Ocean Deposits

The ocean floor is covered by a variety of sediments, which provide valuable clues about the Earth's history and the dynamic processes shaping our planet. These sediments are classified based on their origin:

• Terrigenous Sediments
  • Derived from the weathering and erosion of rocks on land.
  • Transported to the ocean by rivers, wind, glaciers, and gravity.
  • Commonly found near continental margins.
  • Examples: Sand, silt, clay
• Biogenous Sediments
  • Derived from the skeletal remains of marine organisms.
  • Commonly found in areas of high biological productivity.
  • Two main types:
    • Calcareous oozes: Composed primarily of calcium carbonate shells of organisms like foraminifera and coccolithophores.
    • Siliceous oozes: Composed primarily of silica shells of organisms like diatoms and radiolarians.
• Hydrogenous Sediments
  • Formed by chemical reactions within seawater.
  • Examples include manganese nodules, phosphorites, and metal sulfides.
• Cosmogenous Sediments
  • Derived from extraterrestrial sources, such as meteorites and cosmic dust.
  • Relatively rare and typically found in small amounts.

The study of ocean sediments provides valuable insights into past climate change, ocean circulation patterns, and the evolution of marine life.