Microbial Life in Extreme Environments Thermophiles Slide 1:Title slide. Slide 2:Examples of hot zones:Yellowstone National Park hot spring,hydrothermal vent, compost pile,and the deep Earth Slide 3:movie clip from the Mid-Cayman Rise Hydrothermal vent system.This is the deepest hydrothermal vent system known at about 5 km depth.Perhaps a window into deep subsurface microbial life? Slide 4:Image of Earth's tectonic plates that connect to one another in various ways (convergent-one moves under another,divergent-they both move away from one another,and transform-they move alongside one another). Slide 5:Mantle convection cells move the plates around.In the mantle hot material rises towards the crust.When it reaches the base of the crust it cools and sinks back down through the mantle This slow but incessant movement in the mantle causes the rigid tectonic plates to move (float) around the earth surface (at an equally slow rate). Slide 6:Heat rising from deep within the earth produces fumaroles and solfataras.Fumaroles are a geothermally heated opening in the Earth where steam and hot gases are expelled. Solfataras(Italian name)are a relatively cool type of fumarole(between 100C and 300C)that gives off hydrogen sulfide that reacts with the oxygen in the air to produce sulfur deposits. Slide 7:There are two basic types of hydrothermal vents.They come in very different chemistries.Black smokers produce lots of sulfur minerals that make dark plume.Their chimneys are made of calcium sulfate and metal sulfides.White smokers produce barium, calcium and silicon precipitates which form a white plume.Their chimneys are made of calcium carbonate.Lost City in the Mid-Atlantic Ridge produces white smokers.Reactions between seawater and upper mantle peridotite produce methane-and hydrogen-rich fluids that are highly alkaline(pH 9 to 11),with temperatures ranging from <40 to 90C. Slide 8:Some additional notable features of hydrothermal vents.The first vent paper:Lonsdale, P.(1977)."Clustering of suspension-feeding macrobenthos near abyssal hydrothermal vents at oceanic spreading centers".Deep Sea Research 24(9):857.No one on this geology cruise expected to discover new species,but they did!Supercritical fluids refer to a phase of water having both gas and liquid properties.They are formed at high temperature and high pressure, such as within certain hydrothermal vents.In 1992 a paper was published called The Deep Hot Biosphere by Thomas Gold.It suggested that life could extend far below hydrothermal vents. This hypothesis is still of great interest today.Mining vents?They contain polymetallic sulfides. Some of the metals are quite valuable and some companies would like to mine them.Microbial Life in Extreme Environments Thermophiles Slide 1: Title slide. Slide 2: Examples of hot zones: Yellowstone National Park hot spring, hydrothermal vent, compost pile, and the deep Earth. Slide 3: movie clip from the Mid-Cayman Rise Hydrothermal vent system. This is the deepest hydrothermal vent system known at about 5 km depth. Perhaps a window into deep subsurface microbial life? Slide 4: Image of Earth’s tectonic plates that connect to one another in various ways (convergent – one moves under another, divergent – they both move away from one another, and transform – they move alongside one another). Slide 5: Mantle convection cells move the plates around. In the mantle hot material rises towards the crust. When it reaches the base of the crust it cools and sinks back down through the mantle. This slow but incessant movement in the mantle causes the rigid tectonic plates to move (float) around the earth surface (at an equally slow rate). Slide 6: Heat rising from deep within the earth produces fumaroles and solfataras. Fumaroles are a geothermally heated opening in the Earth where steam and hot gases are expelled. Solfataras (Italian name) are a relatively cool type of fumarole (between 100°C and 300°C) that gives off hydrogen sulfide that reacts with the oxygen in the air to produce sulfur deposits. Slide 7: There are two basic types of hydrothermal vents. They come in very different chemistries. Black smokers produce lots of sulfur minerals that make dark plume. Their chimneys are made of calcium sulfate and metal sulfides. White smokers produce barium, calcium and silicon precipitates which form a white plume. Their chimneys are made of calcium carbonate. Lost City in the Mid-Atlantic Ridge produces white smokers. Reactions between seawater and upper mantle peridotite produce methane- and hydrogen-rich fluids that are highly alkaline (pH 9 to 11), with temperatures ranging from <40° to 90°C. Slide 8: Some additional notable features of hydrothermal vents. The first vent paper: Lonsdale, P. (1977). "Clustering of suspension-feeding macrobenthos near abyssal hydrothermal vents at oceanic spreading centers". Deep Sea Research 24 (9): 857. No one on this geology cruise expected to discover new species, but they did! Supercritical fluids refer to a phase of water having both gas and liquid properties. They are formed at high temperature and high pressure, such as within certain hydrothermal vents. In 1992 a paper was published called The Deep Hot Biosphere by Thomas Gold. It suggested that life could extend far below hydrothermal vents. This hypothesis is still of great interest today. Mining vents? They contain polymetallic sulfides. Some of the metals are quite valuable and some companies would like to mine them