Geomicrobiology Group
Research Projects - Modern Extremophiles
Microbial preservation in evaporitic aeolian settings; White Sands National Monument (New Mexico)
The White Sands National Monument contains one of the largest known gypsum dune fields and holds active playas, a playa lake and Pleistocene lake beds, which allows for an excellent comparison of these different (hyper)saline evaporitic habitats. Comparison of environmental physicochemical conditions and molecular biology are used to determine the characteristics of microbial habitats and communities and to decipher changes these ecosystems go through during early diagenetic processes.
On Mars, the presence of sulfate rich dune deposits has been identified for dunes in North Polar Region, while the presence of and playa/playa lake deposits has been inferred for the deposits discovered by the Opportunity rover at Meridiani Planum and for sulfate rich deposits of Gale crater, the landing site of Curiosity rover. The study of terrestrial analogue site, such as WSNM, provides an analogue system to explore and characterize the proposed habitable zones on Mars and their potential biosignatures.
Probing deep biosphere; Deep drilling into an active volcano, Campi Flegrei (Italy)
Deep drilling at Campi Flegrei area near Naples (Italy) provides a rare opportunity to study deep biosphere and carbon cycling related to volcanic processes at depths spanning from the surface to the magma chamber. The Campi Flegrei Deep Drilling Project (CFDDP) is a joined project of Istituto Nazionale di Geofisica e Vulcanologia (INGV), Osservatorio Vesuviano and the International Continental Drilling Project (ICDP). The drilling project is carried out in two steps. The first step is drilling of a pilot hole, which has been successfully finalized in December 2012. The aim of this step was to drill to 500m depth to plan for successful deep drilling. We have participated in pilot drilling and have collected core samples from 480 and 504 m depth. The later step includes the drilling of a 3.8 km deep borehole.
We will characterize different pools of carbon in this system. Surface sources of organic carbon have been studied through a number of studies, including extremophilic microbial communities from the surface hydrothermal vents; however, the insight into subterranean distribution of the ecosystem is completely unknown.
Jotun Spring, Svalbard (Norway)
Jotun geothermal spring from Spitsbergen Island (79°27’N, 13°17’E) is dominated by travertine gravel, which has formed a terrace around the spring’s source area and down the slope/stream. This spring and associated terraces are dominated by microbial biomass, probably because the shifting environment of the spring offers little opportunity for higher organisms to thrive. We studied two transects to illustrate two different environmental gradients: (1) from the spring source to the end of the stream, which has a continuous source of nutrients, is fully aquatic, and rich in microbial mass; (2) along the gravely travertine plateau, from the spring source to the plateau edge with limited nutrient access, primarily travertine gravel with no visible microbial biomass at the surface. A combination of environmental physicochemical conditions, stable isotopes, and molecular biology were used to determine the characteristics of environmental gradients and communities and to decipher nodes of nitrogen and carbon cycles.