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BARBERTON GREENSTONE BELT

20th March, 2024 Geography

BARBERTON GREENSTONE BELT

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Context

Geologists have found that the rocks of the Barberton Greenstone Belt are similar to those subjected to earthquakes and landslides in New Zealand. 

Details

Barberton Greenstone Belt

  • The Barberton Greenstone Belt, situated in northeastern South Africa, is a globally significant geological formation renowned for its ancient origins, rich mineral deposits, diverse ecosystems, and profound scientific importance.
  • Age: Rocks in the 3.55 to 3.22 Ga Barberton Granite Greenstone Terrain (BGGT), South Africa and Swaziland, represent one of the oldest, well-preserved pieces of continental crust on Earth.

Research and Findings in the Barberton Greenstone Belt

  • Geologists explored the Barberton Greenstone Belt in southern Africa, a significant geological formation.
  • This belt offers a crucial geological record spanning between 3.2 and 3.6 billion years ago.

Similarities to Younger Rocks in New Zealand

  • Researchers noticed striking similarities between the Barberton Greenstone Belt and younger rocks in New Zealand.
  • Specifically, similarities were found with rocks along the Hikurangi subduction zone, which have experienced earthquake-triggered submarine landslides.

Geological Observations and Interpretations

  • The Barberton Greenstone Belt presents challenges due to its complex geology.
  • Researchers struggled to trace the rocks through the landscape.
  • A partial map of the belt, published in 2021, revealed a disordered arrangement of blocks detached from their original formations.
  • The Great Marlborough Conglomerate, found in the Hikurangi subduction zone, shares similarities with bedrock in the Barberton Greenstone Belt.
  • Both areas have experienced significant geological activities, including earthquakes and submarine landslides.

Implications for Earth’s Early History

  • The Great Marlborough Conglomerate formation suggests a prolonged period of seismic activity over millions of years.
  • Each earthquake may have shifted large blocks of rocks, leaving a geological record of continuous shaking.
  • Plate tectonics likely began before 2 billion years ago, although the exact timing remains uncertain.
  • Earth’s early seismic activity could have coincided with the emergence of life.

Relationship to the Origin of Life

Role of Subduction Zones

  • Subduction zones, like the Hikurangi subduction zone, are not only sites of significant earthquakes but also host massive volcanic eruptions.
  • These extreme geological events might have created conditions favorable for the emergence and survival of life on Earth.

The Violent Birth of Life

  • Lead author Simon Lamb suggests that life could have emerged from the extreme geological violence associated with subduction zones.

PRACTICE QUESTIONS

Q.Barberton Greenstone Belt a geological formation recently seen in news is located in which country?

  1. South Africa
  2. USA
  3. Australia
  4. New Zeeland

Answer A