Discovery Science: Earth – Mountain Summits
Since the beginning of time, people have had a special relationship to mountain summits. While scientists see a summit as the result of tectonic processes, climbers behold a formidable challenge.
Most mountain summits are peaks in a range of mountains, although individual summits can also ascend from a plain. Summits are normally formed when sections of the Earth’s crust located at higher elevations are eroded; they can also be erected by lava that streams over the Earth’s surface.
Summits vary in terms of appearance: they can consist of a large, boulder-like, craggy rock or be formed of free-standing massifs with abrupt vertical drops, a volcanic cone, or domes covered in perennial ice.
Mighty mammoths
The highest summits on Earth are the “eightthousanders,” so named because they all reach heights of over 26,247 feet (8,000 m). Ten of these 14 gigantic mountains are found in the Himalaya. The summit that towers over them all at 29,029 feet (8,848 m) is Mount Everest. However, to be exact, this summit is actually exceeded by Mauna Kea in Hawaii.
Although this volcano reaches only about half of Everest’s height, together with its underwater base, its overall altitude is approximately 33,500 feet (10,211m). The highest volcano on any continent, with a height of 22,615 feet (6,893 m), is Ojos del Salado, located on the border of Argentina and Chile.
In Europe, the highest mountain summit is either Mont Blanc in the Alps or Elbrus in the Caucasus, de- pending on how the boundary between Europe and Asia is defined.
Monoliths and monadnocks
The largest monolith on Earth is Mount Augustus in western Australia. Much more famous, however, is Ayers Rock, located in the same country. Rising abruptly from their surroundings, such monadnocks, also known as inselbergs, are the remains of contiguous plateaus that have been worn down by erosion or weathering.
A good example is Monument Valley in North America, with its many striking rock formations. Table Mountain in Cape Town, South Africa, was also formed from a rock layer that survived the eroding teeth of time.
EARLY EVEREST ASCENTS
Called Sagarmatha (“king of the heavens”) in Nepalese and Chomolungma (“mother goddess of the earth”) in Tibetan, this Himalaya mountain got its English name from the British surveyor George Everest.
The first people to conquer this summit were Edmund Hillary of New Zealand and Sherpa Tenzing Norgay on May 29, 1953. In 1975 Japan’s Junko Tabei was the first woman to reach the peak. Reinhold Messner made the first as-cent without an oxygen mask in 1978.