Give a classification of ocean deposits on the basis of sources.

Classification of Ocean Deposits (महासागरीय निक्षेप) on the Basis of Sources:

Ocean floor sediments are systematically classified by Sir John Murray into Four Source Categories:

• 1. Terrigenous Deposits (स्थलजात निक्षेप - Land-Derived):
  • Formed by denudation and riverine transport of continental rocks; deposited on continental shelves/slopes. Classified by grain size: Gravel, Sand, Silt, Clay, and Mud (Blue Mud, Red Mud, Green Mud containing glauconite).
• 2. Pelagic / Biogenous Deposits (जैविक निक्षेप - Organic Marine Remains):
  • Composed of skeletons and shells of microscopic pelagic organisms forming deep-sea "Oozes":
    1. Calcareous Oozes: Rich in calcium carbonate; dissolves at depths $>4,000 ext{ m}$ (CCD); e.g., Globigerina Ooze, Pteropod Ooze.
    2. Siliceous Oozes: Formed in cold deep waters; e.g., Radiolarian Ooze, Diatom Ooze.
• 3. Hydrogenous / Inorganic Deposits (अकार्बनिक रासायनिक निक्षेप):
  • Chemical precipitates on abyssal plains; e.g., Red Clay (लाल मृतिका - covers ~38% of ocean floor) and Polymetallic Manganese Nodules.
• 4. Cosmogenous & Volcanic Deposits: Extraterrestrial meteoritic dust and submarine volcanic ash/pumice.