Why in news?

India has signed a new contract with the International Seabed Authority (ISA) granting exclusive rights to explore Polymetallic Sulphides (PMS) in the Carlsberg Ridge of the Indian Ocean. With this, India has become the first country in the world to hold two such ISA contracts, commanding the largest seabed area allocated internationally for PMS exploration.

The National Centre for Polar and Ocean Research (NCPOR), Goa, will begin exploration in 2026 through geophysical and hydrographic surveys. India’s application, submitted in 2024, was approved last week, allotting a 10,000 sq km area in the Carlsberg Ridge.

This builds on its earlier 2016 contract for exploration in the Central and Southwest Indian Ridges, marking both a scientific breakthrough and a strategic advantage.

What’s in Today’s Article?

• Polymetallic Sulphides and Their Importance for India
• India’s Experience in PMS Exploration
• Significance of the Carlsberg Ridge
• How PMS Exploration Differs from Other Underwater Mineral Searches?
• How ISA Allocates Mineral Exploration Sites?
• India’s Plans for Additional Mineral Exploration in the Indian Ocean

Polymetallic Sulphides and Their Importance for India

• PMS are rich seabed deposits containing copper, zinc, lead, gold, silver, and trace amounts of rare and precious elements.
• Found near hydrothermal vents on the ocean floor, these deposits form when seawater seeps into cracks, interacts with magma beneath the Earth’s crust, and resurfaces as mineral-rich hot water that solidifies on the seabed.
• For India, PMS exploration is vital as land-based reserves of such minerals are limited.
• Securing these resources is crucial for strategic industries, renewable energy systems, high-technology applications, and green technologies, thereby enhancing the country’s resource security and self-reliance.

India’s Experience in PMS Exploration

• Since signing its first PMS exploration contract with the International Seabed Authority (ISA) in 2016, India’s National Centre for Polar and Ocean Research (NCPOR) has carried out extensive surveys in the central and southwest Indian Ocean ridges, building significant expertise and infrastructure.
• The government’s Deep Ocean Mission has strengthened these efforts by adding deep-sea vessels, advanced tools like Autonomous Underwater Vehicles (AUVs).
• The upcoming Matsya submersible under the Samudrayaan mission, which will further expand exploration capacity.
• NCPOR follows a three-phase plan:
  • Reconnaissance surveys with ship-based tools to locate potential PMS sites.
  • Near-seabed surveys using AUVs and Remotely Operated Vehicles (ROVs) to confirm deposits.
  • Resource evaluation of identified PMS areas for assessing their economic potential.

Significance of the Carlsberg Ridge

• The Carlsberg Ridge, part of the mid-ocean ridge system in the Indian Ocean, was formed by seafloor spreading between the Indian Plate and Somali Plate about 40 million years ago.
• With a slow spreading rate of 2.4–3.3 cm per year, it features rugged flanking topography and a median valley typical of slow-spreading ridges.
• The ridge hosts hydrothermal vent systems, making it a potential hotspot for Polymetallic Sulphide (PMS) deposits.
• India has been studying these systems for over three decades.
• Strategically, its proximity — located near 2°N latitude, much closer to India than the Central and Southwest Indian Ridges at 26°S — makes it highly significant for resource security and scientific exploration.

How PMS Exploration Differs from Other Underwater Mineral Searches?

• PMS exploration is far more complex than other seabed mineral investigations.
• PMS deposits occur near hydrothermal vents along mid-ocean ridges, at depths of 2,000–5,000 metres, where the terrain is rocky, uneven, and remote.
• Survey operations require deep-sea vessels with dynamic positioning, precise navigation, and advanced communication systems.
• Unlike other explorations, PMS demands a multidisciplinary team of marine geologists, geophysicists, oceanographers, biologists, and deep-sea technologists.
• Exploration methods involve ship-mounted geophysical surveys for reconnaissance, and Autonomous Underwater Vehicles (AUVs) and Remotely Operated Vehicles (ROVs) for detailed near-seabed mapping and sample collection.
• Advanced tools are essential to accurately analyse mineral composition, making PMS exploration one of the most technically demanding deep-sea missions.

How ISA Allocates Mineral Exploration Sites?

• The International Seabed Authority (ISA), established under the UNCLOS framework, manages mineral exploration in international waters.
• Countries, through their governments, public sector bodies, or sponsored entities, apply to the ISA for exploration rights.
• Applications must include details of the proposed area, a work plan, environmental baseline studies, and proof of technical and financial capacity.
• The ISA’s Legal and Technical Commission (LTC) reviews these submissions for compliance.
• If approved, the application is forwarded to the ISA Council for final clearance, granting the applicant exclusive exploration rights in the designated seabed area.

India’s Plans for Additional Mineral Exploration in the Indian Ocean

• As part of its Blue Economy initiatives, India is pursuing more seabed mineral exploration rights in the Indian Ocean.
• Beyond its existing contracts for Polymetallic Sulphides (PMS), India has applied to the ISA for rights to explore cobalt-rich ferromanganese crusts on the Afanasy-Nikitin Seamount in the Central Indian Ocean. This application is currently under review.
• Securing such rights would further strengthen India’s access to strategic and critical minerals vital for technology, renewable energy, and long-term resource security.