An important task for the White Sea region, Russia’s second largest diamond-producing province, is the search for magmatic bodies overlapped by sedimentary cover via magnetometer survey. The models, linking local and magnetic anomalies with their sources, are essential for interpretation of search results. The aim of the study is to build a 3D magnetic model of the Earth’s crust for the White Sea region using aeromagnetic data and the modeling technologies of the Integro software package. The simulation is basing on a digital map of the pole-reduced anomalous magnetic field. The sources of magnetic anomalies are believed to be located in the Earth’s crust. The researchers obtained 3D distribution of the relative magnetic susceptibility of rocks by solving the inverse problem of magnetic prospecting. To separate the magnetic sources by spatial frequencies and depth, the model magnetic field was recalculated upward, as well as the TDR derivatives, which determine the lateral boundaries of the sources of positive magnetic field anomalies, were calculated. The researchers further analyzed 2D distributions of the magnetic sources of the model for vertical and horizontal sections with depths of 10, 15 and 20 km, thus proving the relationship between the surface and deep structures of the magnetic sources of the Earth’s crust in the region.

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The study area is the White Sea basin and adjacent territories. The relevance of the work carried out here is determined by active geodynamics, kimberlite magmatism, and prospects for the hydrocarbon search. The authors set the goal to model the velocity structure of the region’s crust using data from instrumental observations and the Integro software package. A comprehensive interpretation of gravimetric, magnetometric, seismic, petrophysical and geological data has been carried out. With the help of 2D models based on the DSZ profiles and digital maps of geophysical fields, refined density structures of local sections of the earth’s crust have been specified. The developed 3D density model gives a general picture of the deep structure of the region’s crust. Within its framework, the spatial positions of the layers of the velocity reference model are determined and their connections with density inhomogeneities and geophysical anomalies are established.