Earth’s geology and tectonics has created amazing geology and geologic features. This article briefly describes the deepest points and the highest points on Earth.
DEEPEST POINTS
There are actually two deepest points on Earth: the Mariana Trench in the Pacific Ocean, and the Dead Sea in Israel.
The Marianas Trench in the Pacific Ocean is the deepest point on Earth at about 11 km (6.8 mi). The highest mountain above sea level, Mount Everest, can fit neatly into the Marianas Trench with more than a mile to spare. The Marianas Trench is in the western North Pacific Ocean, southeast of the Mariana Islands, near Guam. The trench is actually the point where the Pacific and the Philippine tectonic plates meet, and the Pacific plate is forced under the Philippine plate. The deepest area of the Marianas Trench is Challenger Deep, at 10,900 meters, 35,760 ft. The sea pressure at that depth is 108.6 MPa, over one thousand times the standard atmospheric pressure at sea level. The Marianas Trench has been measured by American, British, Soviet, and Japanese vessels using echosounding devices, pressure depth devices, and bathyspheres.
The Dead Sea in Israel is the deepest point on land at 418 meters (1,371 feet) below sea level. The Dead Sea is inside the Jordan Rift Valley, which was formed when the Arabian tectonic plate moved away from the African tectonic plate. At that time the Mediterranean Ocean flooded the rift, but the flow of water was stopped when the Jordan Rift Valley rose to form the prehistoric Lake Gomorrah. As the freshwater lake evaporated and became saltier, the lake turned into Lake Lisan. Continued evaporation has shrunken the lake into the present-day Dead Sea, one of the saltiest bodies of water on Earth. There are no streams that flow out of the Dead Sea, and the Jordan River is the only river that flows into the Dead Sea.
HIGHEST POINTS
As with the deepest points on Earth, there are two highest points: Mount Everest on the border of Tibet and Nepal, and Mauna Kea in Hawaii.
Mount Everest is the highest mountain above sea level on Earth, at 8,848 meters (29,029 feet). Mount Everest is part of the Himalayan mountain range, and is located on the border of Sagarmatha Zone, Nepal, and Tibet, China. The Himalaya were formed by the titanic collision of the Indian tectonic plate with the Eurasian tectonic plate 50 million years ago, causing the crust to fold and up thrust to form the Himalayan mountains. The Indian plate is still moving, making the Himalayan mountains taller by the rate of one inch a year. Mount Everest is the lodestone for mountaineers and climbers, and has claimed 210 lives from 3,679 ascents. The first official ascent was by Sir Edmund Hillary and Sherpa Tenzing Norgay in 1953; the latest ascent in 2008. At the top of Mount Everest, the air pressure is one third of sea level pressure and the oxygen content drops, allowing water to boil at 70 degrees Celsius instead of 100 degrees Celsius. Snow never melts from the Himalayan mountain tops, giving the Himalaya its name, from the Sanskrit for “the abode of the snow”.
The highest mountain as measured from its base is Mauna Kea in Hawaii. From the ocean floor to the top of the sea it measures 5800 meters (19,000 feet), and rises another 4205 meters (13,796 feet). Even in though the Hawaiian Islands are the tropics, the summit of Mauna Kea is capped with snow in winter (in the Hawaiian language, mauna kea means “white mountain”). Mauna Kea is actually one of the volcanoes that form the island of Hawai’i (or the Big Island) in the Pacific Ocean. Now dormant, the volcano first formed about 4 million years ago when the Pacific tectonic plate moved over a magma hotspot in the Pacific. The hotspot was the source for the other volcanic islands in Hawaii that formed as huge volcanoes grew and slowly moved away from the hotspot. The Big Island is currently over the hotspot, but Mauna Kea is currently dormant. The last eruption of Mauna Kea was around 2460 BC, but another eruption in the next few thousand years is possible.
