A bluestone boulder at Stonehenge: implications for the glacial transport theory

Abstract

There has been considerable dispute over the mode of transport of the Stonehenge bluestones from their multiple sources in West Wales. For a century most archaeologists have accepted that the stones were transported by humans, but a number of earth scientists have taken the view that they were entrained and transported to Salisbury Plain by glacier ice. There is remarkably little evidence in support of either theory, and for this reason any new description of a possible glacial clast found at or near the stone monument is of potentially great importance. A small bullet-shaped boulder of welded tuff was found in a Stonehenge excavation in 1924, and apart from a brief examination by geologists from the Institute of Geological Sciences (IGS) around 1970, it has been stored out of sight and out of mind. Its geological source is uncertain. Following a detailed examination of its shape and surface characteristics it is now proposed that it has been subjected to glacial transport and that it has had a long and complex history. It is also proposed that the abundant weathered and abraded bluestone boulders and slabs at Stonehenge were also glacially transported, along with many of the cobbles and stone fragments found in the sediments of the local landscape. The elaborate archaeological narrative of bluestone quarrying and human transport to Stonehenge must now be re-examined.