The Zonation and Structuring of Siliceous Sinter around Hot Springs, Yellowstone National Park, and the Role of Thermophilic Bacteria in Its Deposition

Mapping vent to distal-apron hot spring paleo-flow pathways using siliceous sinter architecture

“…These silicified microbes produce distinctive macro-textures that relate to temperature-pH gradients and the hydrodynamics of hot spring environments. There are many documented reports of biologically influenced sinter textures that relate to hot spring environmental conditions (Weed, 1889a,b;Walter, 1976;Farmer and Des Marais, 1994;Cady and Farmer, 1996;Hinman and Lindstrom, 1996;Konhauser and Ferris, 1996;Jones et al, 1997Jones et al, , 1998Jones et al, , 2002Campbell et al, 2001Campbell et al, , 2004Konhauser et al, 2001;Lowe et al, 2001;Chafetz, 2002, 2003b;. Silicified microbes can constitute up to half of a sinter deposit (Bartley, 1996;Cady and Farmer, 1996;Konhauser et al, 2001).…”

“…The filamentous cyanobacterium Leptolyngbya (previously called Phormidium) thrives in mid-temperature alkali chloride waters (cf. Walter, 1976;Lowe et al, 2001) and consists of microbes with finely filamentous, <5 m exterior diameters ( Fig. 5c; Hinman and Lindstrom, 1996;Campbell et al, 2001;.…”

“…5b reveals a pool surrounded by a rim of mid-temperature, orange, microbial mat located at Yellowstone National Park, U.S.A. Mid-temperature microbial mats are inhabited by thin, sheathed filamentous cyanobacteria (cf. Walter, 1976;Cady and Farmer, 1996;Lowe et al, 2001). The filamentous cyanobacterium Leptolyngbya (previously called Phormidium) thrives in mid-temperature alkali chloride waters (cf.…”

“…Silicified microbes can constitute up to half of a sinter deposit (Bartley, 1996;Cady and Farmer, 1996;Konhauser et al, 2001). The silicification of all components results in the preservation of a variety of textural fabrics where each texture reflects specific environmental conditions, such as water temperature and/or flow-rate (Cassie, 1989;Merz, 1992;Cady and Farmer, 1996;Walter et al, 1996;Jones et al, 1997Jones et al, , 2001Lowe et al, 2001;Guidry and Chafetz, 2003a,c;. Therefore, sinters provide valuable records of paleo-biologic, paleo-hydrologic, and paleo-environmental conditions in hydrothermal settings.…”

“…These thermophilic filamentous microbial and/or eukaryotic communities are the best indicators of alkali chloride hot spring water temperature, as distinct microbial communities exist within specific temperature ranges. Measurement of filament exterior sheath and internal trichome diameters have been used as indicators of approximate temperature gradients for cyanobacteria, and represent a range of locations across a sinter deposit from vent to distal-apron slope (Walter, 1976;Cassie, 1989;Cassie and Cooper, 1989;Farmer and Des Marais, 1994;Cady and Farmer, 1996;Jones et al, 1998;Lowe et al, 2001;Guidry and Chafetz, 2003a;Jones et al, 2004). As silica precipitates the microbial mats become coated with opal-A silica.…”