Siliceous-Pelagic sediments are rich in the remains of diatoms, silicoflagelattes and radiolaria. They occur most commonly below the CCD and in areas around the Antarctic and tropical and coastal upwelling zones where extremely high production of siliceous organisms occurs resulting in great export production of siliceous microfossils. Note that there is no such area in the GIN Seas or the North Atlantic because the diluting effects of large amounts of terrigenous and carbonate material in sedimentary water depth that are above the CCD here.

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