| Computer Code: |
PRSG |
Preferred Map Code: |
notEntered |
| Status Code: |
Pending Upgrade |
| Age range: |
Pleistocene Epoch (QP)
— Pleistocene Epoch (QP) |
| Lithological Description: |
A terrace deposit of the Sudbury Formation (SBRY) in the Valley of the Upper Thames upstream of Oxford. A largely decalcified chalk-flint gravel which in-fills the Princes Risborough Gap [SP 805 000] in the Chilterns escarpment on the margins of the Thame basin. Similar deposits occur in analogous 'wind gaps' elsewhere, e.g. near Wendover and Tring (Sherlock, 1922). The unit probably relates to the Beaconsfield Gravel (BDGR) or Gerrards Cross Gravel (GCGR) members (Sumbler, 1995; Horton et al., 1995). |
| Definition of Lower Boundary: |
none recorded or not applicable
|
| Definition of Upper Boundary: |
none recorded or not applicable
|
| Thickness: |
none recorded or not applicable
|
| Geographical Limits: |
The Princes Risborough Gap in the Chilterns escarpment. |
| Parent Unit: |
Sudbury Formation (SBRY)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
The Princes Risborough Gap [SP 805 000] in the Chilterns escarpment. |
| Reference(s): |
| McMillan, A A, Hamblin, R J O, and Merritt, J W. 2011. A lithostratigraphical framework for onshore Quaternary and Neogene (Tertiary) superficial deposits of Great Britain and the Isle of Man. British Geological Survey Research Report, RR/10/03. 343pp. |
| Horton, A, Sumbler, M G, Cox, B M and Ambrose, K, 1995. Geology of the country around Thame. Memoir of the British Geological Survey, Sheet 237 (England and Wales). |
| Sumbler, M G. 1995. The terraces of the rivers Thame and Thames and their bearing on the chronology of glaciation in central and eastern England. Proceeding of the Geologists' Association, Vol.106, 93-106. |
| Sherlock, R L. 1922. The geology of the country around Aylesbury and Hemel Hempstead. Memoir of the Geological Survey of Great Britain, Sheet 238. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E237
|
