Tadcaster Magnesian Limestone 3-D borehole interpretation and cross-sections study
This report was prepared under contract to the Environment Agency and describes the geology 
of the area surrounding Tadcaster in North Yorkshire. The work was commissioned to 
investigate the local geology and construct 3-D cross-sections from borehole and surface 
information. Approximately 1200 boreholes were utilised for the work and these ranged in depth 
from a few metres to 350m. Five cross-sections were constructed; three WSW-ENE trending 
sections and two NNW-SSE trending sections all to a depth of 250m below OD. 
In addition, a series of thematic maps were generated from the lithological component of the 
digital borehole data. Total superficial aquifer and superficial aquitard maps show how the 
lithological nature of the superficial sequence varies across the area. Rockhead elevation and 
superficial thickness maps indicate where the bedrock aquifers outcrop or are near to the ground 
surface. 
The east side of the Vale of York in the vicinity of Tadcaster is underlain by a sequence of 
Permian and Triassic rocks overlain in part by thick superficial deposits dating mainly from the 
last Ice-Age. The Permian rocks comprise two magnesian limestone aquifers separated by 
sequences of gypsum/anhydrite and gypsiferous mudstones. The overlying Triassic rocks 
comprise the major Sherwood Sandstone aquifer. The western part of the area consists of mainly 
exposed bedrock (Permian dolostone and dolomitic limestone), but the eastern side where the 
Sherwood Sandstone Group is present has a thick cover of superficial deposits including 
moraines, glacial lake deposits and alluvial deposits.