An oceanic plateau is a large igneous province (an area where the Earth's crust consists of flood basalt) on the bottom of an ocean. Oceanic plateaus are similar to areas of flood basalt on the land, such as the Deccan Traps or Siberian Steps. An oceanic plateau is higher than the surrounding seabed.
Since the ocean crust is richer in silica (felsischer) and lesser density than normal oceanic crust, it is believed that they are an intermediate stage in the formation of continental crust. When an oceanic plateau subdues, partial melting will produce silica-rich magma that is a subsequent stage in the formation of continental crust.
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