It is almost the first thing I teach my first-year students. al., : Biostratigraphy: Time Scales from Graphic and Quantitative Methods,” , 2004, p. The rocks do date the fossils, but the fossils date the rocks more accurately.Ever since William Smith at the beginning of the 19th century, fossils have been and still are the best and most accurate method of dating and correlating the rocks in which they occur. 49.) “Are the authorities maintaining, on the one hand, that evolution is documented by geology and, on the other that geology is documented by evolution? Stratigraphy cannot avoid this kind of reasoning, if it insists on using only temporal concepts, because circularity is inherent in the derivation of time scales.” (O’Rourke, J.
Relative dating does not provide actual numerical dates for the rocks.
Fossils are important for working out the relative ages of sedimentary rocks.
Different species of ammonites lived at different times within the Mesozoic, so identifying a fossil species can help narrow down when a rock was formed.
Correlation can involve matching an undated rock with a dated one at another location.
Some of the most useful fossils for dating purposes are very small ones.