Geomicroorganisms and Extreme Environments
Geobiology, Geochemistry, and Microbiology
Penelope Boston, Department of Earth & Environmental Sciences
2005 participants Sarah Statura and Carrie Haglock exploring Spider Cave in southern New Mexico
Project Description:When looking for signs of life on planets with extreme conditions, what form would that life take? Would it be on the surface or in the subsurface? Would it still be "alive" or would it be "fossilized"? And would we recognize it when we found it? When we look for traces of life from earlier Earth epochs, we face some of the same questions. What aspects of microbial communities are reliably preserved in the rock record? This project explores these questions through the investigation of the preservation of life in extreme environments; specifically, the transformation from living microbial communities to distinctive mineralized biosignatures within caves and on rock surfaces.
Caves can host a spectacular array of complex microbial communities. And caves may serve to protect living microorganisms or their remains from hostile surface conditions while possessing an extreme environment of their own. The interaction of microbes and the cave geology and geochemistry produce distinctive living communities and resulting preserved biofabrics, microbial fossils and geochemical signatures. Some of these same processes can be seen on surface rocks, but some processes are different.
To develop the ability to recognize the remnants of microbial life on other planets, such as Mars, and in Earth's early rock record, terrestrial sites with extreme environments can be used as analogs. There are several Mars analogs in the Southwest including the lavatube caves of the El Malpais National Monument in Grants, New Mexico and the Mars Desert Research Station (MDRS) in the desert of south central Utah. Operated by the Mars Society, the MDRS facility is constructed to simulate a future human habitat on Mars and has been in operation for numerous expeditions and simulations since early 2002.
This transformative project will include field and laboratory science that encompass an integrated program of geology, mineralogy, biology, microbiology, planetary science, and observational astronomy. Participants will learn cave/desert safety and wilderness skills. Primary fieldwork will be conducted in one of the lavatubes in the El Malpais National Monument. A potential trip is planned to the Mars Desert Research Station, where participants would conduct field experiments in spacesuit mockups and extravehicular expeditions to nearby geological features and biological sites. Laboratory analyses will be conducted in the Cave and Karst Geomicrobiology laboratory at New Mexico Tech and at associated labs at the University of New Mexico.
Students engaged in this project will:
- use sterile sample collection techniques to obtain microbial samples from the field sites
- document the physical geology of the field sites
- use petrographic, scanning electron microscopy, and x-ray diffraction to characterize the mineralized biosignatures
- use molecular biological methods to characterize communities of microorganisms
