The Geological Survey of Northern Ireland carries out geological surveys in Northern Ireland. The GSNI maintains records from many different geological surveys and investigations carried out over the past 150 years. The core programme consists of the systematic geological mapping of Northern Ireland which is 70% complete. Currently the GSNI is mapping in the Sperrins and on the Antrim Plateau. In recent years the GSNI has co-ordinated geochemical and geophysical surveys in Northern Ireland.
 

The results of the geological mapping are produced as maps at a range of scales from 1:10 000 to 1:250 000, together with accompanying explanatory reports and memoirs. Geophysical and geochemical data are displayed as contour maps and /gsni/images, and tabulated data are often incorporated into reports.

Data are becoming available in digital format supplied under digital licence conditions.

The maps produced are the result of the observations and interpretation of a team of experienced geoscientists. The accompanying reports describe the results of the data with a limited amount of interpretation. The GSNI's geologists can provide more detailed interpretations of the survey results tailored to the needs of individual customers.