Southcote, Berkshire of chalk, with geological surveys also finding flint samples. A map produced by the Geological Survey of Great Britain in 1860 identifies the area as being predominantly Plastic Clay (now known as the Lambeth Group) and chalk north of the river, with flint and gravel samples typical of the Bagshot Formation south of the Kennet. More specifically, the 2000 survey showed different types of gravel, including Winter Hill (variably clayey and sandy), Lynch Hill (sand and gravel with lenses of silt, clay or peat), and head (a polymict deposit usually formed by periglacial solifluction or gelifluction). The survey also identified
Granular convection similar density, such as muesli mix. Under experimental conditions, granular convection of variously sized particles has been observed forming convection cells similar to fluid motion. The convection of granular flows is becoming a well-understood phenomenon. It may be counterintuitive to find that the largest and (presumably) heaviest particles rise to the top, but several explanations are possible: The phenomenon is related to Parrondo's paradox in as much as the Brazil nuts move to the top of the mixed nuts against the gravitational gradient when subjected to random shaking. Granular convection has been probed by the use of MRI where convection