Sedimentary rocks dating
The discoveries from Yellowstone park could affect how certain sequences of sedimentary rock are dated, and and also provide a means by which scientists can search for evidence of life on other planets.
Professor Fouke's research was funded by the US National Science Foundation and has been accepted for publication in the Journal of Sedimentary Research.
One of the crucial experiments which the group performed was to draw water from the hot springs vent andmeausre how much calcium carbonate was deposited with the microbes present.
This was then compared with what happened after the microbes were removed from the water.
They found that the rate of calcium precipitation was much higher in intact spring water. The researchers found that the the rate of precipitation sometimes dropped by more than half when the microbes were not present.
Because calcium carbonate is so common, many microbial organisms use it as the main chemical building block of their shells.The findings from Yellowstone park allow researchers to look at the chemistry of different sedimentary rocks and determine the precipitation rate.This in turn will allow them to determine the extent of the contribution of microbes to the rocks being studied.Scientists can now go back to previous records and fingerprint samples which will tell them if microbes were present at the time the rock was formed, and calculate the rate at which the rock formation happened.This can not only be done with sedimentary rocks collected from the Earth's surface but also with rocks from other planets.