What are medial moraines?

Medial moraines are stripes that appear on glaciers, like lines drawn by a giant pencil.

Imagine you're playing with your toy cars on a long, smooth road, now imagine the road is made of ice and it's moving slowly. A medial moraine happens when two smaller glaciers come together and merge into one bigger glacier. Each of these small glaciers has debris, like pebbles or dirt, that they carry along with them.

When the glaciers meet, the debris from both glaciers ends up in the middle of the new, bigger glacier, kind of like when you put two piles of toys together, and the ones in the middle are shared by both piles. As the big glacier moves forward, this shared pile stays on top, creating a striped line, which is the medial moraine.

It's like if you and your friend both brought snacks to share at lunch, when you put them together, the middle of the snack pile is what you both contributed!