The Roxby Formation, previously known as the Permian Upper Marls, is a
formation
Formation may refer to:
Linguistics
* Back-formation, the process of creating a new lexeme by removing or affixes
* Word formation, the creation of a new word by adding affixes
Mathematics and science
* Cave formation or speleothem, a secondary ...
from the
Guadalupian
The Guadalupian is the second and middle Series (stratigraphy), series/Epoch (geology), epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico an ...
-
Early Triassic
The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 251.9 Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which ...
of eastern England (formation dies out at
Nottinghamshire
Nottinghamshire (; abbreviated ''Notts.'') is a ceremonial county in the East Midlands of England. The county is bordered by South Yorkshire to the north-west, Lincolnshire to the east, Leicestershire to the south, and Derbyshire to the west. Th ...
).
The formation is made up largely of mudstone and siltstone, reddish brown, with subordinate sandstone.
[BSmith, D B, Harwood, G M, Pattison, J and Pettigrew, T H. 1986: ''A revised nomenclature for Upper Permian strata in eastern England''. 9-17 in Harwood, G M and Smith, D B (editors): ''The English Zechstein and Related Topics''. Geological Society Special Publication No.22.]
References
Geologic formations of England
{{UK-geologic-formation-stub