Highest Mountains in the World

 

Ranked in Order

 

 

 

The Marianas Trench

or 'The Challenger Deep'

The Marianas Trench:
It's the deepest spot in any ocean of the world. It is located in the Pacific Ocean, just east of the Phillippines.
Nearby is the island of Guam, a U.S. Territory inhabited by natives identified as Chamorros.

The Marianas trench is sometimes called the 'Challenger Deep' because it was located and named after His Majesty's Ship 'Challenger' of the British Royal Navy in the 19th century.

The Marianas Trench's depth is about 10,924 m, or almost 11 km (7 miles). This is a height greater than any mountain on the surface of the earth!



What makes the Marianas Trench so interesting is the reason why it exists in the first place.
To understand what caused it to be formed will require a little information about plate tectonics, or the movement of pieces of the earth's crust.

Plate Tectonics is a description of the surface of the earth. The interior of the earth, called the mantle, is hot, molten lava. The solid crust, which is in pieces, floats on this magma, much like the shell of chocolate on a dipped icecream cone sits on the icecream.
As hot magma rises through cracks in the crust, it pushes the pieces of crust apart. In other places, pieces of crust are forced together, where they buckle to form mountains.

The oceanic crust is much heavier than the continental crust, so when these plates crash into each other, the oceanic plate plunges downward toward the molten mantle, while the lighter, continental plate rides up over the top. The forces driving the two plates together are really intense, so the underlying oceanic plate (the 'subducted' plate) creates a trench where it drags the edge of the continental crust down as it descends underneath. (check out the picture).

The really deep part of the ocean is in the bottom of the trench created by this subducting ocean crust. The Marianas Trench, for example, marks where the fast-moving Pacific Plate converges against the slower moving Philippine Plate.

Subduction also results in the formation of volcanoes. Over millions of years, the erupted lava and volcanic debris from the escaping magma pile up on the ocean floor, until a submarine volcano rises above sea-level to form an island volcano. The Phillippines, the Marianas Islands are examples of this. Such volcanoes are typically strung out in chains called island arcs. As the name implies, volcanic island arcs, which closely parallel the trenches, are generally curved. Because of their nearness to the the tectonic activity below, they experience numerous strong earthquakes.

Volcanoes can also form where the sea-floor crust passes over a 'hot spot' ... a spot where the crust is very thin and the hot layers below have broken through. As the moving crust passes over this hot spot, volcanoes form. The volcanoes sometmes reach all the way to the surface of the ocean, forming islands. As the crust continues to move, new volcanic islands are formed in sequence. This is how the Hawaiian Islands were formed; the island of Hawaii is currently over the hot spot. [Our thanks to Simon Jowitt of Camborne School of Mines in Cornwall, UK for correcting an error we made here].

Many strange creatures live in the perpetual dark and crushing pressure of this deep ocean floor ... but that's the subject of a future science page!

 

 

 

 

Longest-Lasting Echo
The longest echo detected in any building lasted 15 seconds. It was produced by closing the door of the chapel of the Mausoleum in Hamilton, South Lanarkshire, Scotland, built 1840–55.

 

 

Longest River
The Nile is credited as the longest river in the world. Its main source is Lake Victoria, in east central Africa. From its farthest stream in Burundi, in eastern Africa, it extends 6,695 km (4,160 miles) in length.

 

 

Largest Swamp
The world's largest tract of swamp is the Pantanal, in the states of Mato Grosso and Mato Grosso do Sul in Brazil. It is about 109,000 sq km (42,000 sq miles) in area.

 

 

Largest River To Dry Up
For several months a year, the 5,464-km (3,442-mile) Yellow River in China now dries up in Henan province. This is due to below-average rainfall, increased irrigation, and the industrial demands of a growing population.

 

 

Largest Delta
The world's largest delta is that created by the Ganges and Brahmaputra rivers in Bangladesh and West Bengal, India. It covers an area of 75,000 sq. km. (30,000 sq. miles).

