Mars’s original crust is more complicated and advanced than previously thought, according to a new study. Scientists have found higher levels of silicon in the Martian crust than they did in Earth’s original surface, suggesting that the two planets’ primordial crusts were similar in composition.
The surface of Mars is composed entirely of basalt due to billions of years of volcanism and surface-flowing lava that cooled. Mars’ crustal past was previously thought to be a simple history because it did not undergo massive surface redoing like the movement of continents on Earth.
However, new research has uncovered regions in Mars’ southern hemisphere that have elevated levels of the chemical element silicon than would be anticipated in a solely basaltic environment. Space rocks colliding with Mars unearthed the silica concentration, excavating material buried many miles below the surface and illuminating a previously unknown history.
The formation of Mars was estimated by scientists to have taken place some 4.5 billion years ago. There are various hypotheses as to the planet’s origins, but no one knows for sure. The formation of Mars has been attributed, in part, to a massive cosmic collision of rocks, which, due to the tremendous energy released, created a completely liquid state, also identified as a magma ocean. According to this theory, the magma ocean progressively cooled, resulting in a crust that is entirely composed of basalt.
The magma ocean may not have covered the entire planet, and it is possible that the first Martian crust had a different origin than the basaltic crust.
Previous studies suggested that the southern hemisphere of Mars was the oldest, so scientists analyzed data from the Mars Reconnaissance Orbiter to confirm this theory. Feldspar, which is typically found in more silicic than basaltic lava flows, was found in abundance at nine different sites, including craters and geological fissures, by the researchers.