MANTLE PLUME - GEOGRAPHY
News: Evidence of a giant mantle
plume found on Mars
What's in the news?
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Scientists have often considered Mars to be a dead
planet due to the lack of the geological activity that rocks Earth and Venus.
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However, a new study shows evidence of what could
be an active mantle plume beneath the
surface of the red planet.
Key takeaways:
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Published in Nature Astronomy, the study suggests a
more dynamic interior of Mars than previously thought.
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The recent study presented that there were multiple
lines of evidence that revealed the presence of a giant active mantle plume on
present-day Mars.
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Mantle plumes are large blobs of molten rock that rise towards the surface
from the interiors of a planet.
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According to the evidence found by the scientists,
the mantle plume is situated underneath a low-lying area called Elysium
Planitia that lies north to the equator.
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Though an otherwise indistinctive area, scientists
found unexpected evidence of geological activities in Elysium in the recent
past.
Mantle Plume:
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A mantle plume is an upwelling of abnormally hot rock within the Earth’s mantle.
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The heat from this extra hot magma causes melting
and thinning of the rocky crust, which leads to widespread volcanic activity on
Earth’s surface above the plume.
Role of Mantle Plume in
Plate Tectonics:
1. Creating Hotspots:
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The Hawaiian hotspot is one of the most well-known
examples of a mantle plume generating a hotspot.
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It has been active for millions of years, creating
a chain of volcanic islands. The volcanic activity of the Hawaiian hotspot has formed a series of volcanic islands, such as
the Hawaiian Islands, as the Pacific Plate moved over the stationary mantle
plume.
2. Island Chains and
Seamounts:
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The Hawaiian-Emperor
seamount chain is a prominent example of an island chain and seamount chain
created by a mantle plume.
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The chain extends from Hawaii to the Emperor
Seamounts in the northwest direction. The age progression of the volcanic
features in the Hawaiian-Emperor chain corresponds to the movement of the
Pacific Plate over the stationary hotspot, resulting in a trail of volcanic
islands and seamounts.
3. Plate Movement and
Direction:
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GPS measurements and satellite observations provide
concrete evidence of plate movements and velocities.
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Studies using GPS data have shown how the motion of
tectonic plates is influenced by the presence of mantle plumes, affecting their
speed and direction.
4. Formation of Large
Igneous Provinces (LIPs):
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The Siberian
Traps in Russia and the Deccan Traps in India are examples of large igneous
provinces linked to mantle plume activity.
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The Siberian Traps cover an area of about 2 million
square kilometers. The vast extent of lava flows in LIPs is attributed to the
immense volcanic eruptions associated with mantle plumes during significant
geological events.
5. Interaction with
Plate Boundaries:
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The East
African Rift is a well-known example of a plate boundary influenced by
mantle plume activity.
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The rift is a divergent boundary and is linked to a
mantle plume beneath the region.
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The presence of a mantle plume beneath the East
African Rift is believed to have caused the thinning and stretching of the
crust, leading to the formation of the rift zone.
6. Mantle Convection:
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Seismic tomography provides insights into the
movement of material within the Earth’s mantle.
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Seismic tomography data show patterns of upwelling and downwelling material, indicating the presence
of mantle convection and mantle plumes.
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These data facts demonstrate the significant role
of mantle plumes in plate tectonics, influencing the movement of tectonic
plates, creating volcanic features, and contributing to the dynamic processes
that shape the Earth’s surface and geological history.
7. Continental Rifting
& Volcanism:
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This association has given rise to the hypothesis
that mantle plumes play a significant role in the process of continental rifting and the formation of
ocean basins.
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However, an alternative “Plate model” posits that
continental breakup is an inherent aspect of plate tectonics, and massive
volcanism occurs naturally as a consequence during this phase.
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Explores the relationship between mantle plumes,
continental rifting, and the contrasting viewpoints regarding the origin of
massive volcanism during continental breakup.