Exploration of Polymetallic Nodules and Polar Vortex (Download PDF)

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India’s rights to explore Polymetallic nodules from seabed in Central Indian Ocean Basin (CIOB). Extended by five years by International Seabed Authority, till 2022. India became the first country to have received the status of a pioneer investor in 1987.

  • Presently having an area of 75,000 square km, located about 1600 km away from her southern tip.

GSI (Geological Survey of India)

  • Presence of micro manganese nodules around Lakshadweep Sea.

  • Confirmed presence of Phosphate sediment off Karwar, Mangalore and Chennai coast.

  • Gas Hydrates in Mannar Basin and Cobalt bearing Ferro manganese crust from Andaman Sea.

Polymetallic Nodules and the Polymetallic Nodules Programme (PNP)

  • Also called manganese nodules.

  • Rock concretions formed of concentric layers of iron and manganese hydroxides around a core.

  • They contain nickel, copper, cobalt, lead, molybdenum, cadmium, vanadium, titanium and rare earth metals besides manganese and iron.

  • PNP orientation is towards exploration and development of technologies for eventual extraction of nodules from the Central Indian Ocean Basin (CIOB) allocated to India.

Consists of

  • Survey and Exploration.

  • Environmental Impact Assessment (EIA) Study.

  • Technology Development (Mining).

  • Technology Development (Extractive Metallurgy).

Polar Vortex

  • Is a large area of low pressure and cold air?

  • Surrounding both of the Earth’s poles.

  • A whirling mass of cold air circulating in the mid- to upper-levels of the atmosphere.

  • Flow is counter-clockwise.

  • Flow of air helps in containing the colder air within the poles.

Polar Vortex” event

  • It helps keep a current of air (the jet stream) travelling around the globe in almost a circular path.

  • Current contains the cold air north of it and the warm air south of it.

  • The polar vortex sometimes becomes less stable and expands during the winters.

  • Lack of a strong low-pressure system.

  • Results in resulting in jet stream losing the hold to keep it in line, and becoming wavy.

  • During a polar vortex event wave of cold air will be pushed down south.

  • Not confined to the US.

  • Cold surges are experienced by portions of Europe and Asia.

Earthquake Swarm in Palghar, Maharashtra

  • The Palghar district is in northern Maharashtra.

  • An unusual frequency of earthquakes since November, 2018.

  • 30 low-intensity earthquakes since November 2018- Dahanu town in Maharashtra’s Palghar district.

  • Magnitudes of the quakes ranged between 3 and 4.1 on the Richter scale.

  • Data collected points towards an “earthquake swarm”.

Earthquake Swarm

  • A series of many (sometimes thousands) low magnitude earthquakes.

  • There is no presence of a discernible main shock.

  • Occur in a localized region and over a period of time ranging from days, weeks to even months.

  • There is no clear sequence of foreshocks, main quakes and aftershocks.

  • Sometimes accompanied by acoustic or sound emissions.

Deccan Region and the Need for Caution

  • Sequences of low-intensity quakes are common in areas that have been hit previously. E. g. Saurashtra in Gujarat, Koyna in Maharashtra.

  • Also seen in areas without a history of seismic activity and, swarms are normal in peninsular India.

  • No mining activity has been found.

  • To explain the cause of earthquakes no mining activity has been found.

  • Along the Deccan plateau seismic waves travel faster in hard rocks which help the tremors dissipate faster.

  • Loose soil which makes the waves stay longer, release more energy and cause more damage.

  • Not limited to the Peninsula.

  • The Himalayan swarm was later attributed to low strength of the earth’s crust.

  • Identifying the quakes as a swarm would suggest there is little threat of a deadlier one hitting in the near future.

  • The possibility of either the quakes now subsiding or of a big one coming cannot be ruled out yet.

  • There is a need to draw up a community disaster management plan with Standard Operating Procedures by the district authorities.

Magnetic North Pole Shifting

  • Drifting fast away from the Canadian Arctic and towards Russia.

  • Geographic poles are being defined by the axis around which the planet rotates and are fixed.

  • The Earth behaves much like a giant bar magnet.

  • Behaviour defines its magnetic north and south poles.

Causes of the Magnetic Field

  • Earth’s magnetism lies in its outer core which is a more than 2,000-km layer surrounding the central core or the innermost part.

  • The magnetic poles do not coincide with the geographical poles due to the constant motion.

  • The magnetic behaviour of the Earth is far more complex than that of a simple bar magnet.

  • Outer core is comprised of liquid iron and some other metals like nickel.

  • Due to Earth’s rotation, the liquid iron is in constant motion and it is this motion which produces a magnetic field.

Recent Development

  • The magnetic north pole has been moving hundreds of miles across the Canadian Arctic towards Russia since 1831.

  • The pace of this movement has suddenly increased.

  • The World Magnetic Model (WMM) tracks the movement.

  • The faster movement of the magnetic north pole was responsible for WMM inaccurate such that it was about to exceed the acceptable limit for navigational errors.

Significance

  • The phenomena happening inside the earth can only be studied indirectly or through computer modelling.

  • There is no certainty about the fast movement.

  • The shifting of magnetic north pole would reveal insights into the phenomena happening deep inside the Earth’s surface.

Consequence

  • A standalone school compass will result in the reorientation of itself to the new resultant magnetic north pole.

  • The compasses used in modern instrumentation are much more sophisticated, digital and more accurate.

  • Dependence of the transportation sector especially aviation and shipping on the position of magnetic north.

  • The compass needs to be recalibrated to reflect the change in the magnetic north pole.

  • A set of software has been released by the WMM for updating the instruments to the new positions of the magnetic north pole.

- Published/Last Modified on: March 28, 2020

Geography

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