Why in news?
In September 2025 the Ministry of Earth Sciences signed a 15‑year contract with the International Seabed Authority (ISA) for exclusive rights to explore polymetallic sulphides (PMS) in a 10,000 square‑kilometre area of the Carlsberg Ridge in the Indian Ocean. This is India’s second PMS exploration contract, making it the first country to hold two such contracts.
What are polymetallic sulphides?
Polymetallic sulphides are deposits of metal‑rich minerals formed by hot hydrothermal fluids that emerge from cracks in the ocean floor. As the fluids mix with cold seawater they precipitate metals like iron, copper, zinc, silver, gold and platinum, forming chimney‑like structures called hydrothermal vents. These metals are valuable for renewable energy technologies, electronics and alloys.
About the Carlsberg Ridge
- Location: The Carlsberg Ridge is a mid‑oceanic ridge — a divergent plate boundary — in the Indian Ocean. It extends from the triple junction of the African, Indian and Australian plates northwest to the Gulf of Aden.
- Geography: The ridge separates the Arabian Sea to the northeast from the Somali Basin to the southwest. Its peaks rise about 2,100 metres above the surrounding seafloor but remain 1,800–3,600 metres below the sea surface.
- Seismic activity: As part of the larger Central Indian Ridge, the Carlsberg Ridge is prone to earthquakes and hosts numerous hydrothermal vents that support unique deep‑sea ecosystems.
Significance of the contract
- Strategic minerals: Securing rights to explore PMS ensures a potential future supply of critical metals required for solar panels, batteries and electronics. Diversifying sources reduces dependence on imported minerals.
- Leadership in deep‑sea research: By holding two contracts India now has the largest exploration area for PMS under the ISA regime. The contract strengthens India’s presence in the international seabed and underscores its commitment to the “blue economy.”
- Deep Ocean Mission: The exploration aligns with India’s Deep Ocean Mission, which aims to develop technology for seabed mining, underwater robotics and environmental protection.
- Environmental considerations: Exploration will be accompanied by studies to understand deep‑sea ecosystems and mitigate potential harm. The ISA requires contractors to balance resource utilisation with protection of marine biodiversity.
While commercial mining is still years away, the contract represents a step towards tapping seabed minerals in an era of energy transition. It highlights the need for responsible exploration, technology development and international cooperation.