ELI5: Explain Like I'm 5

Gardner's relation

Gardner's relation is a fancy way of talking about a rule that tells us how strong rocks are. Think of rocks like big, heavy lego blocks. Some lego blocks are easy to snap apart, while other blocks are much harder to break. Rocks are the same way - some rocks are weak and crumble easily, while others are very strong and hard to break.

Gardner's relation says that the strength of a rock depends on how tightly packed together its grains are. Imagine that each grain in a rock is like a little ball. If the balls are packed together very tightly, the rock will be stronger. But if there's lots of space between the balls, the rock will be weaker. That's because the balls can move around more easily and the rock won't hold together as well.

Scientists use Gardner's relation to study rocks and figure out how they behave over time. This way they can understand things like earthquakes and landslides, and predict how rocks will hold up under pressure. So even though Gardner's relation sounds complicated, it's really just a way to understand why some rocks are strong and others are weak.