How can the Earth be relatively young when scientists tell us that rocks are billions of years old?
Textbooks, popular science articles and museum displays are always careful to include and even emphasize the age in Earth history in which early creatures lived. Just how do scientists know the age? Have they somehow determined the age of the actual fossil or the rock in which it was found? The true answer is neither. However, when pressed, geologists will argue that it is the age of the fossil that determines the age of the rock. How then was this done? Not by using fossil dinosaur bones or any other terrestrial creature but, it is said, with fossil seashells. So what physical method was used to determine the age of the seashells? None, and although loosely ascribed to radiometric methods, it was all done long ago by committee!
Georges Cuvier (shown here) was a Lutheran and product of the French Revolution. In 1812, after observing that the multiple rock stratum beneath the streets of Paris had originally been layers of sediment, he wrote that these were caused by multiple and sequential floods. Moreover, the extent of these sediments and, therefore, the floods that deposited them had to have been caused by rising sea levels that would also have devastated most of the animals and plant life on Earth. Local rivers were recognized as insufficient to have supplied all the water. It was further argued that isolated geographical areas had always been spared and the living species – including man – had propagated themselves anew from these areas. The last of these catastrophes was the worldwide Genesis Flood, but in this case, the living things had been spared on the ark of Noah. Cuvier's theory seemed to account for the fossil record and permitted as many years as were required by geology for the catastrophe-repopulation cycles. The theory also said that the Bible had simply provided mankind with the record since the quiet time before the Genesis flood. Cuvier's theory – involving sequential, partial floods rather than a single, global flood – became vary popular among evangelical Christians in England. However, none were aware that the theory had prepared the ground for belief in Darwin's evolution to be declared five decades later.
In the 1830s, Charles Lyell and his committee of geologists, under the umbrella of' the Royal Society in London, concluded that rising sea levels would eventually mean a sequence of near global, if not actual, global floods, making Noah and his ark essential. Even to many Christians of that day, a global flood posed difficulties about the origin of the colored people because it was taken for granted that Noah's eight-member family was Caucasian white! Then, in 1841 on a visit to Italy, Lyell had his epiphany at the ancient Roman temple of Serapis. Here he saw evidence that floods could be caused not by rising sea levels but by the land sinking below sea level, accepting sediments, and rising again. Thus, the origin of the sedimentary rocks could be without a worldwide flood and the necessary and embarrassing account of Noah and his ark.
Attempts were made by Lyell and his "committee" to estimate the time taken to deposit each of the sedimentary layers, but this work was abandoned because the results amounted to only a few hundred thousand years – far too short for "development" (i.e., the evolution of life and life forms). Of far greater importance was to know the elapsed time for evolution of the species between each flood. However, this was elusive since it supposedly took place between the floods while the fossil remains of the evolved life forms were mixed and resided in the subsequent sedimentary layer. In other words, by adopting sequential floods, any land-based evolution took place between each flood, but physically this time was represented by the cracks between the sedimentary layers.
Since the early 1800s, men who were concerned with digging canals or tunnels learned that almost all sedimentary rocks contained seashells. Moreover, these shells were roughly in the same order, and thus it was possible to follow and identify given rock seams. The gentlemen geologists working with Lyell also learned about these shells and began to systematize them at first by Epoch name (e.g., Pleistocene, Micene, Eocene, etc.). It is emphasized that these shells are not in any evolutionary order of, say, simple to complex; nevertheless, they are useful to geologists to identify stratum. Ages were later assigned to these index fossils by committees and, while the working geologist has no purpose for this, the figures served to support the alleged periods in Earth's geological history and later the theory of evolution.
Darwin's theory appeared in 1859 and required that life begin spontaneously on Earth by the chance association of certain atoms to form molecules, then to form the first cells of life. The likelihood of this happening was remote, but given enough time, all things were believed to be possible. Then, in the 1920s, the Potassium/Argon radiometric dating method was developed, and values in millions of years obtained for crystals in the igneous basement rock beneath the sedimentary layers.
A committee of senior geologists declared the age of the Earth to be 2 billion – that's two thousand-million years old. This rounded figure satisfied the theory of evolution at the time and appeared in the school textbooks for the next forty years. Then, in 1956, Holmes claimed that his work with the Uranium/Lead radiometric method showed that the Earth crusted over from the molten state 4.7 billion years ago.
It was about this time that the electron microscope was developed and the extreme complexity of molecular life had become evident. The immediate solution was to permit more time for life to have evolved, and Holmes' figure for the overall age of the Earth was quickly adopted by a later committee. To this day, 4.7 billion years is still the textbook-quoted age of the Earth with very few people being aware that it is based on a claim by a radiometric measurement that is itself shot through with multiple assumptions and with no way of being calibrated!
Related links from other sites: How Old is the Earth?