How far does bacteria and other microscope forms of life exist in the Earth?

Question

does it exist in the crust and the mantle,ect.

Answer 1

depend on their lifespan and the atmosphere.

Answer 2

Deepest they live I believe is microbes in subterranean lakes.

Answer 3

Bacteria and archea live underground, they eat hydrogen, methane and carbon dioxide. The weight of life underground may equal the weight of life above ground. The hardy microorganisms can survive temperatures of up to 110 to 120 degrees Celsius, and since the temperatures underground increases by 15 to 20 degrees Celsius per km, life could exist up to 8 km underground.

Answer 4

what do you mean

Answer 5

Microbial life has been discovered 4.2 kilometers deep in Alaska and 5.2 kilometers deep in Sweden. Methanophile organisms have been known for some time, and recently it was found that microbial life in Yellowstone National Park is based on hydrogen metabolism. Other deep and hot extremophile organisms continue to be discovered. Proponents of abiogenic petroleum origin contend that deep microbial life is responsible for the biomarkers that are generally cited as evidence of biogenic origin. U.S. Geological Survey (USGS) scientist Frank Chapelle and his colleagues from the USGS and the University of Massachusetts have discovered a potential analog for life on other planets. A community of Archaea bacteria is thriving deep in the subsurface source of a hot spring in Idaho. Geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. This is the first documented case of a microbial community completely dominated by Archaea.

http://en.wikipedia.org/wiki/Abiogenic_p...

At first, the finding of bacteria in cores from as much as kilometers deep was discounted - explained as contamination by surface bacteria. But careful, sterile handling of core samples - for example, kept in chambers of inert gas and carefully guarded against any exposure to the surface environment - has shown that bacteria and even higher multicellular protozoa (feeding on the bacteria) live to great depths in the interior of the Earth.  Many of the bacteria species consume organic material that has been resorbed into the Earth's interior: this material is, for example, the source of our oil and gas reserves. These species metabolize with oxygen and are thus not so different, in this metabolic-functional sense, from surface bacteria.

http://www.resa.net/nasa/otherextreme.ht...

The super deep well SG-3, 12 262 m deep in the Pechenga-Zapolyarny area, Kola Peninsula, Russia, is currently the deepest drilled hole in the world. One of many important reasons for drilling this borehole was to see how deep a borehole could be drilled. The prospect of drilling a super deep borehole gets more difficult with increasing depth, and success depends on the geological formation drilled, the quality of equipment used and the skill of the drilling personnel. In addition, the drill string may get stuck in a layer with bad borehole stability, and this is always a major uncertainty in deep drilling projects. The German continental deep drilling program (KTB) drilled several deep Cretaceous-Tertiary boundary boreholes into the crystalline rock of the Bavarian Black Forest (Schwartzwald) basement in Central Europe. The deepest of the six wells drilled is 9100 m and it reached an in situ temperature of 265 C at that depth. One of these KTB wells was searched for hyperthermophiles at 4100 m depth. Cultivable microorganisms could not be demonstrated, possibly because of a too high temperature for life of the sampled fluids, which was 118 C. So far, the highest culturing temperature for hyperthermophiles has not exceeded 113 C. Another very deep borehole was drilled in Gravenberg, Sweden in the search for deep earth gases. It reached 6800 m and here thermophilic bacteria were successfully enriched and isolated from a depth of 5278 m where the temperature was 65 - 75 C.

The borehole windows into super deep environments are still very few, and none has been drilled with microbiology as its major aim. Boreholes drilled with the purpose of exploring microbial life are seldom deeper than 1000 m. Depth alone is not limiting for how deep life extend as can be understood comparing the lifeless German 4100 m deep KTB borehole and the microbially populated Swedish 5278 m deep Gravenberg borehole. Instead, a too high temperature for life sets the ultimate limit for how deep life can penetrate into our planet. This temperature is reached at very different depths, from the seafloor surface at marine hot springs to ten kilometer or more in massive sedimentary rock formations. The absolute majority of boreholes explored for microbial life do not reach such depths because the drilling cost for a borehole increases with depth, which, together with increasing technical challenges limit the number of super deep boreholes to very few. In addition to drilling, tunnels and mines can be used for the exploration of intra-terrestrials. The exploration of intra-terrestrial life is consequently, in parallel to the exploration of life on other planets, strongly dependent on sophisticated technological equipment and skills. The exploration of the (super) deep intra-terrestrial biosphere has merely begun.  (article too long to post in entirety)

http://www.gmm.gu.se/groups/pedersen/pop...