S Engering, S and Barron, H.F. (2007) Doncaster Geodiversity Assessment Volumes 1&2. British Geological Survey Commissioned Report CR/07/025N. For planning purposes consult Doncaster City Council The report is also available as a PDF download from NERC NORA
A6 DR1 Denaby Woods/Mexborough Oxbow Lake
Site information
Site name: Denaby Woods/Mexborough Oxbow Lake
Site key: DR1
Grid reference:
Site type: geomorphological interest site
Local authority: Doncaster Metropolitan Borough Council, South Yorkshire
Site dimensions: several km2
Site owner: Various
Conservation status: Proposed Regionally Important Geological Site Date: No Date
Field surveyor: Scott Engering Date: 13/3/07
Stratigraphy and rock types
Time unit: Carboniferous, Westphalian Rock unit: Pennine Coal Measure Group
Rock type: Details:
Site map
This map is based upon Ordnance Survey topographic material with the permission of Ordnance Survey on behalf of The Controller of Her Majesty’s Stationery Office, © Crown copyright. Unauthorised reproduction infringes Crown Copyright and may lead to prosecution or civil proceedings. Licence Number: 100017897 [2007]
Site description
The area around Mexborough and Old Denaby is of particular interest in a regional context for landforms and topography that provide evidence of two major structural geology features: the Don Monocline and the South Don fault. These have also influenced the drainage patterns of the River Don and the River Dearne and in the low lying areas adjacent to these two rivers, there are river terraces, braided channels, oxbow lakes and wetlands that record the development of river systems during the Quaternary Period.
In general, the Coal Measures rocks that form the distinctive scarp and topography to the west of the Permian limestone escarpment posses a north-north-west–south-south-east alignment, with strata generally dipping to the north-east with progressively younger rocks outcropping in that direction. In the Doncaster region, this is seen at Barnburgh and from viewpoints at Conisbrough, Cadeby, High Melton and Hooton Pagnell, this pattern is clearly seen in the landscape and by following the course of the River Dearne. However, from Sheffield, Rotherham and into the region between Hooton Roberts and Old Denaby, the strata immediately to the south of the course of the River Don are aligned south-south-west– north-north-east, with strata dipping steeply to the south-east and form distinct escarpments of Mexborough Rock and Ackworth Rock at Denaby Wood and a much smaller, but very distinctive, escarpment, also Mexborough rock, south of the Don at Mexbrorough (centred on
The alignment and form of these escarpments is closely associated with the south-south-west–north- north-east Don Fault System and the outcrop of these strata has controlled the course of the River Don and the position of associated alluvial terraces. At
In a regional context, linking with biodiversity initiatives and existing Nature Reserves, the area merits further protection for its geological and geomorphological significance.
RIGS assessment of site value
Ratings: 1–2 very poor; 3–4 poor; 5–6 acceptable/useful; 7–8 quite good; 9–10 very good/excellent; N/A not applicable; D/K don't know
Access and safety
Aspect/Description/Rating
Road access & parking On street, roadside parking. The proposed site covers a large area and walking is required. Rating: 6
Safety of access Good access. Involves walking around wetland areas and associated paths. Rating: 7
Safety of exposure Reasonable precautions required around wetland areas ie good footwear etc.. Rating: 7
Permission to visit Ferryboat Farm Fisheries is private. Points of interest viewed from public rights of way. Rating: 5
Current condition Areas of interest are in good condition but lie in and around areas that are rapidly developing. Rating: 7
Current conflicting activities Development
Restricting conditions Private access to some parts. Possibility of opening new pathways etc
Nature of exposure Escarpments and geomorphological and topographic features
Multiple exposures /prospect for trail With proper management and access, there are good prospects for education at a variety of levels and trails. Links to hard rock geology on Permian limestone
Notes Most features viewed from public rights of way
Culture, heritage & economic
Aspect/Description/Rating
Historic, archaeological & literary associations Settlement patterns associated with the confluence of the River Don and Dearne e.g. Mexborough castle. Rating: 7
Aesthetic landscape Excellent site, with scarp topography and other rural features within an are dominated by industrial development. Rating: 9
History of earth sciences Regionally significant for demonstrating the Don Monocline and Don faults. Rating: 9
Economic geology Not applicable. Rating: 0
Notes Settlement patterns associated with confluence of the Don and Dearne
Education and science
Surface processes Meandering, alluvial terraces, oxbow lakes, river drainage patterns, fluvial processes. Rating: 7
Geomorphology Fault bound escarpments and fluvial landforms. Rating: 8
Sedimentary Fluvial processes. Rating: 8
Fossils Not applicable. Rating: 0
Igneous Not applicable. Rating: 0
Metamorphic Not applicable. Rating: 0
Tectonic: structural Evidence of the Don Monocline and Don Fault System. Rating: 9
Minerals Not applicable. Rating: 0
Stratigraphy None known. Rating: 0
Notes Excellent site to demonstrate Don Monocline and associated faulting and river channel processes
Geodiversity value
Very good. Faulting and folding, alluvial processes and geomorphology. Rating: 9