| Computer Code: |
CLSG |
Preferred Map Code: |
CLSG |
| Status Code: |
Full |
| Age range: |
Chadian Substage (CI)
— Chadian Substage (CI) |
| Lithological Description: |
Sandstone, fawn to pale brown, coarse- to very coarse-grained, lithic arkose to subarkose with pebbly horizons, thin to very thick beds; slumped cross-bedded channels, basal conglomerate with calcrete nodules. |
| Definition of Lower Boundary: |
Variable; either resting unconformably on Dalradian Supergroup metamorphic rocks or unconformably overstepping older Carboniferous strata, everywhere with a basal conglomerate. |
| Definition of Upper Boundary: |
Fining upwards into heterolithic alternating shales, siltstones and thin sandstones; succeeded abruptly and conformably by either peritidal carbonates of Termon River Limestone Formation or sandstones of Bin Mountain Sandstone Formation. |
| Thickness: |
0 to at least 350m |
| Geographical Limits: |
Kesh-Omagh area of the northwest Carboniferous basin of Ireland. |
| Parent Unit: |
Tyrone Group (TYRO)
|
| Previous Name(s): |
Claragh Sandstone Group [Obsolete Name and Code: Use CLSG]
(-136)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Reference Section |
Exposure in the Termon River at Gortnaree. Top beds exposed below the Termon River Limestone Formation. |
| Reference Section |
Basal conglomerate overlying Dalradian Supergroup metamorphic rocks exposed in field ridges, 700 metres northeast of Lough Chil. |
| Type Area |
Large area of exposed ground west of Scraghy and Altgolan townlands on the Kesh-Castlederg Road, particularly at Carricka Holten and Meenclogher, centred on Grid Squares H 20 76 and H 20 74 respectively. |
| Reference(s): |
| Simpson, I M, 1954. The Lower Carboniferous stratigraphy of the Omagh Syncline, Northern Ireland. Quarterly Journal of the Geological Society of London, Vol.110, 391-408. |
| Mitchell, W I, Johnston, T P and Legg, I C. 2004. Geology of the country around Kesh, Co. Fermanagh and Omagh, Co. Tyrone. Geological Sheets 32 and part of 31 (Kesh) and 33 (Omagh). Geological Survey of Northern Ireland. Technical Report GSNI 04/1. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
N32
|
