Upper Greensand Formation

The Upper Greensand Formation is a Cretaceousformation of Albian to Cenomanian in age, found within the Wessex Basin and parts of the Weald Basin in southern England.^[1] It overlies the Gault Clay and underlies the Chalk Group. It varies in thickness from zero to 75 m. It is predominantly a glauconitic fine-grained sandstone, locally becoming silty. Fragmentary dinosaur remains, such as those assigned to Iuticosaurus, have been recovered from this formation. It has been quarried as a building stone from Roman times, and used in London and the area of its outcrop from Devon to East Sussex.

Sandstones from the Upper Greensand have been used as building stone since at least Roman times.^[2]Reigate Stone was mined from the Upper Greensand in north east Surrey throughout the Middle Ages and early modern period,^[3] forming the most important source of freestone in Medieval London.^[2] In Dorset, the Shaftesbury Sandstone was quarried between Shaftesbury and Okeford Fitzpaine and used in the Shaftesbury area and along the Stour valley. In southeastern Devon, the Bindon Sandstone was quarried near Branscombe and used in buildings such as Exeter Cathedral.^[4] Other building stones quarried from the Upper Greensand in the county include Salcombe Stone from near the border with Somerset, and the Green Glauconitic Sandstone from the western side of the Blackdown Hills.^[5]

La piedra de Hurdcott se extraía en Wiltshire y se utilizaba especialmente en Mere y Shaftesbury. Actualmente se produce en una cantera en Barford St Martin . La piedra de Potterne se extrae cerca de Potterne y se utiliza allí y en el Valle de Pewsey . ^{[ 6 ]} En la Isla de Wight, la arenisca verde superior se ha extraído desde la época romana, incluyendo la piedra de Ventnor cerca de Ventnor , con variedades de piedra verde de Ventnor y piedra de zorro de Ventnor, y la piedra de Bonchurch que solo se encuentra en Bonchurch . El sílex de la parte superior de la formación también se ha utilizado como piedra de construcción desde el siglo XVII. ^{[ 7 ]} En West Sussex y Hampshire , la piedra de Malmstone se extraía y se utilizaba en edificios como el Castillo de Winchester ^{[ 8 ]} y el Castillo de Amberley . ^{[ 9 ]} En East Sussex , la arenisca de Eastbourne se extraía de la costa en Eastbourne y se utilizaba en edificios de la ciudad, como la iglesia de Santa María la Virgen. ^{[ 10 ]}