Lanark Group
From Wikipedia, the free encyclopedia
TypeGroup
Unit ofOld Red Sandstone Supergroup
Sub-unitsGreywacke Conglomerate Formation, Swanshaw Sandstone Formation, Pentland Hills Volcanic Formation
UnderliesStrathclyde Group, Inverclyde Group
| Lanark Group | |
|---|---|
| Stratigraphic range: Silurian to early Devonian epoch | |
| Type | Group |
| Unit of | Old Red Sandstone Supergroup |
| Sub-units | Greywacke Conglomerate Formation, Swanshaw Sandstone Formation, Pentland Hills Volcanic Formation |
| Underlies | Strathclyde Group, Inverclyde Group |
| Overlies | North Esk Group |
| Thickness | up to around 2,500 m (8,200 ft) |
| Lithology | |
| Primary | sandstone |
| Other | conglomerates, calc-alkaline volcanic extrusive rocks |
| Location | |
| Region | Midland Valley |
| Country | Scotland |
| Extent | southern part of the Scottish Midland Valley |
| Type section | |
| Named for | Lanark |
The Lanark Group is a late Silurian to early Devonian lithostratigraphic group (a sequence of rock strata) in southern Scotland. The name is derived from the town of Lanark. It consists of sandstones and conglomerates within the Greywacke Conglomerate and Swanshaw Sandstone formations together with a wide range of igneous lithologies within the overlying Pentland Hills Volcanic Formation. The group is itself a division of the Old Red Sandstone Supergroup.[1]