Figure 3. Crustal sections of the southern part of the Gakkel Ridge obtained by airborne magnetic data [{\it Rzhevsky,} 1975]. 1 - upper mantle, 2 - basaltic layer, 3 - granitic layer, 4 - consolidated deposits, 5 - unconsolidated deposits, 6 - volcanic-sedimentary strata of the rift valley, 7 - water, 8 - weakened zone of uncertain genesis, 9 - plot of anomalous magnetic field DTa , 10 - depth of the upper edges of magnetic bodies, 11 - depth of the lower edges of magnetic bodies.