Eocene sand horizons & iron contamination mapping | Thames Basin streams

Sampling from an iron-rich stream in Berkshire

Laboratory work at the Imperial College field station at Silwood Park, Berkshire

The BGS has mapped metal concentrations in streams and stream sediments in the UK in recent years, e.g. baseline geochemical mapping of Great Britain and Northern Ireland G-BASE

The mapping of southern England, the final part of the survey, was in progress during the summer of 2009. A particular feature of the work has been the involvement of students on vacation to assist with collecting field data.

Imperial College study

A related, but independent, study in southern England has been carried out over the last ten years employing the input of MSc and MSci students from Imperial College London.

In this study iron concentrations have been determined in streams associated with Eocene sands covering some 600 km2 of Berkshire, Surrey and north-east Hampshire to the west of London.

An A0-size map of iron contamination in streams in this area has been produced based on relevant BGS-digitised 1:50 000 solid and drift geology and ArcGIS representations. Download the Eocene sands and iron contamination A0 map or learn more about the background and theory .

A paper describing the Imperial College study in more detail is planned for GEEA in 2012. The paper includes the methodologies employed together with a discussion, an A4 version of the map, and assessments of the hydrological and geochemical mechanisms controlling iron release from the sand horizons. Environmental impacts of iron contamination are also considered.


Further information about the Imperial College study contact Dr Philippa Mason, Dr Bill Dudeney or Julia Barrott