Researchers from the Georgia Institute of Technology have discovered stronger evidence of granite on Mars. In addition, they have come up with a new theory for how the granite could have developed on the Red Planet. The results of the study imply that Mars is a much more geologically complex planet than previously thought.

Sizable quantities of a mineral known to exist in granite, called feldspar, were discovered in an old Martian volcano. Plus, minerals that are commonplace in basalts that are rich in iron and magnesium, universal on the Red Planet, are almost completely gone at this spot. The location of the feldspar also helps scientists determine how granite could have developed on Mars. Granite is often discovered on Earth in tectonically active regions like subduction zones. Scientists believe that unabating magmatic activity on Mars can also create these compositions on big scales.

For many years the Red Planet was thought to be geologically simple, made primarily of one type of rock, as opposed to our planet, which is geologically diverse. The rocks that blanket most of the Red Planet’s surface are dark-colored volcanic rocks, known as basalt, a kind of rock also present throughout the Hawaiian islands.

Curiosity, however, found soils with a structure similar to granite. Scientist didn’t know what to think about the finding because it was restricted to one spot on the Red Planet.

The researchers utilized remote sensing methods with infrared spectroscopy to explore a huge volcano on the Red Planet that was active for billions of years. The volcano is dust-free because it’s being sand-blasted by some of the quickest-moving sand dunes on the planet. Inside the old Martian volcano, the researchers discovered rich deposits of feldspar.

The spot of the feldspar and dearth of dark minerals inside the old volcano offers an explanation for how granite developed on the Red Planet. While the magma unhurriedly cools in the subsurface, low density melt detaches from dense crystals in a process known as fractionation. The cycle repeats for millennia until granite is developed. According to computer simulations, this process could take place inside of a volcano that is active for an extremely long period of time.

Interestingly, another study described in the same edition of the journal Nature Geoscience by another research team details a different comprehension of the feldspar-rich evidence on the Red Planet. Researchers from the European Southern Observatory and the University of Parks discovered a similar signature in a different location on Mars, but compare the rocks to anorthosite, which is commonplace on the moon.

Regardless, the results imply that Mars is more geologically diverse than previously thought.