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主题：Gamburtsev mountains的起源

1. Hotspot

One theory is that the Gamburtsev range was originally created by the activity of a volcanic "hotspot." Hotspots are extremely hot regions located beneath Earth's crust. A volcanic mountain can be created when a hotspot forces hot molten rock, or magma, through the crust onto Earth's surface. A series of mountains such as the Gamburtsev range could form as the crust slowly moved over a hotspot.

1.First, the hot spot theory. Well, hot spots can be detected long after mountains have been formed, so we should be able to find the specific hotspot that caused the Gamburtsev mountains to form. The problem is that we cannot find a hot spot that's near enough the Gamburtsev mountains to be a likely possibility. The nearest hot spot we know about is five thousand, five hundred kilometers away, which seems to be too far away for the hot spot to be associated with the mountains. Since we haven't found a hot spot that's near enough. This theory is pretty short on evidence.

2. Continental Plate Collision

Another way mountains can form is when moving regions of Earth's crust, called continental plates, collide. The force of such collisions can lift up mountain ranges. There is evidence that the Antarctic plate underwent a collision with another plate 250 million years ago. It is possible that the Gamburtsev range was created during that collision.

2. Second, the continental plate collision theory. According to this theory, the Gamburtsev mountains were formed two hundred fifty million years ago. The problem is that if the mountains were two hundred fifty million years old, they would show signs of their age. For example, they would be worn down quite a bit by erosion by now. Their peaks would be rounded, and they wouldn't be very tall. However, that's not what the mountains look like at all their peaks are sharp and tall, which suggests that they are relatively young mountains. So judging by their appearance, they're unlikely to be as old as the last major plague collision.

3. Ice

According to a third theory, the Gamburtsev range was created through the impact of Antarctic ice. 14 million years ago, most surface water on the Antarctic continent became frozen. A thick layer of ice has covered Antarctica's surface ever since. The impact of the ice on the underlying crust may have caused the mountains to form. An ice layer can grind away rocks underneath it and make Earth's crust thinner in some areas. A thinner crust is more sensitive to the geological forces beneath it and can be easily lifted to form a mountain range.

3. The third theory suggests that the mountains were created while antarctica was covered by a thick layer of ice. The problem is that when we analyze some features of the Gamburtsev mountains, especially the mountain valleys, it's clear that they've been partly shaped by running water by rivers, so if some parts of these mountains were shaped by rivers, the mountains must have been created before all the surface water in Antarctica froze and the whole continent became covered by ice.