. The depths of the ocean : a general account of the modern science of oceanography based largely on the scientific researches of the Norwegian steamer Michael Sars in the North Atlantic. "Michael Sars" North Atlantic Deep-sea Expedition (1910); Oceanography; North Atlantic Ocean. f^^^ Fig. 138.—Globigerina Ooze. Station 162, Southern Ocean, lat. 43° 44'. 4 S. Valdivia long. 75" 33'-7 E. 1878 fathoms (magnified). 164 DEPTHS OF THE OCEAN the shells of all these species may occur in the Pteropod ooze, but the extent of this type of deposit is not great. Shelled ptero- pods, except
. The depths of the ocean : a general account of the modern science of oceanography based largely on the scientific researches of the Norwegian steamer Michael Sars in the North Atlantic. "Michael Sars" North Atlantic Deep-sea Expedition (1910); Oceanography; North Atlantic Ocean. f^^^ Fig. 138.—Globigerina Ooze. Station 162, Southern Ocean, lat. 43° 44'. 4 S. Valdivia long. 75" 33'-7 E. 1878 fathoms (magnified). 164 DEPTHS OF THE OCEAN the shells of all these species may occur in the Pteropod ooze, but the extent of this type of deposit is not great. Shelled ptero- pods, except Lijuacina, are not found in the polar oceans. Globigerina Ooze.— The average depth of the ocean is about 2000 fathoms, and the most widely distributed of the deposits in these average depths is Glo- bigerina ooze (see Figs. 137 to 139), which is made up largely of the dead shells of surface foraminifera, the genus Globigerina often greatly predominating, hence the name. About twenty species of pelagic foraminifera (see p. 172) inhabit the surface waters of the tropical oceans, and their dead shells are found in the Globigerina ooze ^ and also in the Pteropod ooze, but towards the Arctic and Antarctic regions only one or two dwarfed species occur in the surface and sub- surface waters. I n very deep water, even within the tropics, the calcare- ous shells do not accu- mulate on the bottom, 1 The names " Biloculina clay" and ." Orbulina ooze" will lie found in the literature of marine deposits, but these have been described from samples which had been passed through fine sieves, the larger shells having been retained while the smaller ones had passed through the Valdivia' long, Fi I )ozE. Station 154, Southern Ocean, lat. 6 61° 15'.9 E., 1940 fathoms (magnified). 45'.2 Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations m
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Keywords: ., bookcentury1900, bookdecade1910, bookpublisherlondo, bookyear1912
