Fossil carbonates of biological origin like foraminiferas, bivalves, corals and ostracodes are investigated to reconstruct past climate, circulation in the ocean or the history of lakes.
It is clear that the sedimentary rock was deposited and folded before the dyke was squeezed into place.
his document discusses the way radiometric dating and stratigraphic principles are used to establish the conventional geological time scale.
It is not about the theory behind radiometric dating methods, it is about their , and it therefore assumes the reader has some familiarity with the technique already (refer to "Other Sources" for more information).
the pattern was caused by the way the magma was emplaced or how it crystallized. But Drs Humphreys and Baumgardner realized that in other cases there were many independent lines of evidence that suggested that huge amounts of radioactive decay had indeed taken place.
(These include the variety of elements used in ‘standard’ radioisotope dating, mature uranium radiohalos and fission track dating.) It would be hard to imagine that geologic processes alone could explain all these.