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The conductivity structure of the Earth’s mantle was estimated using the induction method down to 2100 km depth for the Europe–Asia region. For this purpose, the responses obtained at seven geomagnetic observatories (IRT, KIV, MOS, NVS, HLP, WIT and NGK) were analysed, together with reliable published results for 11 yr variations. 1‐D spherical modelling has shown that, beneath the mid‐mantle conductive layer (600–800 km), the conductivity increases slowly from about 1 S m−1 at 1000 km depth to 10 S m−1 at 1900 km, while further down (1900–2100 km) this increase is faster. Published models of the lower mantle conductivity obtained using the secular, 30–60 yr variations were also considered, in order to estimate the conductivity at depths down to the core. The new regional model of the lower mantle conductivity does not contradict most modern geoelectrical sounding results. This model supports the idea that the mantle base, situated below 2100 km depth, has a very high conductivity.

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