Researchers have successfully drilled the deepest-ever sample of rocks from Earth’s mantle, reaching a depth of 0.7 miles (1.2 kilometers) in the Mid-Atlantic Ridge. This location is known for its abundance of hydrothermal vents, where interactions between mantle rocks and seawater create essential chemicals for life. Previous attempts to drill into mantle rocks in the deep sea fell short, only reaching depths of 659 feet (201 meters), limiting the exploration for organisms like heat-loving bacteria that may exist further down.
Gordon Southam, a geomicrobiologist at the University of Queensland and co-author of the study, highlighted the importance of this expedition in understanding the origins of life and the potential for life beyond Earth. The core sample obtained during the drilling will provide valuable insights into the movement of the mantle and the different compositions found within it.
Johan Lissenberg, a geochemist at the University of Cardiff and lead author of the study, emphasized that the rock core can reveal the various “flavors” of the mantle, indicating different rock compositions resulting from the recycling of tectonic plates. By analyzing these samples, researchers can reconstruct how the mantle melts and migrates towards the surface.
The International Ocean Discovery Program conducted the drilling in 2023 aboard the JOIDES Resolution research vessel. The team successfully extracted intact sections of up to 16.4 feet (5 meters) from the hole, providing a continuous record of over 70% of the 0.7-mile core. Despite the fragile nature of mantle rock, the drilling process went smoothly, exceeding the team’s expectations.
William Brazelton, a microbiologist at the University of Utah and study co-author, noted the abundance of samples collected during the expedition, allowing for a comprehensive analysis of microbial diversity and activity at different depths and temperatures. The team worked tirelessly, smashing rocks with sledgehammers around the clock to gather as much data as possible.
Overall, this groundbreaking expedition has the potential to unlock the secrets of Earth’s mantle and shed light on the complex processes that shape our planet. The discoveries made during this mission could have far-reaching implications for our understanding of life on Earth and the possibilities of life beyond our planet.