Did you know that plateaus cover about 45% of the Earth’s land? These flat, elevated areas are a key feature of our planet. They rise sharply from the surrounding land on at least one side. Plateaus are among the main landforms, along with mountains, plains, and hills. They are found on every continent, with Asia having the most.
Plateaus are different from mountain ranges because they are very flat. They have low relative relief and some height. The average height of plateaus is about 1,214 meters above sea level. Exploring places like the Colorado Plateau in the U.S. or the African Plateau is truly captivating.
Key Takeaways
- Plateaus cover approximately 45% of the Earth’s land surface.
- The average elevation of plateaus is around 1,214 meters above sea level.
- Plateaus are found on every continent, with the largest concentration in Asia.
- Plateaus differ from mountain ranges in their remarkable flatness and low relative relief.
- Plateaus are one of the four major landforms, alongside mountains, plains, and hills.
Table of Contents
What is a Plateau?
Definition and Key Characteristics
A plateau is a flat, elevated landform that rises sharply above the surrounding area on at least one side. It is one of the four main landforms on Earth, along with mountains, plains, and hills. About one-third of the planet’s land surface is covered by plateaus.
The main features of plateaus include:
- A flat, elevated surface
- Steep slopes or escarpments on at least one side
- Found on every continent
- Covering about a third of the Earth’s land surface
Plateaus form through different geologic processes, like heating the lithosphere, crustal shortening, and volcanic activity. These elevated landforms pose unique challenges for building and real estate projects. This is because of their steep rise from the surrounding areas.
| Plateau Statistic | Value |
|---|---|
| Percentage of Earth’s land surface covered by plateaus | 33% |
| Area of the largest plateau – the Tibetan Plateau | 2.5 million km² |
| Approximate age of the Deccan Plateau in India | 65 million years |
“Plateaus are extensive land areas with a relatively level surface raised sharply above adjacent land on at least one side, resembling a tableland.”
Types of Plateaus
Plateaus are diverse, each with unique features and origins. The main types are dissected and volcanic plateaus.
Dissected Plateaus
Dissected plateaus form when the Earth’s crust moves up due to tectonic plates colliding. This creates a flat, high area of land. The Colorado Plateau in the western United States is a great example, shaped by uplift.
Volcanic Plateaus
Volcanic plateaus, on the other hand, are built up by many small volcanic eruptions and lava flows. The North Island Volcanic Plateau in New Zealand shows how volcanic activity can create a plateau.
Dissected plateaus are shaped by tectonic forces. Volcanic plateaus, however, are formed by volcanic eruptions and lava flows that fill in the terrain.
| Dissected Plateaus | Volcanic Plateaus |
|---|---|
| Formed by upward movement of Earth’s crust due to tectonic plate collision | Formed by numerous small volcanic eruptions and lava flows |
| Example: Colorado Plateau in western United States | Example: North Island Volcanic Plateau in New Zealand |
| Shaped by tectonic forces | Shaped by volcanic activity |
Plateaus, whether dissected or volcanic, are key parts of our planet. They cover about one-third of the Earth’s land. Knowing how they form helps us understand our world’s geological history and features.
Formation of Plateaus
Plateaus are high and flat areas of land. They form through different tectonic processes. Volcanism, crustal shortening, and thermal expansion of the Earth’s crust are the main reasons.
Volcanism is one way plateaus form. Repeated lava flows and eruptions build up a plateau over time. The Columbia Plateau in the Pacific Northwest of the United States is a great example.
Crustal shortening is another key process. It happens when one block of the Earth’s crust is pushed over another. This thickens the crust and creates elevated plateaus. The Altiplano plateau in South America is a result of this.
Thermal expansion also plays a role. It causes uplift and the formation of flat, elevated plateaus. The East African and Ethiopian plateaus were formed this way.
