Describe relative absolute dating techniques
Relative dating and radiometric dating are used to determine age of fossils and geologic features, but with different methods.
Relative dating uses observation of location within rock layers, while radiometric dating uses data from the decay of radioactive substances within an object.
Continue Reading Relative dating observes the placement of fossils and rock in layers known as strata.
Basically, fossils and rock found in lower strata are older than those found in higher strata because lower objects must have been deposited first, while higher objects were deposited last.
Relative dating helps determine what came first and what followed, but doesn't help determine actual age.
Radiometric dating, or numeric dating, determines an actual or approximate age of an object by studying the rate of decay of radioactive isotopes, such as uranium, potassium, rubidium and carbon-14 within that object. This rate provides scientists with an accurate measurement system to determine age.
For example, carbon dating is used to determine the age of organic materials.
Once something dies, it ceases taking in new carbon-14, and the existing carbon-14 within the organism decays into nitrogen at a fixed rate.
In the past, relative dating methods often were the only ones available to paleoanthropologists.As a result, it was difficult to chronologically compare fossils from different parts of the world.However, relative methods are , which is that if there are layers of deposits, those laid down first will be on the bottom and those laid down last will be on the top. However, geological strata are not always found to be in a neat chronological order.Wind and water erode strata and some areas are uplifted or even tilted.These processes result in All of these processes confuse the stratigraphic record.
In many cases, however, it is possible to reconstruct the original sequence of strata so that they can be used for relative dating.