Specially equipped laboratories can do this with accuracy and precision.So, in general, few people quarrel with the resulting chemical analyses.So let’s take a closer look and see how reliable this dating method really is.
Both are complete atoms in every sense of the word.Geologists regularly use five parent isotopes to date rocks: uranium-238, uranium-235, potassium-40, rubidium-87, and samarium-147.In some cases, the isotopes eject particles, primarily neutrons and protons.(These are the moving particles measured by Geiger counters and the like.) The end result is a stable atom, but of a different chemical element (not carbon) because the atom now has a different number of protons and electrons.PART 1: Back to Basics PART 2: Problems with the Assumptions PART 3: Making Sense of the Patterns This three-part series will help you properly understand radiometric dating, the assumptions that lead to inaccurate dates, and the clues about what really happened in the past.
Most people think that radioactive dating has proven the earth is billions of years old.
So, for example, every carbon atom contains six protons and six electrons, but the number of neutrons in each nucleus can be six, seven, or even eight.
Therefore, carbon has three isotopes (variations), which are specified carbon-12, carbon-13, and carbon-14 (Figure 1).
Note that the carbon-14 (or radiocarbon) method is not used to date rocks because most rocks do not contain carbon. They must find rocks that have the isotopes listed above, even if these isotopes are present only in minute amounts.
Most often, this is a rock body, or unit, that has formed from the cooling of molten rock material (called magma).
Some isotopes are radioactive; that is, they are unstable because their nuclei are too large.