Posted on: Mon, 26 Jan 2015 12:21:00 +0000
Trending Topics
Recently Viewed Topics
© 2015