Geophysical surveying

Geophysical surveying

Three different types of near-surface geophysical surveys were carried out at the Eddleston site to help explore the shallow geology of the site.

The techniques used were:

• electromagnetic induction (EM, also referred to as ground conductivity mapping)
• 2D electrical resistivity tomography (ERT) and
• ground penetrating radar (GPR)

Map of geophysical survey linesMap of the Eddleston site
showing the geophysical 'survey lines'.

This combination of electrical and electromagnetic (EM) techniques is a common application in investigations of shallow Quaternary deposits, and has been used successfully in a variety of recent BGS projects.

An example of a ground conductivity map.

The geophysical results were used to develop the 3D geological model of the site and to help decide where to site the floodplain boreholes.

Cross sections

The image below is an example of an ERT (electrical resistivity tomography) geophysical cross section across the floodplain/valley floor and the adjacent hill slope.

ERT example Example of an ERT (electrical resistivity tomography) geophysical cross section across the floodplain/valley floor and the adjacent hill slope.

Contact

Contact BGS Enquiries for further information.