| Sandrock Formation | |
| Period: | Aptian |
| Type: | Geological formation |
| Prilithology: | Sandstone, siltstone, mudstone |
| Unitof: | Lower Greensand Group |
| Underlies: | Monk's Bay Sandstone Formation |
| Overlies: | Ferruginous Sands |
| Thickness: | up to 70m (230feet) |
| Map: | IOW_geology.svg |
| Region: | Europe |
| Extent: | Isle of Wight, Dorset |
The Sandrock Formation is a geological formation in England, part of the Lower Greensand Group, it is found on the Isle of Wight and in the northern part of Swanage Bay. It consists of a cyclic rhythm of sandstones, siltstones, and mudstones.[1]