Third Pole, Deep Earth and Blue Hole (Download PDF)

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In the region to the north of India and to the south of China. Region spreads across the Himalaya-Hindu Kush mountain ranges and the Tibetan Plateau. Contains the third largest expanse of frozen water on earth. Much smaller in area than the north or the South Pole.

  • Covers 100,000 square kilometers and has around 45,000 glaciers.
  • Altogether there are 10 Asian rivers that begin in the third pole. Some of them are the Yellow river and Yangtze River in China, the Irrawaddy River in Myanmar, the Ganges which flows through India and Bangladesh and the Mekong River.
  • Largest reserve of fresh water outside the two major polar regions.

Deep Earth

  • Region existing between 2 km and 3 km below the ocean-floor.
  • Consists of about 2 - 2.3 billion cubic km (about twice the volume of the oceans combined) .
  • Biosphere constitutes “Subterranean Galapagos” which includes members of all 3 domains of life – Bacteria, Archaea and Eukarya.
  • The earth is dominated by Bacteria and archaea (microbes with no membrane-bound nucleus.
  • As per the Scientists about 70 % of earth՚s bacteria and archaea live in the subsurface.
  • Found less in numbers
  • Eukarya
  • Multicellular organisms.
  • Cells contain a nucleus as well as membrane bound organelles.

Blue Hole

  • Roughly circular marine cavern or sinkhole.
  • Open to the surface.
  • Developed in a bank or island composed of a carbonate bedrock (limestone or coral reef) .
  • The blue color is due to the high transparency of water and bright white carbonate sand.
  • The water circulation is poor.
  • Commonly anoxic below a certain depth.
  • Some significant blue holes Dragon Hole - South China Sea, Great Blue Hole – Belize, Deans Blue Hole – Bahamas, Cenotes are inland voids usually containing fresh groundwater rather than seawater.

- Published/Last Modified on: March 28, 2020

Geography

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