Soil Parent Material Model (PMM)

National Catchment Site
Parent Material Map

A parent material is a soil-science name for a weathered rock or deposit from, and within which a soil has formed. In the UK, parent materials provide the basic foundations and building blocks of the soil, influencing their texture, structure, drainage and chemistry. Soils are the result of weathering processes that occur on the Earth’s surface where the atmosphere meets the geosphere and hydrosphere. We live in this ‘critical zone’ relying on our soils to grow our food and sustain the biodiversity and health of our environment.

We are developing a national digital Parent Material Model (PMM) at 1:50 000 scale, detailing the distribution of physiochemical properties of the weathered and unweathered parent materials of the UK to:

  • facilitate spatial mapping of UK soil properties
  • identify soils and landscapes sensitive to erosion
  • provide a national overview of our soil resource
  • develop a better understanding of weathering properties and processes

Applications

PMM data has already been used to provide information about ground conditions for installation of earthing conductors for electricity substations and for identifying key habitat characteristics of chalk downland soils. The PMM project is currently developing new data content to address issues such as ‘excavatability’ of sub-soils, their drainage characteristics and their bulk mineralogy. The data is also being assessed for its use in forensic science.

The PMM dataset is designed to be used by environmental researchers modelling nearsurface characteristics using standard GIS techniques. A wide range of environmental industries will benefit from using this dataset to assess baseline soil-geology characteristics. In the longer term, this data will assist UK businesses and public sector organisations to meet European Framework directives and regulations for soils.

Climate change study

A national-scale model will promote the study and coupling of the atmosphere–geosphere interaction thereby leading to a better understanding of the long-term impact of climate change on our environment. Soils in the UK support an extraordinarily diverse ecosystem, a better understanding of the soils and their parent materials will assist in identifying the soils most sensitive to the impacts of climate change.

Data content

The Parent Material Model details over 30 rock and sediment characteristics; it builds upon the standard DiGMapGB-50 geological dataset, adding simplified classifications of lithological properties. The project is also developing improved datasets for identifying key areas of peat, colluvium and aeolian deposits.

Dataset availability

The PMM map dataset is in the final stages of testing and will be made available to the public via BGS Digital Data Licensing by April 2010. E-mail DigitalLE@bgs.ac.uk for further information and pricing.

Contact:

For more information about the Parent Material Modelling Project contact Russell Lawley.