The is the easternmost tectonic unit or terrane of Hokkaidō, Japan. The boundary with the Tokoro Belt to the west is marked by the , which runs from the area of Abashiri on the north coast to that of Urahoro on the south coast, the southern portion coinciding with the . The belt is composed of volcanogenic sediments and volcanic rocks — for the most part, basalt and andesites; these may be remnants of an island arc that took shape over an "east or southeast dipping intraoceanic subduction zone". As dated by potassium–argon geochronology and radiolarians, the oldest sequences are Campanian‐Maastrichtian. The belt has rotated counterclockwise some 15–25° since the Late Cretaceous.
Running roughly east to west, the primary rock strata of the Nemuro Belt are the Late Cretaceous (Campanian) to early Palaeogene (Palaeocene and, in places, Eocene) deposits of the , which occur in the and extend along the south coast from Kushiro and the Nemuro Peninsula into the South Kurils, to Zelyony (Shibotsu) and Shikotan, and perhaps as far as the submarine Vityaz Ridge. The Nemuro Group is in part overlain by the Middle Eocene , which is in turn overlain by the Upper Eocene to Lower Oligocene .
Nemuro Group The group includes the following formations, in ascending order:
Urahoro Group The group includes the following formations, in ascending order:
At the western end, the correlates with the Beppo, Harutori, and Tenneru Formations.
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