Dating on earth
These layers often contained fossilized remains of unknown creatures, leading some to interpret a progression of organisms from layer to layer.
In the mid-18th century, the naturalist Mikhail Lomonosov suggested that Earth had been created separately from, and several hundred thousand years before, the rest of the universe. In 1779 the Comte du Buffon tried to obtain a value for the age of Earth using an experiment: He created a small globe that resembled Earth in composition and then measured its rate of cooling.
His value of 56 million years added additional evidence that Thomson was on the right track.
By their chemical nature, rock minerals contain certain elements and not others; but in rocks containing radioactive isotopes, the process of radioactive decay generates exotic elements over time.
The physicist Hermann von Helmholtz (in 1856) and astronomer Simon Newcomb (in 1892) contributed their own calculations of 22 and 18 million years respectively to the debate: they independently calculated the amount of time it would take for the Sun to condense down to its current diameter and brightness from the nebula of gas and dust from which it was born.
Their values were consistent with Thomson's calculations.
In Darwin's theory of evolution, the process of random heritable variation with cumulative selection requires great durations of time.
Other naturalists used these hypotheses to construct a history of Earth, though their timelines were inexact as they did not know how long it took to lay down stratigraphic layers.It is also difficult to determine the exact age of the oldest rocks on Earth, exposed at the surface, as they are aggregates of minerals of possibly different ages.Studies of strata, the layering of rocks and earth, gave naturalists an appreciation that Earth may have been through many changes during its existence.Dating Earth is an online dating site created for single people.Simply join for free and begin using the site to date, meet new friends, date and find love - all local to you.