SIUC Planetary Geology
The geology program at SIU has recently developed a planetary geology research group – specifically the study of Mars. Drs. Filiberto, Lefticariu, and Potter-McIntyre, along with their students, focus research on the study of the origin of Martian rocks, the fluids that alter them, and the potential for habitability. The research is done by studying Martian meteorites and terrestrial analogs, and comparing these with in situ studies of the Martian crust from NASA rover missions.
Martian Meteorites: Martian meteorites are pieces of the Martian crust that have been blasted off the surface, flown through space, and landed on the Earth. These rocks give us the ability to use detailed laboratory studies to investigate their petrology, mineralogy, and geochemistry and make comprehensive studies of Mars. Dr Filiberto, along with his students, has been investigating what clues these rocks can tell us about the interior water content of Mars. Degassing of water-rich magmas on Earth provide a friendly environment for life. However, Martian magmas were significantly drier than their terrestrial counterparts, suggesting that degassing of Martian magmas may not have provided such a habitable environment.
Terrestrial Analog Research: One of the frontiers in sedimentary geology is the study of terrestrial analogs for understanding extraterrestrial processes. The sedimentary geology group at SIU, led by Dr. Potter-McIntyre, focuses on analogs for sedimentary environments on Mars that were likely extreme (by Earth standards) such as hypersaline lacustrine environments that existed on the Colorado Plateau during the Jurassic and are now preserved in the rock record. These environments show many similarities to rocks that were deposited in Gale crater on Mars that are currently being investigated by the rover, Curiosity. Study of these terrestrial rocks shed light on both terrestrial and martian depositional environments, sedimentary processes, and fluid/rock interactions that are preserved in the rock record.
Acidic Environments: As scientists look for life outside Earth, candidate planetary settings with extreme conditions are often considered. On Mars, unique surface topographies and mineralogical assemblages that are indicative of past extreme acidic conditions occur in many regions across the planet suggesting that acidic alteration may have been a key process at local and regional scales throughout Martian geologic history. On Earth, acidic environments are often associated with abandoned mine lands where oxidation of pyrite and other materials produces waters that are acidic and loaded with poisonous metals. Even though these acid, heavy-metal-containing waters are toxic to most life forms, communities of acid-loving microorganisms not only survive but they also thieve in such acidic waters. Our research group, led by Dr. Liliana Lefticariu, has been involved in studying the mineralogy, geochemistry, and biology of acidic environments on Earth with the ultimate goal of identifying habitability factors for extreme acidic environments on Mars.