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A Japanese-led international research team has found evidence that could change the way scientists think about how continents are formed. By looking at rocks from a volcano in the South Pacific researchers discovered support for a model where andesitic magma can form directly from the Earths mantle under thin oceanic crust.
The study looked at Hunga volcano in Tonga the place of the Hunga Tonga-Hunga Ha’apai eruption in January 2022. Scientists from the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) GNS Science in New Zealand and the National Institute of Advanced Industrial Science and Technology (AIST) studied rock samples gathered from the volcanos ocean floor. The results were shared in Scientific Reports.
The findings might be important for more than geology. They give knowledge about volcanic dangers, underwater monitoring and ways to prevent disasters. Issues that are very important for Japan.
Hunga Volcano Provides New Geological Evidence
Hunga volcano became a focus for scientists after its huge 2022 eruption. The volcano has features similar to Nishinoshima, an island in Japans Ogasawara Islands that has also been used to study how new continental material can be created.
Scientists took lava and magnesian andesite lava directly from the underwater side of Hunga volcano. According to the research group this was the time such rock samples had been taken from the volcano after the eruption.
Analysis showed signs of two main magmas. Basaltic and andesitic. Coming from different depths in the mantle. The researchers think that when these magmas mixed quickly at depths it helped make the 2022 eruption very explosive.
This discovery adds proof for what researchers call the “Nishinoshima model.”
A New Perspective on How Continents Form
The way people think about how continents form is that basaltic magma is made first then the rocks melt again to make andesite.
The Nishinoshima model has an idea.
With thin oceanic crust andesitic magma can be created directly from the mantle. Over long time periods this material can build up. Help make continents.
The discovery of andesitic magma at Hunga volcano is important because Hunga is thousands of kilometers away from Nishinoshima. Finding the kind of geological process in a different volcanic area shows that this way of forming might not be special to Japan. Scientists say it could be a general process in how continents form.
This would make the research important not for Japanese geology but also for wider studies, about Earths history.
Implications for Volcanic Disaster Prevention
The research also has an immediate application.
The researchers found similarities between the magma-mixing process at Hunga and the observations from Nishinoshimas 2020 eruption. The magma-mixing at Hunga was comparable to the magma-mixing seen at Nishinoshima. These similarities suggest that interactions between different magma sources could give useful information for understanding explosive submarine eruptions.
For Japan this is particularly relevant. Japan sits along the Pacific Ring of Fire and Japan has active volcanoes, including submarine volcanic systems.
Improving understanding of how magma moves and mixes beneath volcanoes could help scientists identify conditions associated with explosive volcanic eruptions. That knowledge could eventually help build monitoring systems and disaster-prevention planning.
However the study does not mean that researchers can now accurately predict eruptions. Volcanic systems remain complex and further observations and modeling will be necessary.
Technology Is Central to Modern Earth Science
The study also shows how modern geological research increasingly depends on technology.
Collecting samples from volcanoes requires specialized vessels remotely operated or other marine survey equipment, geological instruments and detailed laboratory analysis. Researchers then combine samples from underwater volcanoes with geochemical and petrological data to reconstruct processes occurring deep beneath the Earths surface.
For Japans technology sector this creates opportunities in robotics, sensors, autonomous underwater systems, geospatial analysis and scientific computing.
JAMSTECs involvement is particularly significant because Japan has developed expertise in deep-sea exploration and marine research. Continued investment in these capabilities can support both science and practical applications such as disaster monitoring and environmental observation.
Opportunities for Japan’s Deep-Tech Industry
The research illustrates how scientific discoveries can create demand for technologies beyond traditional laboratory equipment.
Sophisticated volcanic monitoring could require networks of underwater sensors capable of collecting information about temperature, pressure, seismic activity and chemical changes. Autonomous systems could expand the areas that researchers can monitor while reducing the need for human operation.
Data-analysis technologies could help researchers combine observations from sources and identify changes in complex volcanic systems.
These applications align with Japans strengths, in robotics, sensing, marine engineering and advanced materials.
A Broader Lesson for Japan
The Hunga research shows how important it is to invest in science over a long time. A study that started with the goal of learning about a volcanic eruption has given information that might change ways people think about how continents were created.
こちらもお読みください： 日本の研究、南大西洋の海水温上昇と南極の積雪を関連づける
For Japan the research also shows how science and technology are connected. The ability to explore the ocean can help learn about the Earths structure and the same tools can help prepare for disasters and keep an eye on the environment.
The results do not change the story of how the Earth was formed away but they make the Nishinoshima model seem more likely to be a common process in geology.
As scientists keep looking into systems all over the world Japans mix of knowledge in Earth sciences, ocean technology and research on how to prevent disasters could help the country take a key part, in learning about where continents came from and the dangers of active volcanoes.
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