Chapter 18, Problem 1RQ

To determine

Theevidence offered by Louis Agassiz to support that the ice age happened.

Answer to Problem 1RQ

The evidence offered by Louis Agassiz was that the mysterious erratics of Europe were left by enormous sheets of ice that had once covered much of the continent.

Explanation of Solution

An ice age is a period in the Earth’s history in which the climates were extremely cold, resulting in the existence or expansion of continental ice sheets and mountain glaciers. There are two stages within an ice age, where periods of cold climate are termed as ‘glacial periods’ or ‘glaciations’, and alternative warm periods that are called ‘interglacial’.

In 1837, Agassiz proposed that the Earth had been subjected to a past ice age. He proposed that ancient glaciers not only flowed externally from the Alps, but also on the plains and mountains of Europe. He observed that the slow-moving masses of glaciers could carry massive boulders, as well as sand and mud, because ice is a solid and had the power to support the weight of a rock.

He realized that unlike rivers, glaciers do not sort sediments as they flow and leave unsorted sediment later when they melt. Later in life, Agassiz traveled to the United States and identified many glacial features in North America's landscape, proving that the last ice age did not affect just Europe.