The Tsaga gabbro-labradorite massif (the Kola Peninsula) shows possibilities of applying the complex interpretation of geophysical data in order to construct a structural-geological model of the intrusion and find the direction of future exploration work. The observed fields Δg and ΔZ (the survey scales were 1:100 000 and 1:50 000), results of seismic surveys and petrophysical data have been used. The studies have been carried out using numerical modeling, which for the first time made it possible to obtain quantitative estimates of the geological and structural position of Tsaga containing complex iron-titanium-vanadium ores. The undertaken studies, including correlation methods and transformations of the gravitational field, indicated that the massif looks like a plate-like body with the thickness of up to 3,5 km, continuing in the northeast and east directions beyond the known boundaries. In addition, we have identified 10 areas in its near-surface part, where widespread rocks with the anomalous density of 3,06-3,20 g/cm3 and the thickness of 0,8-1,1 km occur. They practically reach the surface and can host a titan-magnetite mineralization. The obtained results allow us to significantly expand the massif prospects to iron-titanium oxide ores using the identified areas where the high-density rocks were found.

Filatova Valentina Timofeevna, Lead Researcher, Geological Institute of the Kola Science Centre of the Russian Academy of Sciences, Dr. Sc. (Phys. & Math.). 14, Fersman str., Apatity, Murmansk region, 184209, Russia. E-mail: filatova@geoksc.apatity.ru.

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