 

 

Largest Basin
The largest river basin in the world is that drained by the Amazon. It covers about 7,045,000 sq km (2,720,000 sq miles).

 

 

Greatest River Flow
The Amazon Basin holds two-thirds of all the flowing water in the world. This is due to the fact it flows through the Amazon rain forest – the largest and wettest rain forest on the planet. The river is fed by over 1,000 tributary rivers, many of which are over 1,600 km (1,000 miles) long.

WANT TO KNOW MORE?
So why is the River Amazon so huge? Essentially because it is right on the equator. Around the "belt line" of the Earth lies a warm, tropical zone with over 1,016 cm (400 in) of rainfall every year. A lot of water falls onto the land surrounding the river into the "Amazon River drainage basin". Imagine this drainage basin is like a shallow dish covering the whole northern half of the South American continent. Whenever rain falls and lands anywhere in the basin, it all runs into the lowest place in the pan, which happens to be the Amazon River.

CHECK THIS OUT...
The Amazon Rainforest is the home of 250 species of mammals, 3,000 freshwater fish, 1,800 birds, 10,000 trees, and 70,000 other plant species.

 

1. What country has the longest coastline?

Canada has the longest coastline of any country. It is 56,453 miles long.

2. Which ocean is the deepest?

The Pacific Ocean has the greatest average depth of about 4282 meters.

3. What is the longest coral reef?

The Great Barrier Reef, along the continental shelf of northeastern Australia, is the longest coral reef measuring about 1,243 miles long.

4. Where is the deepest point on the ocean floor?

The Challenger Deep is the deepest point at 35,802 feet deep. It is located off the coast of Guam in the Marianas Trench. This depth was recorded in 1960 by the TRIESTE, a manned submersible owned by the U.S. Navy.

5. What is the longest river?

The Nile River, in Egypt, Africa, is 4,160 miles long and flows northward into the Mediterranean Sea.

6. What is the longest mountain range?

The Mid-Ocean Ridge is Earth's longest mountain range. The ridge circles the globe from the Arctic Ocean to the Atlantic Ocean passing into the Indian Ocean and crossing into the Pacific Ocean. This range is four times longer than the Andes, Rocky and Himalaya Mountains combined.

7. How tall was the tallest iceberg?

The tallest iceberg, measuring 550 feet, was located in 1958 off the coast of Greenland. This iceberg was only 5 feet 6 inches shorter than the Washington Monument in Washington, DC.

10. Which mountain is the tallest?

Although Mount Everest, at 29,028 feet tall, is often called the tallest mountain; Mauna Kea, an inactive volcano on the island of Hawaii is actually taller. Only 13,796 feet of Mauna Kea stands above sea level, yet it is 33,465 feet tall if measured from the ocean floor to its top. Mauna Kea would be 4400 feet taller than Mount Everest if they were placed next to each other. Also, if Mauna Kea was placed in the Marianas Trench, there would be about 2,000 feet between its top and the surface of the ocean.

11. What is the deepest lake?

Baykal Lake in the USSR, just north of Mongolia, is the deepest lake with a maximum depth of 5,315 feet.

 

 

 

The Andes Mountains are one of the longest and one of the highest mountain ranges in the world. They are located in South America and stretch 4,500 miles from north to south, along the west coast of the continent.

 

 

The Rocky Mountains, the great backbone of North America, extend 5,000 kilometers from New Mexico to Canada. The elevations range from about 1,500 meters along the plains to 4,399 meters, and the widths range from 120 to 650 kilometers (Lavender 1975). The Rocky Mountains are composed of many mountain ranges with unique ecological features. For example, 20 ranges make up the Rocky Mountains in and adjacent to Wyoming (Knight 1994). The natural beauty, abundant wildlife, and fresh water have attracted human inhabitants for the last 10,000-12,000 years (Fig. 1).

