Occurrence of interlayers in sediment cores collected in the East Indian Ocean

Similarity of distribution of tephra, tuffaceous sediments, Ethmodiscus ooze, and turbidites in the Pleistocene section results from deposition of all these materials under controll of a single factor, namely synchronous redistribution owing to seismic activity on the ocean floor and on the Sunda Islands.

Burial of layers of oxidized deposits and formation of iron-manganese nodules is at least partly related to global climate cooling and to circulation of ocean waters.