The Possibility of Granite on Mars

Just last year, NASA researchers found large amounts of new minerals on Mars. The evidence of the minerals in ancient volcanos on the Red Planet was a groundbreaking discovery by NASA’s Mars Curiosity rover. The Mars Curiosity rover detected signs of light colored rock as it explored. Our very own astronomy team at the Georgia Institute of Technology got in on the study of the findings.

For many years, Mars was believed to be fairly homogenous when it comes to its makeup. It primarily consists of basalt, a dark lava rock rich in iron and magnesium found on Earth’s ocean floor and the Hawaiian Islands. Ultimately, the makeup of Mars was considered to be far less complex than the composition of Earth. After analyzing the discovery made by the Mars Curiosity rover, the Georgia Tech team determined the light colored rock contained feldspar, a group of rock-forming minerals that make up about 60% of Earth’s crust, and possibly quartz. Interestingly, in the areas where feldspar was detected, basalt was almost completely absent.  Thus, Mars may be a far more complex planet than we believed.

PHOTO CREDIT: NASA. Here in a volcanic caldera, bright magenta outcrops have a distinctive feldspar-rich composition.

So, what does this mean about the possibility of granite on Mars? Feldspar and quartz, along with mica and other amphibole minerals, are the primary components of granite. By definition, granite consists of up to 65% feldspar and at least 20% quartz by volume. On Earth, granite is abundant and frequently found in tectonically active regions, so it makes sense that traces of feldspar were located near volcanic regions on Mars. The analysis of the region on Mars in combination with generated computer simulations shows that the intricate process by which granite is formed could occur inside an active volcano on Mars over a long period of time.

Evidence shows that the volcanos on Mars were likely active for billions of years and could result in the generation of granite. Most volcanos on Mars are blanketed with dust, but the particular volcano where evidence of feldspar was detected, the volcano Syrtis Major, is dust free due to being sand blasted by powerful, fast-moving sand dunes on the planet. According to the lead author of the study “Prolonged magmatic activity on Mars inferred from the detection of felsic rocks” and astronomer at the Georgia Institute of Technology, Dr. James Wray, if Syrtis Major is indicative of other volcanic regions on Mars, a percent or two or three of the planet is comprised of these granite rocks, plus another ten percent or so with a similar composition to granite.

*The full study of these findings is published in the journal Nature Geoscience.