Continental Drift Theory: Glacial Evidence and Plate Tectonics

How does the presence of glacial evidence support the Theory of Continental Drift?

1. Glaciers leave behind evidence such as carved valleys and rocks.

2. Valleys carved by glaciers have only been found in Antarctica.

Answer:

Glacial evidence, such as carved valleys and deposits found in presently warm regions, indicates these areas were once in colder climates, supporting Alfred Wegener's continental drift theory by suggesting continents have moved over time.

The presence of glacial evidence in currently warm regions indicates that these areas were once situated in colder, polar climates, which supports the idea that continents have moved over time. This movement would have placed the continents in different climatic zones throughout Earth's history—something that is a cornerstone of the continental drift theory. The discovery of glacial features in areas that are not currently conducive to glacier formation or maintenance is a clear sign that continents have drifted from their original positions.

Ice sheets and glaciers leave distinct geological features such as scratched and ground down rocks or deposits of sediment that can be traced back to their points of origin. This allows scientists to reconstruct past positions of the continents, lending weight to the theory postulated by Wegener and later developed into the modern understanding of plate tectonics.