Radiometric dating not accurate Sexsussex
He inferred that where the layers are not horizontal, they must have been tilted since their deposition and noted that different strata contain different kinds of fossil.Robert Hooke, not long after, suggested that the fossil record would form the basis for a chronology that would “far antedate ...The second referred to such topics as the detailed shape of the earth (bulging slightly at the equator) and the dynamics of the earth-moon system.The third referred to the heat of the sun, particularly the rate at which such heat is being lost, compared with the total amount of energy initially available.
The Talmudic rabbis, Martin Luther and others used the biblical account to extrapolate back from known history and came up with rather similar estimates for when the earth came into being.
Nevertheless, by the late 19th century the geologists included here had reached a consensus for the age of the earth of around 100 million years.
Having come that far, they were initially quite reluctant to accept a further expansion of the geologic timescale by a factor of 10 or more.
It was not until 1926, when (under the influence of Arthur Holmes, whose name recurs throughout this story) the National Academy of Sciences adopted the radiometric timescale, that we can regard the controversy as finally resolved.
Critical to this resolution were improved methods of dating, which incorporated advances in mass spectrometry, sampling and laser heating.And we should resist the temptation to blame them for their resistance. Different methods of measurement (such as the decay of uranium to helium versus its decay to lead) sometimes gave discordant values, and almost a decade passed between the first use of radiometric dating and the discovery of isotopes, let alone the working out of the three separate major decay chains in nature.