After years of speculation, scientists from the University of Southampton in the United Kingdom have solved a long-standing mystery surrounding the discovery of diamonds from the Earth’s surface.
The breakthrough reveals that these valuable gems are ejected to the surface during kimberlite eruptions, described as a “fountain of diamonds”.
Kimberlite eruptions involve a mixture of water, rock, carbon dioxide and basic kimberlite materials, including diamonds, creating a massive wave that can reach speeds of up to 83 miles per hour.
Research points to major geological events, specifically the separation of tectonic plates, as the trigger for these eruptions.
The investigation suggests that as the tectonic plates shift, rocks in the upper mantle and lower crust mix and flow against each other, triggering these diamond-rich eruptions.
Analysis of the data shows that these “diamond fountains” occur at intervals of 22 to 30 million years.
Earth and climate science professor Thomas Gernon expressed the team’s aim to identify new, untapped diamond deposits.
He emphasized the significant time these diamonds spend at the base of the continents waiting for the stimulus that will lead to powerful and explosive eruptions.
The findings shed light on why these eruptions are periodic, in line with major geological events such as the breakup of the supercontinent Gondwana about 180 million years ago.
This division eventually gave rise to continents such as South America and Africa, with diamond eruptions 25 million years later.
Professor Gernon highlighted the orchestrated physical process involved and suggested that the phenomenon could extend beyond the kimberlites and affect various Earth system processes.
The research used statistical analysis and machine learning to investigate the link between continental breakup and kimberlite volcanism.
Senior Research Fellow Dr Thea Hincks highlighted the team’s geospatial analysis, which revealed a gradual migration of kimberlite eruptions from continental margins to the interior over time, with consistent rates across continents.
The breakthrough not only demystifies the origin of diamonds, but also provides valuable insights into the Earth’s geological processes and their influence on the rare gem’s journey to the surface.