 

The Puerto Rico Trench is the deepest part of the Atlantic Ocean, with water depths exceeding 8,400 meters (figure 1). Its depth is comparable to the deep trenches in the Pacific Ocean. Trenches in the Pacific are located in places where one tectonic plate subducts or slides under another one. The Puerto Rico Trench, in contrast, is located at a boundary between two plates that slide past each other with only a small component of subduction. The trench is less deep where the component of subduction is larger. The unusually deep sea floor is not limited to the trench, but also extends farther south toward Puerto Rico. The Puerto Rico Trench is also associated with the most negative gravity anomaly on earth, -380 milliGal, which indicates the presence of an active downward force. Finally, a thick limestone platform, which was originally deposited in flat layers near sea level, is now tilted northward at a uniform angle. Its northward edge is at a depth of 4,200 m, and its southern edge can be found on land in Puerto Rico at an elevation of a few hundred meters. Many tectonic models have been proposed to explain this geologically fascinating, tectonically active region; however, none have gained acceptance, and the region remains poorly understood, largely because its underwater location makes it difficult to study.

Figure 2. Location of earthquakes as a function of depth and size in the northeastern Caribbean. Click image for larger view and more information.

Puerto Rico, the Virgin Islands to its east, and eastern Hispaniola to its west, are located on an active plate boundary zone between the North American plate and the northeast corner of the Caribbean plate (figure 1). The Caribbean plate is roughly rectangular, and it slides eastward at about 2 cm/yr relative to the North American plate. Motion along its northern boundary (in the plate boundary zone region) is dominantly strike-slip (a geological fault in which an adjacent surface moves horizontally), with a small component of shortening. In contrast, on its eastern boundary, the Caribbean overrides the North American plate, creating the island arc of the Lesser Antilles with its active volcanoes.

Figure 3. Probability for damaging ground motion at San Juan and Mayaguez in comparison to other seismic high-risk areas in the U.S. (e.g. Seattle). Graph courtesy of USGS. Click image for larger view and more information.

The geologic settings of Puerto Rico and the Virgin Islands have created or contributed to several pressing societal issues related to human safety, environmental health, and economic development. Over 4 million U.S. citizens live on these islands, mostly along the coast. Because the island lies on an active plate boundary, earthquakes are a constant threat, and the densely populated coastal areas are vulnerable to tsunamis. Erosion is a concern in many coastal areas, but is particularly serious to island economies that rely heavily on the tourist industry.

The region has high seismicity and large earthquakes (figure 2). Examples include a magnitude 7.5 earthquake centered northwest of Puerto Rico in 1943, and magnitude 8.1 and 6.9 earthquakes north of Hispaniola in 1946 and 1953, respectively. Historically, other large earthquakes have also struck the area, such as one in 1787 (magnitude~8.1), possibly in the Puerto Rico Trench, and one in 1867 (magnitude~7.5) in the Anegada Trough (figure 1). A draft U.S. Geological Survey (USGS) hazard map places equal probability for damaging ground motion for Mayaguez in western Puerto Rico as for Seattle, Washington. Other Puerto Rican cities also have substantial risk.

Figure 4. Numerical simulation of the 1918 Puerto Rico tsunami showing calculated inundation of the Aguadilla coast in northwest Puerto Rico. Image courtesy of USGS. Click image for larger view and more information.

The hazard from tsunamis is also apparent. Immediately after the 1946 earthquake, a tsunami struck northeastern Hispaniola and moved inland for several kilometers. Some reports indicate that nearly 1,800 people drowned. A 1918 magnitude 7.5 earthquake resulted in a tsunami that killed at least 91 people in northwestern Puerto Rico (figure 4). Eyewitness reports of an 1867 Virgin Islands tsunami gave a maximum wave height of >7 m in Frederiksted, St. Croix, where a large naval vessel was left on top of a pier. Essentially, all of the known causes of tsunamis are present in the Caribbean -- earthquakes, submarine landslides, submarine volcanic eruptions, subaerial pyroclastic flows into the ocean, and major tsunamis called teletsunamis. Because of its high population density and extensive development near the coast, Puerto Rico has a significant risk for earthquakes and tsunamis.