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- Mars has many volcanoes, just like Earth.<\/strong> Scientists have long thought that these volcanoes, back when they were still active, were relatively simple and disconnected from each other.<\/li>\n
- But a new study of data from the InSight lander mission<\/strong> shows that there were vast, interconnected magma systems below the martian surface.<\/li>\n
- That would mean Mars\u2019 volcanic systems were more earthlike<\/strong> than previously thought, despite the planet not having plate tectonics.<\/li>\n<\/ul>\n
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Huge ancient magma systems on Mars<\/h3>\n
Like Earth, Mars has numerous volcanoes dotting its surface. As far as we know, those volcanoes are now extinct. And scientists have long thought the planet\u2019s volcanic system overall was simpler than Earth\u2019s, since Mars lacks plate tectonics. But now there\u2019s evidence that isn\u2019t quite true.<\/p>\n
Scientists at the University of Oxford in the U.K. said on June 26, 2026, they\u2019ve found evidence that Mars once had enormous, Earth-like magma systems \u2013 interconnected zones of molten rock \u2013 deep beneath its surface.<\/p>\n
Scientists have long categorized Mars as a stagnant lid planet. That means it has one large solid surface, or \u201clid,\u201d instead of the surface being broken into smaller tectonic plates like on Earth. On Earth, plate tectonics drives volcanism, recycling and continent\u2013building.<\/p>\n
But this new study points to huge, interconnected magma systems. They show that Mars\u2019 volcanoes weren\u2019t just simple isolated formations as previously assumed. And they force us to ask \u2026 How did this occur without plate tectonics? <\/p>\n
Lead author Tobermory Mackay-Champion at the University of Oxford said:<\/p>\n
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We\u2019ve traditionally assumed that volcanism on Mars was relatively simple compared to that on Earth. But this discovery suggests the planet could sustain massive, long-lived magmatic systems capable of evolving and reprocessing molten rock throughout the crust. Because these systems are known to generate large metal deposits, Mars may hold significantly more near-surface mineral wealth than previously recognised, boosting its potential for future mining, crewed missions and eventually, permanent settlements.<\/p>\n<\/blockquote>\n
The researchers published their peer-reviewed findings in Nature Astronomy<\/em> on June 26, 2026.<\/p>\n
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NEW: Mars may have been far more Earth-like beneath its surface than scientists once thought ??Oxford researchers have uncovered evidence of vast hidden magma systems that could reshape our understanding of how rocky planets evolve ??<\/p>\n
\u2014 University of Oxford (@ox.ac.uk) 2026-06-26T13:26:02.740122411Z<\/p>\n<\/blockquote>\n
InSight spacecraft data provides clues<\/h3>\n
The researchers made the discovery when analyzing data from NASA\u2019s InSight lander. InSight ended its mission in 2022, but there is still a ton of data to study. The lander recorded seismic waves from marsquakes and meteorite impacts.<\/p>\n
The researchers used the data to investigate an unusual boundary about 15 miles (24 km) below the surface. Scientists knew about the boundary before, but didn\u2019t know what it was. One possibility is that it marked a transition between two different types of rock. To test this, the researchers compared hundreds of different rock compositions with the seismic data.<\/p>\n
![\"3](\"https:\/\/earthsky.org\/upl\/2026\/06\/Mike-Kendall-Tobermory-Mackay-Champion-Professor-Jon-Wade-University-of-Oxford.jpg\")
Mike Kendall, Tobermory-Mackay Champion (lead author) and Jon Wade at the University of Oxford. Image via University of Oxford.<\/figcaption><\/figure>\n Very different rocks below the boundary<\/h3>\n
The results showed that there was indeed a boundary between two types of rock. Below the boundary, the rocks were ultramafic<\/em>, meaning rich in iron and magnesium. But interestingly, the rocks above the boundary were quite different. They were mafic rocks, rich in silica.<\/p>\n
Why is the rock layer below the boundary so different from the layer above? The researchers say that molten rock likely pooled there. Then, it gradually separated into different materials over time. This left behind a residue of dense crystals at the base of the crust. Meanwhile, lighter molten rock moved upwards. This is similar to what happens on Earth beneath volcanic arcs. This is also linked to the formation of continents, although Mars never got to that stage.<\/p>\n
![\"Robotic](\"https:\/\/earthsky.org\/upl\/2021\/01\/InSight-lander-Mars-illustration-cutaway-view-e1611091493964.jpg\")
View larger. | Illustration depicting NASA\u2019s InSight lander on Mars, with a cutaway view of the subsurface. Image via PGP\/ Nicolas Sarter\/ Jet Propulsion Laboratory\/ NASA.<\/figcaption><\/figure>\n Vast magma layer across the northern hemisphere<\/h3>\n
The researchers say this magma layer was vast, spanning hundreds of miles sideways beneath the surface. That means that instead of Mars\u2019 volcanoes being isolated, they were actually interconnected by these sprawling magma systems. On Earth, this is known as transcrustal magmatism. Until now, scientists only knew of it occurring on one planet: Earth.<\/p>\n
But if it happened on Mars too, that raises questions about how rocky planets form and if they can be habitable. Co-author Jon Wade at the University of Oxford said:<\/p>\n
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One of the big questions in planetary science is whether Earth is unique. If Mars could develop this kind of complex crust without plate tectonics, then maybe the conditions needed for habitability can emerge on more planets than we realised, including those previously dismissed based on size or their apparent lack of tectonic activity.<\/p>\n<\/blockquote>\n
In 2024, scientists reported evidence for magma possibly still existing beneath Olympus Mons, the largest volcano on Mars. If so, it would mean that there is still some residual tectonic and volcanic activity below the surface today. Mars might still be alive, at least geologically!<\/p>\n
Bottom line: Scientists have found evidence of enormous ancient magma systems on Mars. They show that Mars\u2019 volcanic systems were once more complex than first thought.<\/p>\n
Source: Seismic evidence for a melt-depleted lower crust and transcrustal magmatism on Mars<\/p>\n
Via University of Oxford<\/p>\n
Read more:<\/p>\n
Ancient volcanoes on Mars were diverse<\/p>\n
The most recent volcanoes on Mars were surprisingly active<\/p>\n
34 dust devils on Mars in 1 shot! Can you spot them all?<\/p>\n
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\n - But a new study of data from the InSight lander mission<\/strong> shows that there were vast, interconnected magma systems below the martian surface.<\/li>\n