In the spring of 1931 Georgy Ushakov, accompanied by the geologist Nikolay Urvantsev, the veteran surveyor Sergei Zhuravlev, and the radio operator Vasily Khodov thoroughly surveyed Severnaya Zemlya during a two-year expedition to the archipelago. Ushakov and his team established a small base at Golomyanny – the western end of Sredniy Island, off October Revolution Island's western coast. From there they made multiple surveying trips into the interior and the coastlines of the larger islands. The first detailed map drawn by the expedition's cartographers showed Severnaya Zemlya to be divided into four main islands. Geographic features of the territory were named after communist organisations, events, and personalities. About Severnaya Zemlya Ushakov wrote: