Why does western North America have volcanoes, earthquakes, mountain ranges, and small valley glaceiers and why are these same features not present on the eastern part of the continent? How could this situation be reversed?
The presence of volcanoes, earthquakes, mountain ranges, and small valley glaciers in western North America is due to a geological process called plate tectonics. Plate tectonics is the theory that the Earth's outer shell, or lithosphere, is divided into several large, rigid plates that are constantly moving.
In western North America, there are several plate boundaries where tectonic plates interact and collide. The primary plate boundary is known as the Pacific Plate and it is converging with the North American Plate. This collision has resulted in the formation of the Cascade Range in the Pacific Northwest, which includes volcanoes like Mount St. Helens and Mount Rainier. Additionally, the San Andreas Fault is another prominent example of the tectonic activity in this region, leading to frequent earthquakes.
On the other hand, the eastern part of North America is located in the interior of the North American Plate, which is relatively stable compared to plate boundaries. As a result, there is less tectonic activity in this region, leading to a lack of volcanoes, earthquakes, and mountain ranges.
To reverse this situation, it would require a significant change in plate tectonics. This could happen if the North American Plate were to collide with another tectonic plate, similar to what is happening in western North America with the Pacific Plate. However, such a scenario is highly unlikely as it would require massive geological forces over millions of years.
In summary, the presence of volcanoes, earthquakes, mountain ranges, and small valley glaciers in western North America is a consequence of plate tectonics, while the relative absence of these features in the eastern part of the continent is due to the stable interior of the North American Plate. To reverse this situation, a major change in plate tectonics would be necessary, which is unlikely to occur.