The world’s most famous travertine terraces, in Pamukkale, Turkey

http://www.aksityayincilik.com/turkphto2.htm

Photo by Larry Ulrich

Mammoth hot springs at Yellowstone National Park

Bruce Fouke and Nigel Goldenfeld’s group at the University of Illinois at Urbana-Champaign are studying whether or not microbial metabolic activity plays a significant role in the deposition of these travertine terraces by the degassing of CO2.

Can we use observation of certain geological structures to infer the existence of microbial life? On Earth?

On Mars?

Angel TerraceVent Apron and channel Ponds

Proximal slope

Distal slope

Bacteria

Bruce Fouke and Nigel Goldenfeld biocomplexity group at University of Illinois at Urbana-Champaign

~ 10 cm

Threads of microbes, encrusted with aragonite

Bruce Fouke and Nigel Goldenfeld biocomplexity group at University of Illinois at Urbana-Champaign