Ocean Ch 4

  1. Lithogenetic Sediment...
    derived from the chemical and mechanical breakdown (weathering) and erosion of rock material; mostly derived from land (terrigenous) Lithogenetic sediments are carried off the continents by wind, water, gravity and ice into the ocean basins, and makeup 3/4 total marine sediment.
  2. Running water in stream channels..
    is the most important "delivery" agent of sediment to ocean basins. When land derived sediments reach the oceans margins they are dispersed by coastal wave action and ocean currents.
  3. Sediment is transported by streams to ocean basins by...
    Bed load; Suspended load; and Dissolved load
  4. Bed load is...
    coarser grained material (mostly granules, sand and silt transported along the bottom of a stream channel.
  5. Suspended load
    mostly fine grained clay sized material, continuously suspended in the water.
  6. Dissolved load..
    by products of the chemical weathering of rocks, calcium, potassium, sodium, magnesium, bicarbonates, dissolved by the water.
  7. Particles that accumulate on the sea floor are called...
  8. Accumulation of sediment on the seafloor also vary in the range of grain size, known as...
  9. Tephra...
    Sediment derived from explosive volcanism.
  10. Weathering...
    The physical disintegration, chemical decomposition, or solution of exposed rock which takes place where the lithosphere (mainly the crust) interfaces with the other Earth subsystems
  11. Erosion...
    Removal and transport of sediments by running water, glaciers, wind, or gravity.
  12. Fecal Pellets...
    Organic excrement found especially in marine sediment deposits and made up of the undigested organic matter secreted by animals.
  13. Biogenous Sediment...
    Includes the excretions, secretions, an remains of organisms. Examples; Shells, fragments of coral, and skeletal parts.
  14. Marine snow...
    the "Raining" of organic materials in ocean water.
  15. Hydrogenous Sediment...
    Encompasses particles that are chemically precipitated from seawater, in some cases forming coatings on other seafloor sediment.
  16. Manganese Nodules...
    precipitated on the deep seafloor as a bypruduct of hydrothermal heating of ocean waters. They range in size from fine grained to potato sized, and are made up of manganese, iron and lesser amoutns of copper, cobalt, and nickel.
  17. Cosmogenous Sediment...
    comes from outer space, for example, as meteorite fragments.
  18. Tektites...
    Droplets shaped shards of rock that crystallized of molten material that was ejected into the atmosphere during a meteorite strike on the earth's surface.
  19. Delta...
    Where sediments accumulate, at the mouth of a river delta. When water goes into the ocean from a stream, sediment accumulates from there.
  20. Wetlands..
    Are low-lying flat areas that are covered by water or have soils that are saturated with water for at least part of a year.
  21. Turbidity Currents...
    Near the mouths of many major sediment transporting rivers that empty into the ocean, intermittent avalanches of dense, mud rich waters flow down submarine canyons, carrying sediment onto the ocean floor. They are very powerful and can destroy submarines.
  22. Pelagic Deposits...
    Fine-grained sediments that gradually accumulate particle by particle on the deep ocean floor form these. They accumulate considerably slower than near shore sediments. (Deltas)
  23. Calcareous Ooze....
    Mostly made up of shells. Dissolved in seawater. (Coccoliths, foraminifera, pteropods.)
  24. Siliceous Ooze..
    is composed of tests of diatoms and radiolaria Ocean water is undersaturated with silica so that these shells dissolve at the ocean depths. Only where that source of organic material is abundant.
  25. Abyssal Storms..
    generated moving clouds of suspended sediment that bottom currents help move.
  26. Lithitification...
    usually involves both compaction and cementing of sediments relatively low temps. (Sediment gradually converting to a solid)
  27. Placer Deposits...
    Ocean waves and currents sort and concentrate metals and gemstones in coastal submarine deposits.
  28. Hjulstrom Diagram...
    Shows the relationship between the velocity of water and grain size and carrying capacity and carry competency of any current can be determined form the diagram. Using grain size, velocity, and erosion.
  29. the thickest deposits are...
    found on continental margins.
  30. Sediment textures and classifies based on...
    Grain size, phi scale, mm, Wentworth scale, roundness, and sorting.
  31. Ice Rafting..
    leading edge of the glacier produce icebergs that transport the glacial sediments into the deepest parts of the ocean basins in this process. help with prof of climate change.
  32. Pteropods..
  33. Silica-Chert made up of...
    Diatoms (Single celled algea)
  34. Gypsum..
    mostly on the margins of ocean basins as water is evaporated.
  35. Halite..
    Sodium Chloride (Salt). Mostly on the margins of ocean basins as evaporate deposits in salt flats (or sabkhas)
  36. Where are Manganese Nodules found?
    They are found on the depets abyssal plains and around mid-ocean ridges where both ligthogenetic and biogenetic sediments rates are low. Found on all seafloors except the Arctic.
  37. Continental margins are..
    considered transition environments.
Card Set
Ocean Ch 4