Makarov Basin - abyssal plain, 3800 m bsl on average (occasionally- over 4000 m, very close to the depth of the Nansen and Canada Basins), is mostly flat, disturbed only by 800 m-high linear ridge - abyssal continuation of the Marvin Spur. The potential fields anomalies illustrate the variety of structural plans of the Makarov Basin and surrounding regions. Gravity anomalies inside the Makarov Basin display symmetrical pattern relative to the linear positive anomaly parallel to 120°E, flanked by gravity lows on both side. The total thickness of the sedimentary cover varies from 2 to 4 km. The regional pre-Miocene unconformity RU at the base of the hemipelagic Miocene deposits is traceable through the whole Makarov Basin. The reduced Paleogene complex between the RU and post-Campanian unconformity pCU overlays the Upper Cretaceous and, possibly, older formations. Upper and lower crusts are estimated to be 3-6 km and 3-4 km, accordingly. Total crust thickness is 10-12 km.