GEOL 5903 Seminar - Évelyne Sunatori
27 November 2020
GEOL 5903 Seminar - Évelyne Sunatori
Title: Deep-sea mining: Can it be done sustainably?
Time: 2:30 p.m. - 3:30 p.m.
Presentation via Teams
Abstract:
The world's consumption of minerals has been increasing rapidly over the past decades. To address potential shortages, some companies have been contemplating deep-sea mining, including mining at hydrothermal vents, to exploit these resources. Hydrothermal vents deposit high-grade ores with, in most places, little sediment overlying the seafloor massive sulfides (SMS). Their extraction requires new types of equipment. The average lifespan of a SMS mine is shorter than that of an on-land mine, but with a higher daily capacity. Additional profitable ways of exploiting hydrothermal vents include using some of their biological inhabitants' enzymes for pharmaceutical and cosmetic products, offering underwater tours and making films in the deep-sea. Species living at hydrothermal vents, though not well studied, are known to be very resilient, as they are already surviving numerous minor to major natural and anthropic disturbances, including precipitation of sulfides, fishing, earthquakes and in some places drilling. However, deep-sea mining has been projected to be the most impactful anthropic activity so far, with chemical impacts (e.g., acidity) and physical impacts (e.g., sediment plumes). Various approaches to mitigation of environmental impacts, such as avoidance, minimization and restoration measures, have been assessed and some countries and organizations have made interventions to protect ecosystems at hydrothermal vents. With the lack of testing and knowledge about the vents' ecosystems, however, many scientific uncertainties remain. It is impossible to know exactly what the consequences on the habitat will be, and no legally binding regulations exist to prevent countries from exploiting the deep-sea without restraint. However, with international waters also in ongoing discussion, development of a mining code seems likely.