The formation of plateaus is complex. Often, volcanism, crustal shortening, and thermal expansion work together. They shape the landscape over millions of years.
| Plateau | Formation Process | Key Details |
|---|---|---|
| Columbia Plateau | Volcanism | Formed by repeated lava flows and volcanic eruptions |
| Altiplano | Crustal Shortening | Part of the Andes mountain range, created by one block of crust being thrust over another |
| East African and Ethiopian Plateaus | Thermal Expansion | Formed by uplift due to thermal expansion of the underlying lithosphere |
The formation of plateaus is a complex and fascinating process. It involves a combination of tectonic forces. These forces shape the high, flat landscapes we see around the world.
Erosion’s Impact on Plateaus
Plateaus, those remarkable high-altitude landforms, face erosion’s relentless forces. Over time, erosion reshapes these elevated landscapes. It forms captivating caprock surfaces, carves deep valleys, and isolates outliers.
Caprock, Valleys, and Outliers
The soft rock atop a plateau often erodes, leaving a hard caprock. This caprock protects the plateau from further damage. We see this in places like the Columbia Plateau and the Colorado Plateau.
Rivers and streams carve deep, winding valleys through plateaus. The Columbia River has carved a remarkable path through the Columbia Plateau, creating a visual masterpiece.
Extensive erosion can break up a plateau into smaller sections called outliers. These outliers, made of dense, ancient rock, are often the last remnants of a once-formidable plateau. The Colorado Plateau has iconic outliers.
“Plateaus are not immune to the relentless forces of erosion, which can significantly reshape their features over time.”
The interaction between plateaus and erosion shows our planet’s dynamic nature. As these high-altitude landforms evolve, they continue to captivate and inspire us. They provide a window into the ever-changing face of the Earth.
Largest Plateau in the World
The Tibetan Plateau is in Central Asia, the biggest and highest plateau on Earth. It covers an area of 970,000 square miles (2,500,000 square kilometers). It shows the power of tectonic forces and our planet’s resilience.
This plateau is over 14,800 feet (4,500 meters) high. It’s called the “Roof of the World.” It has the Himalayas and is the source of many rivers like the Brahmaputra, Indus, and Yangtze.
The Tibetan Plateau is huge. It’s 1,600 miles (2,500 kilometers) long and 620 miles (1,000 kilometers) wide. It’s a geological wonder that fascinates many.
Despite the cold, the plateau has a lot of life. It’s home to the Tibetan Antelope and the Snow Leopard. It’s a place of great biodiversity.
“The Tibetan Plateau is not just a geographical feature; it is a living, breathing entity that has shaped the history, culture, and livelihoods of the people who call it home.”
The plateau is important for the climate. It’s a big freshwater reservoir and shows the effects of climate change. Its glaciers have retreated a lot in 50 years, showing we need to protect it.
In a world of cities and factories, the Tibetan Plateau reminds us of nature’s power. It’s a place that shows the beauty of our world. Whether you love geology, nature, or just beauty, the Tibetan Plateau will impress you.
Oceanic Plateaus
Under the vast oceans, a surprising feature exists – the oceanic plateau. These flat-topped areas are split into two types: those with continental crust and those with igneous rock. The igneous ones are key in the Earth’s surface evolution, connecting old continental crust to new oceanic crust.
There are 184 oceanic plateaus worldwide, covering 18,486,600 km2. This is about 5.11% of the ocean’s surface. The South Pacific, around Australia and New Zealand, has the most of these formations.
| Ocean Region | Number of Oceanic Plateaus | Average Area (km2) |
|---|---|---|
| Arctic Ocean | 12 | 99,480 |
| Indian Ocean | 37 | 136,130 |
| North Atlantic Ocean | 36 | 45,230 |
| South Pacific Ocean | 50 | 141,100 |
Oceanic plateaus are more than just interesting features. They are crucial for the growth of continental crust. The igneous ones, in particular, are unique, with their own composition and density.
Oceanic plateaus have greatly influenced global climate over time. Their evolution is linked to mass extinctions, black shale formation, and sea level changes. They are key to understanding our planet’s dynamic landscape.
“Oceanic plateaus have largely shaped global climate through geological history.”
As we explore our planet, studying these oceanic plateaus will give us more insights. They help us understand the complex processes that have shaped our Earth.
plateau Geomorphology
A plateau is a high, flat area that can stretch for hundreds or thousands of kilometers. The Plateau of Tibet is a great example. You can drive over most of it, even though it’s over 4,500 meters high. It’s flatter than many cities.
