Principles of relative age dating
If, in the year AD 1600, you had asked an educated European how old the planet Earth was and to recount its history he would have said that it was about 6000 years old and that its ancient history was given by the biblical account in Genesis.
If you asked the same question of an educated European in AD 1900 you would have received a quite different answer.
The rise of science produced a major change in attitude.
In the pre-scientific world view the issue of the age of the Earth was a theological question.
The physical models were open to question and, in retrospect, were naive. It became quite clear that many areas of the Earth had alternated between being land and being covered by seas, that there had been extensive slow sedimentation, that the mountains had not been created in situ as is but rather had a long history of slow deformation, and that long periods of erosion had shaped the Earth everywhere.
By the early 1800's it was generally accepted that the Earth had a long history. The uniformatarians (Hutton 1788, Lyell 1830) pictured the Earth as being indefinitely old.
The story of this great change in the conception of the history of Earth is not a simple one.
By the end of the 18'th century it was clear that the Earth had a long and varied history. The major debate was between the catastrophists, e.g., Cuvier, who held that the history of Earth was dominated by major catastrophic revolutions and the uniformitarians, e.g.
Many authors choose to present the history of a complex subject by breaking it up into major threads and following the history of each thread separately.
I have chosen instead to provide a chronology of significant works and their authors with a view to providing a sense of how perspectives on Geology changed over time.
Descartes, however, attempted to discern a physical history of the Earth.
His account was plausible by the immature standards of the Science of his times; however it quite definitely did not match the Biblical account of a completed creation in six days.In this period a number of comprehensive cosmogonies were proposed.These were long on armchair speculation and short on substantive supporting evidence.There were various attempts to estimate the Earth's age, working back from sedimentation rates and other geophysical phenomena.