Application of GPR for geological mapping, exploration of industrial mineralization and sulphide deposits

The ground penetrating radar (GPR) technique is applied to the localization and characterization ofrock types, mineralizations and their associated boundaries, and to the identification of features inside the rock. This is made possible through the determination of variations of electrical properties within the rock units. GPR has been extensively tested at several localities in Sweden and Denmark. The main testing area in Sweden has been several sites in the Skellefte field. The Skellefte field is well known as the biggest sulphide mining district in Scandinavia. The testing area consists mainly of volcanic rocks surrounded by granites of various ages. Test measurements at the Skellefte mining areas are compared directly to geological variations in the rock as they have been exposed through the exploration activities. Electrical property contrasts between orebodies and the host rock gives possibilities of determining the distribution of shallow mineral resources. A combination of the variation in reflection pattern, reflection amplitude and penetration depth is used to determine the boundaries between different rock units. Reflection measurements have been used to identify both fracture zones as well as alteration zones and to determine their location and orientation. Lithological variations of limestone have been studied within the Faxe Kalk exploration area in Sjelland, Denmark. Divisions of the limestone into areas of coral reefs and lagoon deposits are made possible through distinctive reflection patterns and differing penetration depths between the rock units. The effect of tectonics can be studied by means of various reflection patterns from flint horizons within the lagoon deposits. The GPR results are used as a basis for geological modelling and as a foundation for mineral exploration activity.