Final answer:
Broad glaciers with area greater than 50,000 square kilometers are ice sheets, which are large ice masses that sit on top of continents.
Step-by-step explanation:
Broad glaciers not confined by topography and with area greater than 50,000 square kilometers are ice sheets.
Ice sheets are large ice masses that sit on top of continents. For example, Antarctica is covered by an ice sheet that is two to three miles high. These ice sheets flow across the rocky surface and erode sediment. When ice sheets reach the coastline, the sediment is carried by ocean currents and eventually deposited.