Relative age dating geology
These relative dating principles can be applied in the field, so they're really valuable to geologists who spend most of their time researching rocks in nature.
From these principles, we can also learn about the geologic history of the rock or fossil.
To understand this better, consider a four-layer cake. It wouldn't be possible for the other layers to be added without the bottom layer first.
This same process applies with each layer to the cake added.
However, it does not cut layers D and E, so those layers are younger than Fault F.
Law of inclusions: This law states that when a rock contains pieces or fragments (also called inclusions) of another rock, these pieces or fragments must be older.
The reason Fault F is younger than layers A, B, and C is because it cuts the layers.Today there are two common practices for dating rocks and strata. Geologists use what they see and some simple strategies to relative date the rock layers found in the Grand Canyon.The first is called absolute dating, where geologists use radioactive decay to determine the actual age of a rock. Let's say you are a geologist who is tasked with dating the rocks found in the Grand Canyon, and you must do so in the canyon without the aid of any laboratory equipment. Relative dating doesn't really give us an actual 'age,' but it does put things in sequential order.You can't start with the top layer and add the ones under it since there would be nothing to build on.Principle of later continuity: The principle of lateral continuity says that rocks continue in all lateral directions, even if you can't see them on the surface.
So, basically it's the difference between saying 'I'm 25 years old, and my sibling is 20 years old' and 'I'm older than my sibling.' Geologists use a variety of techniques, or principles, to determine the relative age of a rock unit.