During high-latitude combined geological and geophysical expedition “Arctic-2012”, deep seismic sounding (DSS) with ocean bottom seismometers were carried out in the Arctic Ocean along the line 740 km long, crossing the Mendeleev Rise at about 77° N. Crustal and upper mantle Vp-velocity and Vp/Vs-ratio models were constructed. Crustal section comprises: sedimentary cover, intermediate (metasedimentary) complex, upper crystalline crust, lower crystalline crust, upper mantle. Crustal thickness within the Mendeleev Rise is about 32 km; almost 20 km falls on the lower crust. In general, velocity parameters and crustal thickness on the Mendeleev Rise are typical of continental crust. Increased thickness of the lower crust may be related to magmatic underplating, which in turn led to intraplate mafic volcanism and
HALIP formation in this part of the Arctic.