Deep Sea Sediments Photomicographs courtesy of Paula Worstell, Scripps Institution of Oceanography and BOSCORF, National Oceanographic Center, Southampton, UK and Ocean Drilling Program See: for more information on sedimentary regimes of the Pacific basin.

SUBEQUATORIAL PACIFIC OCEAN Water depth 5399m 3ºN, 165ºW Sample Ref: PROA- 131G-2, Top Courtesy: Paula Worstell, SIO Description: Radiolarians, as seen here, are abundant in sediments along an equatorial band in the Pacific Ocean. Diatoms are also present in this sample. High power (x100) view. Radiolarian ooze with some diatoms

Brown Pelagic Clay with porcelanite laminae, from South Pacific gyre, IODP Exp 329. This sediment is similar to that found in the North Pacific gyre illustrated in Figure 4 in the mini lesson (Cazfoto)

Pelagic Brown Clay NORTH PACIFIC OCEAN Water depth: 4940m PPL 25ºN, 162ºW Sample Ref: JYN2-1G, Courtesy: Paula Worstell, SIO (4) Deep sea red clay with sponge spicules Description: This deep-sea clay contains a few siliceous sponge spicules. High power (x100) view.

Siliceous Mud Diatom clay with some radiolarian fragments. High power (x100) view. North Pacific, 47ºN, 164ºW Sample Ref: CHIN-6G, Top Courtesy: Paula Worstell, SIO

Terrigenous Mud Back-Scattered Electron microscope image of terrigenous mud. Sediment from Alboran Sea, ODP Site 976B, 556 m below seafloor. Note foraminiferal fossils plus obvious angular quartz grains. This type of sediment is a mixture that could be derived from a continent and include fossils from the open ocean Source: OPD and Wikepedia

Chalk or lithified calcareous ooze. This could be similar to the type of sediment accumulating in an open ocean environment on a high area such as a seamount. (source Wikipedia)