Glacial Erratic

glaciers · geology · ice age

Carried by glaciers. Glaciers act like giant conveyor belts, picking up rocks and boulders and transporting them across huge distances, sometimes hundreds of kilometers away from their original home.

Out of place rocks. An erratic is easy to spot because it looks totally different from all the rocks around it. Scientists can tell it came from somewhere else by studying what type of rock it is.

Many different sizes. Erratics can be as small as pebbles or as enormous as houses. Big Rock in Alberta, Canada is one of the largest glacial erratics ever found.

Named after wandering. The word erratic comes from the Latin word errare, which means to wander or stray, because these rocks have wandered so far from home.

Evidence of ice ages. Finding glacial erratics scattered across a landscape tells scientists that glaciers once covered that area thousands of years ago.