Blood Falls is an outflow of an iron oxide-tainted plume of saltwater, flowing from the tongue of the Taylor Glacier onto the ice-covered surface of West Lake Bonney in the Taylor Valley of the McMurdo Dry Valleys in Victoria Land, East Antarctica.
The reddish deposit was found in 1911 by the Australian geologist Griffith Taylor, who first explored the valley that bears his name. The Antarctica pioneers first attributed the red color to red algae, but later it was proven to be due only to iron oxides.Poorly soluble hydrous ferric oxides are deposited at the surface of ice after the ferrous ions present in the unfrozen saltwater are oxidized in contact with atmospheric oxygen. The more soluble ferrous ions initially are dissolved in old seawater trapped in an ancient pocket remaining from the Antarctic Ocean when a fjord was isolated by the glacier in its progression during the Miocene period, some 5 million years ago when the sea level was higher than today.
Chemical and microbial analyses both indicate that a rare subglacial ecosystem of autotrophic bacteria developed that metabolizes sulfate and ferric ions. According to geomicrobiologist Jill Mikucki at the University of Tennessee, water samples from Blood Falls contained at least 17 different types of microbes, and almost no oxygen.An explanation may be that the microbes use sulfate as a catalyst to respire with ferric ions and metabolize the trace levels of organic matter trapped with them. Such a metabolic process had never before been observed in nature.
A puzzling observation is the coexistence of Fe2+ and SO42– ions under anoxic conditions. No sulfide Anions (HS–) are found in the system. This suggests an intricate and poorly understood interaction between the sulfur and the iron biochemical cycles.Chemical and microbial analyses both indicate that a rare subglacial ecosystem of autotrophic bacteria developed that metabolizes sulfate and ferric ions. According to geomicrobiologist Jill Mikucki at the University of Tennessee, water samples from Blood Falls contained at least 17 different types of microbes, and almost no oxygen. An explanation may be that the microbes use sulfate as a catalyst to respire with ferric ions and metabolize the trace levels of organic matter trapped with them. Such a metabolic process had never before been observed in nature. A puzzling observation is the coexistence of Fe2+ and SO42– ions under anoxic conditions. No sulfide anions (HS–) are found in the system. This suggests an intricate and poorly understood interaction between the sulfur and the iron biochemical cycles.
The reddish deposit was found in 1911 by the Australian geologist Griffith Taylor, who first explored the valley that bears his name. The Antarctica pioneers first attributed the red color to red algae, but later it was proven to be due only to iron oxides.Poorly soluble hydrous ferric oxides are deposited at the surface of ice after the ferrous ions present in the unfrozen saltwater are oxidized in contact with atmospheric oxygen. The more soluble ferrous ions initially are dissolved in old seawater trapped in an ancient pocket remaining from the Antarctic Ocean when a fjord was isolated by the glacier in its progression during the Miocene period, some 5 million years ago when the sea level was higher than today.
Chemical and microbial analyses both indicate that a rare subglacial ecosystem of autotrophic bacteria developed that metabolizes sulfate and ferric ions. According to geomicrobiologist Jill Mikucki at the University of Tennessee, water samples from Blood Falls contained at least 17 different types of microbes, and almost no oxygen.An explanation may be that the microbes use sulfate as a catalyst to respire with ferric ions and metabolize the trace levels of organic matter trapped with them. Such a metabolic process had never before been observed in nature.
A puzzling observation is the coexistence of Fe2+ and SO42– ions under anoxic conditions. No sulfide Anions (HS–) are found in the system. This suggests an intricate and poorly understood interaction between the sulfur and the iron biochemical cycles.Chemical and microbial analyses both indicate that a rare subglacial ecosystem of autotrophic bacteria developed that metabolizes sulfate and ferric ions. According to geomicrobiologist Jill Mikucki at the University of Tennessee, water samples from Blood Falls contained at least 17 different types of microbes, and almost no oxygen. An explanation may be that the microbes use sulfate as a catalyst to respire with ferric ions and metabolize the trace levels of organic matter trapped with them. Such a metabolic process had never before been observed in nature. A puzzling observation is the coexistence of Fe2+ and SO42– ions under anoxic conditions. No sulfide anions (HS–) are found in the system. This suggests an intricate and poorly understood interaction between the sulfur and the iron biochemical cycles.
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