Press item re bluestones and glaciation

New insight into Preseli bluestones at Stonehenge
Western Telegraph, Saturday 5th March 2011
http://www.westerntelegraph.co.uk/news/8890478.Researchers_step_closer_to_solving_stone_mystery/

The age-old question of how Preseli bluestones ended up at Stonehenge is a step closer to being answered following new research.

It had been believed that Neolithic Age man transported the stone to Wiltshire from the Mynydd Preseli area via Milford Haven and the Bristol Channel on rafts, but the new findings indicate that glacial movements may have been more likely.

The source of the bluestones at the historic site have long been the subject of fascination and one type, the spotted dolerite, was traced to the county in the early 1920s.

The source of other bluestones used, such as rhyolites, remained unknown until geologists at Amgueddfa Cymru - National Museum Wales also linked it to the area using a range of laser mass spectrometry techniques analysing chemical composition and microbiology.

One of the researchers Dr Richard Bevins said: “This recent discovery is very significant as it potentially provides us with new clues for understanding how and possibly why the Welsh bluestones were transported to the Stonehenge area.

“If humans were responsible then an alternative route might need to be considered. However, some believe that the stones were transported by the actions of glacier sheets during the last glaciation and so the Pont Saeson discovery will need appraising in the context of this hypothesis.”

Dr Brian John, from Newport, author of The Bluestone Enigma which argues the case for glacial transport, said: “We now know that the erratic or bluestone material at Stonehenge, of all shapes and sizes, has come from at least 30 different sources.

“On that basis alone it is entirely logical to assume that the stones have been transported by ice for most - but not necessarily all - of their journey to Stonehenge.”