What are moraines?

Moraines are indeed defined as the material left behind after a glacier. When glaciers move, they erode the landscape, picking up rocks, soil, and debris, which then gets transported along with them. When the glacier retreats, it deposits this accumulated material, forming ridges or mounds known as moraines.

These deposits can vary in size and shape, often categorized into different types depending on their location in relation to the glacier. For instance, terminal moraines form at the edge of a glacier, marking its furthest advance, while lateral moraines accumulate along the flanks of the glacier. Moraines are significant features in glacial geography and provide insights into the glacier's past movement and the environmental conditions during its existence.

The other options refer to concepts that are related to glaciers but do not accurately define what moraines are. For example, waterlogged areas adjacent to glaciers are typically referred to as glacial wetlands, and fissures in the ice are known as crevasses. Mineral deposits can occur in glacial regions, but they do not constitute moraines.