The Whitchurch Sand Formation is a
geological formation, in
England. part of the
Wealden Group
The Wealden Group, occasionally also referred to as the Wealden Supergroup, is a group (a sequence of rock strata) in the lithostratigraphy of southern England. The Wealden group consists of paralic to continental (freshwater) facies sedimentary ...
, it is preserved as an
inlier
An inlier is an area of older rock (geology), rocks surrounded by younger rocks. Inliers are typically formed by the erosion of overlying younger rocks to reveal a limited outcrop, exposure of the older underlying rocks. Fault (geology), Faulting o ...
in hills in
Buckinghamshire
Buckinghamshire (), abbreviated Bucks, is a ceremonial county in South East England that borders Greater London to the south-east, Berkshire to the south, Oxfordshire to the west, Northamptonshire to the north, Bedfordshire to the north-ea ...
,
Oxfordshire
Oxfordshire is a ceremonial and non-metropolitan county in the north west of South East England. It is a mainly rural county, with its largest settlement being the city of Oxford. The county is a centre of research and development, primarily ...
and
Wiltshire. It was deposited in the
Valanginian stage of the
Early Cretaceous
The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma.
Geology
Pro ...
. The lithology largely consists of unconsolidated fine-medium grained sand with isolated bodies of
limonite
Limonite () is an iron ore consisting of a mixture of hydrated iron(III) oxide-hydroxides in varying composition. The generic formula is frequently written as FeO(OH)·H2O, although this is not entirely accurate as the ratio of oxide to hydroxid ...
cemented sandstone, with localised beds of siltstone and mudstone.
References
Cretaceous England
Geologic formations of England
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