| Computer Code: |
CBUR |
Preferred Map Code: |
notEntered |
| Status Code: |
Pending Upgrade |
| Age range: |
Ludlow Epoch (SU)
— Early Devonian Epoch (DL) |
| Lithological Description: |
A coarse-grained sandstone with a pinstripe lamination, a sheet-like erosively-based fine- and medium-grained sandstone with red, white and green siltstones and mudstones. |
| Definition of Lower Boundary: |
Not seen due to lack of exposure. The lower boundary occurs south of Chapelton Farm at approximately NS 2240 0434, between small stream exposures of the Chapelton Burn Member to the east, and small stream exposures characteristic of the Swanshaw Sandstone Formation to the west. The lower boundary is probably conformable, as red sandstones typical of the Swanshaw Sandstone Formation are exposed a few tens of metres to the east of the Chapelton Burn Member, and also because there is not much variation in dip between the two rock types. |
| Definition of Upper Boundary: |
The upper contact is faulted in Chapelton Burn at NS 2189 0467. To the east of the fault, within the Chapeltown Burn Member, the rock types are reddish-green mudstones and fine- to medium-grained sandstones. The fault plane is marked by a 1m-wide brecciated zone. To the west of the fault are flaggy red sandstones with cross-bedding, typical of the Swanshaw Sandstone Formation in this area. |
| Thickness: |
At least 145m thick, as estimated from the partial type section. |
| Geographical Limits: |
The main outcrop is in Chapelton Burn, between Littleton and Glenhead farms, where the strata dip westwards. Extensions to the north and south cannot be defined, therefore it has been mapped as a discontinous lens of floodplain facies, surrounded by the more typical channel facies of the Swanshaw Sandstone Formation. The main Chapeltown Burn exposure is tentatively extended eastwards to the south of Chapelton Farm [NS 2240 0434], where similar rock types were observed during preliminary reconnaissance mapping (see BGS 2001, NS20NW, NS20SW and NS20NE 1: 10 000 maps). Another outcrop in the upper part of Chapelton Burn [NS2537 0557-2556 0564] was clearly identified by Jones (2001). This outcrop has been mapped as a small lens, because very small exposures between this and the main exposure show red sandstones and conglomerates typical of the Swanshaw Sandstone Formation. This exposure may be joined with the main Chapelton Burn exposure. |
| Parent Unit: |
Swanshaw Sandstone Formation (SWAS)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Partial Type Section |
The gorge section of Chapelton Burn, between 450 m north-east of Littleton Farm and 115 m south-west of Glenhead Farm, about 1.75 km south-east of Turnberry. Jones, 2001; Monaghan, 2001 |
| Reference(s): |
| Jones, N S. 2001. Sedimentology of the Swanshaw Sandstone Formation in Ayrshire. British Geological Survey Internal Report IR/01/164. |
| Monaghan, A. 2001. Geology of the Culzean to Dipple area. BGS Internal Report IR/01/165. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
S014
|
