f Landfill monitoring by airborne EM and ground resistivity measurements

Geological Survey of Finland (GTK) carries out systematic airborne geophysical surveys in Finland using flight altitude of 30-40 metres and line spacing of 200 metres ( Lohva et al, 1996; Peltoniemi, 1986). The following systems are in use: magnetic, gamma radiation and electromagnetic (AEM). The electromagnetic unit is a dual-frequency vertical coplanar the coil equipment (Poikonen et al, 1998), frequencies are 3.1 kHz and 14.4 kHz and coil separation 21.4 m. AEM dual frequency results are most suitable for classification of environmental effects to locate possible leakages from landfills (Jokinen et al, 1998). Examples of environmental applications of airborne geophysics in Finland is presented in paper by Lerssi et al, 1997.