Near the Ross Sea and along the width of the continent stands the Transantarctic chain.
The main feature of this mountain range are the dark slopes of dolerite, a basaltic instrusione horizontally above the rocks called "base of Beacon." The thickness of this layer is of the order of 500 meters, has a very smooth layer that extends for a long distance. E 'dated between 147 and 163 million years ago.
Instead, the so-called "stand Beacon" is composed of horizontal deposits of sand and other (then mainly sandstones) of rivers and lakes that have accumulated over a long period of time between 400 and 200 million years ago.
The name of Beacon sandstone was given by HT Ferrar the geologist of the expedition of Scott (1901-04).
The video has been documented helicopter flying over the glacier to reach the Ferrar Beacon Valley, one of the Dry Valley, at about 1300-1400 meters above sea level.
The Dry Valley are called so for the near absence of rainfall, mainly due to their orientation with respect to the chain and precipitation from the ocean.
The glaciers that descend from the plateau did not melt waters and in fact there are no moraines.
Another feature of the Dry Valley soil "polygons" .... The dry soil, but frozen, takes configurations to polygons, visible from above.
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