ABSTRACT
A large block of bedrock detached from the substrate beneath a glacier, occurring within or adjacent to associated glacigenic or other sediments (Figure R.1). A raft may be transported by ice for a considerable distance (tens or hundreds of kilometres) and is emplaced by glaciotectonic processes, yet retains its original lithological appearance. Large raft of locally derived Cretaceous chalk at Overstrand, Norfolk, England. It has been raised several metres above the host bedrock and emplaced by glaciotectonic processes, along with sand and gravel. The base of the raft is defined by a thrust. The deposit was emplaced during the Middle Pleistocene Anglian glaciation. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315373157/95d5ad9e-a71d-4f11-a609-2c025b95638b/content/figr_1.jpg"/> (Photograph by Emrys Phillips.)
