| Computer Code: |
BYD |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Holocene Epoch (QH)
— Holocene Epoch (QH) |
| Lithological Description: |
The Barroway Drove Beds comprise soft grey clays and silty clays which were deposited in salt marshes and shallow water brackish lagoons cut by a complex network of tidal channels and creeks, subsequently infilled with silts and fine grained sands. Rhizomes of the salt-tolerant reed Phragmites occur throughout the clays and thin mats of rotted, drifted stems of reeds and sedges are common at many levels. At outcrop the silts and fine-grained sands that infill the creeks form low sinuous ridges or 'roddons'. |
| Definition of Lower Boundary: |
The Barroway Drove Beds rest with unconformity commonly on the Fen Lower Peat but also on the intertidal sands. They also rest unconformably on glaciofluvial sand and gravel and on bedrock. |
| Definition of Upper Boundary: |
The Barroway Drove Beds are generally overlain by the Nordelph Peat Member or the Terrington Beds. Where the Nordelph Peat is present the upper boundary is obvious, but where the peat is absent and the lithology very similar to the overlying Terrington Beds then the upper boundary is difficult to distinguish. The presence of rootlet remains is characteristic of theTerrington Beds and so may help identify the upper boundary of the Barroway Drove Beds. |
| Thickness: |
Up to about 12 m. |
| Geographical Limits: |
Fenland area of East Anglia. |
| Parent Unit: |
Fenland Formation (FEND)
|
| Previous Name(s): |
Fen Clay (Godwin, 1940); Butery Clay (Skertchly, 1877) [Obsolete Name and Code: Use BYD]
(-1408)
|
| Alternative Name(s): |
Tidal flat deposits
|
| Stratotypes: |
| Type Area |
Area around the hamlet of Barroway Drove to the west of Downham Market. Gallois, 1979. |
| Reference(s): |
| Horton, A. 1989. Geology of the Peterborough district. Memoir of the British Geological Survey, Sheet 158 (England & Wales). |
| Whitaker, W and Jukes-Browne, A J. 1899. The geology of the borders around The Wash: including Boston and Hunstanton. Memoir of the Geological Survey of England and Wales. |
| Gallois, R W, 1994. The geology of the country around King's Lynn and The Wash. Memoir of the British Geological Survey, Sheet 145 and part of 129 (England and Wales). |
| Gallois, R W. 1988. Geology of the country around Ely. Memoir of the British Geological Survey, Sheet 173 (England and Wales). |
| Skertchly, S B J. 1877. The geology of Fenland. Memoir of the Gological Survey of Great Britain. |
| Gallois, R W. 1979. Geological investigations for the Wash Water Storage Scheme. Report of the Institute of Geological Sciences, 78/19, 1-74pp. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E129
E128
E144
E145
E158
E159
E172
E173
E127
E116
|
