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Ocean Sediments. Paleoceanography. Figure 5-1. Ocean Sediments. Lithostratigraphy Biostratigraphy Chronostratigraphy Magnetostratigraphy Stable-isotopic stratigraphy. Foundations. Challenger Expedition (1872-1876) Baille rod German Meteor Expedition (1925-1927) Wolfgang Schott
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Ocean Sediments • Paleoceanography Figure 5-1
Ocean Sediments • Lithostratigraphy • Biostratigraphy • Chronostratigraphy • Magnetostratigraphy • Stable-isotopic stratigraphy
Foundations • Challenger Expedition (1872-1876) • Baille rod • German Meteor Expedition (1925-1927) • Wolfgang Schott • Foraminifera • Established first links between the abundance of marine organisms and climate
Foundations • Cesare Emiliani (1922-1995) • Isotopes of oxygen • First to demonstrate that ocean conditions were not constant through geologic time
Foundations • CLIMAP project (1971-1982) • Milankovitch Cycle • Eccentricity • Obliquity • Precession
IODP • Integrated Ocean Drilling Program
Descriptive Classifications • Granular • Fragmentation of organic or inorganic parent materials • Biogenous • Lithogenous • Chemical • Forming directly from dissolved compounds in seawater • Hydrogenous • Authigenic
Biogenous Sediments • Shells & skeletons • CaCO3 [calcareous] • SiO3 [siliceous] • Oozes
Biogenous Sediments • Coccolithophorids • Pteropods • Foraminfera • Diatoms • Radiolarians
Lithogenous Sediments • Terrigenous sediments • Fine to coarse • Most common • Weathering of rocks • Transport by rivers, winds, volcanoes and glaciers
Hydrogenous Sediments • Derived from chemical reactions in the water Hydrothermal Vent
Hydrogenous Sediments • Carbonates • Limestone-type deposits • Shallow, warm water • Ooliths
Hydrogenous Sediments • Phosphorites • Phosphorus in the form of phosphate • Continental shelf & slope
Hydrogenous Sediments • Salts • High rate of evaporation in shallow areas • Carbonate salts, sulfate salts, then chlorides
Hydrogenous Sediments • Manganese nodules • Manganese, iron, nickel, cobalt & copper
Cosmogenous Sediments • Sediments derived from space
Particle Size • Size & shape • Influences sinking rate and travel time
Particle Size • Particle aggregation • Electrical attraction • Fecal pellets 2200x