Here's how it works:
* Faults and Intrusions are Younger: The Law of Cross-Cutting Relationships states that a geologic feature that cuts through another feature must be younger.
* Faults: If a fault cuts through rock layers, the fault is younger than the rock layers it displaces.
* Intrusions: If an igneous intrusion (like a dike or sill) cuts through existing rock layers, the intrusion is younger than the layers it intrudes into.
Example:
Imagine you see a rock layer with a fault running through it. The fault has displaced the rock layer, showing it was formed after the rock layer was deposited.
Key Points:
* This law is based on the idea that something can't be cut or disrupted by something that doesn't yet exist.
* It's a fundamental principle in relative dating, which helps scientists understand the order of geological events without relying on numerical ages.
Let me know if you'd like to explore other principles of relative dating!
