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Sedimentary dating

sedimentary dating-84

Radioactive elements were incorporated into the Earth when the Solar System formed.All rocks and minerals contain tiny amounts of these radioactive elements.

sedimentary dating-90

Professor Fouke's research was funded by the US National Science Foundation and has been accepted for publication in the Journal of Sedimentary Research.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.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.This finding is very important since the rate of precipitation controls the chemistry and shape of calcium carbonate crystals.Radiometric dating has been used to determine the ages of the Earth, Moon, meteorites, ages of fossils, including early man, timing of glaciations, ages of mineral deposits, recurrence rates of earthquakes and volcanic eruptions, the history of reversals of Earth's magnetic field, and many of other geological events and processes.

Calcium carbonate (the same material which clogs up kettles and makes water 'hard') is the most abundant mineral precipitate on the surface of Earth.

Radioactive elements are unstable; they breakdown spontaneously into more stable atoms over time, a process known as radioactive decay.

Radioactive decay occurs at a constant rate, specific to each radioactive isotope.

A commonly used radiometric dating technique relies on the breakdown of potassium (Ar in an igneous rock can tell us the amount of time that has passed since the rock crystallized.

If an igneous or other rock is metamorphosed, its radiometric clock is reset, and potassium-argon measurements can be used to tell the number of years that has passed since metamorphism.

So abundant, in fact, that it accounts for about 4% by weight of the Earth's crust.