It is believed the that the Appalachian Mountains used to reach heights of nearly 20,000 feet. Over the last 300 million years since the mountains were formed, there has been enough erosion to flatten the mountains. However, despite all of the erosion, Virginia still has its mountain ranges. Which is NOT a major cause of the erosion of the mountains? A)water run-off B)wind C)coal mining D)rain

Coal mining is not a major reason for the erosion of the Appalachian Mountains.

Explanation:

The Appalachian Mountains are one of the oldest mountain chains in the world. They have formed over 300 million years ago, being one of the highest, if not the highest mountains in the world in their prime. As we can see nowadays though, these mountains are not anywhere near to being the highest, but instead have a medium and small height, depending on which part of them.

The reason that these mountains lost much of their elevation is the erosion. 300 million years is a very long time, and constantly being affected by erosion has led to gradual losing of rock layers, flattening, and having gentle slopes. The rainfall, water run-off, wind, high and low temperatures, ice, have all had their impact on the erosion of the Appalachians. Over time, in a few million years, what will be left of this mountain range would be smaller and larger hills intersected with lowlands.