Mapperley Park is entirely underlain by rocks of Triassic Age, having been deposited in a continental environment, some 225 m. years ago. The Trias in Britain was originally considered equivalent to the Bunter Sands and Keuper Marls of the Trias in Germany. Restricting the extent of our studies to the land forming the estate of the late E. Patchitt; the sandstone in the area adjacent to Mansfield road was known as the “Sand Fields” and the rising ground to the East of this the “Clay Fields”. In 1980, The British Geological Survey abandoned the old names of Bunter and Keuper and replaced them with the terms Sherwood Sandstones and Mercia Mudstones; based on spore analysis and the ability to correlate the British and German Trias using cores from boreholes sunk for oil and gas in the North Sea.
The top beds of the Sherwood Sandstones are called the Nottingham Castle Formation, based on Castle Rock. It outcrops in the Rock Cemetery at the junction of Mansfield Road and Forest Road; St. Andrews Church is built on the site of an old sand quarry; and there is a Sandstone cliff in the garden of No. 2 St. Andrews Road.
Two recent observations confirm the presence of Sandstone at the lower end of Mapperley Road. Excavations during the laying of television cables at the junction of Chestnut Grove and Mapperley Road and in the front garden of 14 Chestnut Grove both revealed Sandstone.
The rest of Mapperley Park is underlain by Mercia Mudstones The lowest beds are the Sneinton Formation, above this is the Radcliffe Formation and above this the Gunthorpe Formation. They are largely composed of red-brown marls with beds of grey-greenish fine grained silt and sandstones.
Following the demolition of Cheverton Court at the Woodborough Road end of Cranmer Street, prior to the erection of new apartment blocks; some 20m of grey Sandstones with red clay layers were exposed in the “High Wall” of the site. A geological fault explains the occurrence of this thickness of Mercia Mudstones so close to the Castle Sandstone. In detail, a number of parallel faults have been mapped, but the net effect of the fault zone is to down throw the base of the Sneinton Formation relative to the Nottingham Castle Formation. This line of faulting can be related to the Cinderhill Fault, known in mine workings at the former Cinderhill Colliery; and can be traced in a NW-SE direction towards the Vale of Belvoir. This fault zone crosses the South Eastern part of the Estate. Magdala Road (which runs parallel with Redcliffe Road) is underlain by a natural sequence from the Sandstone to the Mercia Marls.
- (1) B.G.S. 1:10k map SK 54 SE
- (2) B.G.S. memoir for 1:50k Sheet 125
- (3) B.G.S. memoir for 1:50k Sheet 127
- (4) Warrington et.al. 1980. A correlation of Triassic rocks in the British Isles Special Report of the Geological Society of London