Geobiology and the emergence of terraced architecture during carbonate mineralization

Affiliation(s)PI/CoPIProject PeriodFunded by
DEES Murray, Alison 9/2002 - Present NSF- Biocomplexity: Coupled Biogeochemical Cycles

Keywords: carbonate terraces, Mammoth Hot Springs, Yellowstone National Park, hot springs, thermophiles

 Project Description

Angel Terrace, Mammoth Hot Springs, Yellowstone National Park.
Angel Terrace, Mammoth Hot Springs, Yellowstone National Park.

Carbonate terraces are a pervasive geological form on this planet, and perhaps other planets. This project, led by Bruce Fouke of the University of Illinois, has taken place at Mammoth Hot Springs, Yellowstone National Park. The aim has been to decipher the origins and evolution of carbonate terraces as a function of the biological, chemical and physical regime in hot spring systems. The Murray group has participated in four key aspects of this field-oriented geobiolgy research program. (i) They have described the community structure of bacteria over geological facies transitions and in association with specific crystalline features in the hot spring system. The community structure varies closely with the geological facies model based on chemical/physical boundaries in the system. (ii) An examination into the phylogenetic diversity of archaeal thermophiles in the hot spring vent pool has shown that there are several forms of archaeal life that appear to be abundant there, one that appears to be quite distinct from anything known, and the another that forms a very deep-branching lineage (Korarchaeota) that has no cultivated members. (iii) They have surveyed carbon fixation pathways (and genes involved in them) that are active in photosynthesis in the hot spring system where temperatures exceed 45C. (iv) In fall 2005, they participated in an experimental field study aimed to study carbonate mineralization in hot spring waters with microbes present, with killed microbes, and with the microbes removed by filtration. They are working to the identity of organisms associated with primary mineralization and biofilm development events, while the Illinois groups are working on comparing the quantity and form of minerals formed in each of the three treatments.

DRI News: Seeking the origin of Yellowstone's Travertine Terrace Formation: Are the bugs involved? (2003 Summer newsletter, PDF 1 MB)