Volcanoes may look like simple mountains that erupted once and then fell silent, but in reality they are often the surface expression of complex processes happening deep underground.
Magma can move, collect, cool, and change over long periods before reaching the surface. Scientists usually study the rocks and minerals left behind by eruptions to understand what was happening beneath.
Now, new research shows that this hidden complexity also applies to volcanoes on Mars.
A recent study published in the journal Geology reveals that some of Mars’ youngest volcanic systems were not formed by single, brief eruptions as once believed.
Instead, they developed through long-lasting underground activity, with magma systems that changed over time.
High-resolution images and mineral data collected by orbiting spacecraft allowed scientists to take a closer look at these volcanic features without ever setting foot on the planet.
An international team of researchers examined a volcanic region located south of Pavonis Mons, one of the giant volcanoes in Mars’ Tharsis region. By combining detailed mapping of the surface with information about the minerals present in the rocks, they reconstructed the history of the volcano in remarkable detail. Their findings show that the volcano went through multiple stages of activity rather than a single eruption.
Early in its history, lava flowed out through long cracks in the ground, a process known as fissure eruptions. Later, activity shifted to more concentrated vents that built cone-shaped structures, similar to small volcanic mountains on Earth. Although these different features look unrelated on the surface, the study found they were all fed by the same underground magma system.
The minerals found in the lava flows provided key clues. Each phase of eruption left behind rocks with slightly different mineral compositions.
These differences suggest that the magma itself was evolving over time, possibly because it came from different depths or remained stored underground for varying lengths of time before erupting. In other words, the volcano’s underground plumbing system was changing as the planet’s interior slowly cooled and shifted.
Because scientists cannot yet collect rock samples directly from Mars, studies like this rely on advanced instruments aboard orbiting spacecraft. These tools can detect subtle variations in color and composition that reveal what minerals are present, helping researchers piece together the planet’s geological history from afar.
The findings offer new insight into how Mars has changed over time and suggest that volcanic activity on the planet may have lasted longer and been more dynamic than previously thought.
Understanding these processes also helps scientists compare Mars with Earth and other rocky planets, shedding light on how planets evolve and whether they might once have supported conditions suitable for life.
