The mantle of Mars houses ancient fragments measuring up to 4 km in width from its formation, as revealed by an analysis of seismic data gathered by NASA’s InSight Mission.
The immense collisions during early Mars’ history resulted in a global ocean of magma. Image credit: Vadim Sadovski / Imperial College London.
The planet’s mantle serves as a significant layer, located between the crust and core, preserving vital evidence about its formation and evolution.
In contrast to Earth, where active plate tectonics constantly mix the mantle, Mars functions as a smaller planet with a single plate surface.
This results in considerably less mixing of the Martian mantle, which may retain records of early internal history, providing valuable insights into the formation and evolution of rocky worlds.
Utilizing data from NASA’s InSight Lander, Dr. Constantinos Charalambous from Imperial College London and his colleagues analyzed the seismic signatures of Marsquakes to better understand the composition of the Martian mantle.
They studied eight recorded quakes, including those triggered by the impact of meteorites, discovering that the arrival of high-frequency P-waves is consistently delayed as they traverse deeper regions of the mantle.
The authors suggest that these delays indicate variations in the composition of the mantle stretching over kilometers.
Given that Mars lacks plate tectonics and large-scale recycling processes, these minor irregularities are likely remnants of its formative history.
Investigating the heterogeneity of the Martian mantle implies that it results from an intense and destructive process, reflecting the significant events of the planet’s early history that caused extensive interior disruption and mixed both foreign and crustal materials at a planetary scale.
Furthermore, additional variations might have arisen from the vast ocean of crystallized magma formed during this aftermath.
Rather than being erased, these features were preserved as the Martian crust cooled and mantle convection ceased.
“The seismic signals displayed clear signs of interference while traveling deep within Mars,” Dr. Charalambous noted.
“This coincides with a mantle composed of structures originating from various compositions, representing Mars’ early remnants.”
“What occurred on Mars is that following these initial events, the surface hardened into a stagnant lid.”
“It became isolated from the mantle, entrapping ancient, chaotic features like planetary time capsules.”
“Our observations reveal the distribution of fractals, where energy from violent collisions exceeds an object’s strength.”
“This mirrors the effect seen when glass falls onto a tiled floor, akin to meteorite impacts with a planet. It results in the formation of both large and small fragments.”
“It’s astonishing that we can still detect this distribution today.”
“The Jet Propulsion Research Institute” stated Dr. Mark Panning, a researcher at NASA’s Jet Propulsion Laboratory.
“It’s exhilarating to witness scientists uncovering new findings through the earthquakes we observe!”
The team’s paper was published today in the journal Science.
____
Constantinos Charalambous et al. 2025. Evidence of a highly uneven Mars mantle inferred from earthquake analysis. Science 389 (6763): 899-903; doi: 10.1126/science.adk4292
Source: www.sci.news
