Who developed radiometric dating
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After all, textbooks, media, and museums glibly present ages of millions of years as fact.
The top rock layer might have been limestone containing lots of snail fossils.People have been studying earth and rock formations for a very long time.In the 19th century, geologists took a closer look at the layers that they saw in sedimentary rocks.Keep in mind that these three eras are all grouped within the Phanerozoic eon. Well, that one doesn't get to have any eras inside it.We don't have a lot of information about it, so we leave it as one big chunk in geologic history.