Bunter beds are
sandstone deposits containing rounded pebbles. They can be found in
Warwickshire,
Cheshire,
Staffordshire,
Nottinghamshire,
Yorkshire,
Devon and
Dorset in
England. They are thought to be alluvial deposits and, judging from the rounding of the mainly
quartzite pebbles, to have resulted from prolonged transportation in a large and turbulent river, resulting in powerful abrasion. The deposits in the
English Midlands are thought to have been transported in this way northwards from
Brittany,
France. This supposed river has been called the "Budleighensis", after the Devon village of
Budleigh Salterton, a site where such deposits were discovered. The depositions took place in the lower
Triassic period. Some newer conglomerates, e.g. near
Ryton in Warwickshire, are thought to have arisen during the
Ice Age by reworking and southward transportation of older deposits by ice flows.