Even plateaus dissected by rivers, like the Colorado Plateau, have flat tops. But deep canyons cut through them, making them interesting.
Plateaus vary in size, from a few square miles to thousands. The Colorado Plateau in the USA is huge, covering about 130,000 square miles. The Columbian Plateau in the Pacific Northwest is smaller, at 63,000 square miles. Auyantepui in Venezuela is a tiny plateau, just 257 square miles.
Some scientists only call a high plain a plateau if it’s made of flat-lying rocks. Dana suggested a height of 1,000 feet as a minimum for a plateau. Fenneman said plateaus can be flat or have deep valleys.
Powell used the term “diastrophic plateaus” for areas that have been pushed up by tectonic forces. Fairbridge talked about how sea level changes can affect the formation of plateaus.
The Tibetan Plateau: The Highest Plateau in the World
The Tibetan Plateau is the highest place on Earth, with an average height of almost 15,000 feet. It covers almost one million square miles in central Asia. It’s still growing because of tectonic forces.
The Deoasai Plains in Deosai National Park, Pakistan, are the second highest. They cover 1,200 square miles and are about 13,497 feet high.
“Plateaus can range in size from covering a few square miles to extending over thousands of square miles.”
The geomorphology of plateaus is unique. They have flat surfaces and uniform elevations. This is due to erosion, tectonic uplift, and volcanic activity. Studying plateaus helps us understand the Earth’s history and how it changes.
Tectonic Processes Behind Plateau Formation
Plateaus are vast, elevated landforms created by complex tectonic processes. These include volcanism, crustal shortening, and thermal expansion of the Earth’s crust. Each process has its own role in forming a plateau.
Volcanic activity helps build plateaus through lava flows. These flows solidify and pile up, creating a flat, elevated area. Over time, this area becomes a plateau.
Crustal shortening thickens the Earth’s crust, causing it to rise and form high plateaus. This happens when tectonic plates converge, a common cause of mountain ranges.
Thermal expansion also plays a part in forming plateaus. When the Earth’s crust heats up, it expands and pushes the surface up. This creates a flat, elevated area, typical of a plateau.
“The formation of a plateau requires one of three main tectonic processes: volcanism, crustal shortening, or thermal expansion of the underlying lithosphere.”
Understanding these tectonic processes helps us see how plateaus are formed. Plateaus are vast, flat areas on our planet. By studying these geological forces, we learn more about how our planet is shaped.
Thermal Expansion and Uplift
Ever wondered how some Earth’s highest and flattest spots, called plateaus, formed? Their creation often involves a cool process called thermal expansion and uplift.
When the Earth’s outer shell, the lithosphere, heats up fast, it expands. This happens when hot material from below rises. As it does, the surface above gets pushed up, making flat, high areas like plateaus. The East African plateau and the Ethiopian plateau are great examples of this.
The East African and Ethiopian Plateaus
The East African plateau and the Ethiopian plateau show how thermal expansion and uplift work. When the mantle beneath heats up quickly, it expands. This expansion lifts the surface above, creating vast, high plateaus in East Africa and Ethiopia.
| Plateau | Average Elevation | Area |
|---|---|---|
| East African Plateau | 1,500 – 3,000 meters | Covers much of East Africa |
| Ethiopian Plateau | 2,000 – 3,000 meters | Covers most of Ethiopia |
These plateaus show the power of forces that shape our planet. Learning about thermal expansion and uplift helps us understand these amazing landforms better.
“The formation of plateaus through thermal expansion and uplift is a testament to the dynamic and ever-changing nature of our planet.”
Crustal Shortening and Mountain Ranges
Plateaus can form through a fascinating process called crustal shortening. When tectonic plates collide, the continental crust gets compressed. This makes it thicken and uplift, creating high plateau regions.
The Altiplano in South America and the Tibetan Plateau are great examples. Their heights are impressive. The geologic structure here is different from plateaus formed by thermal expansion or volcanism.
The crust has thickened a lot due to the compressional forces. This has led to the development of towering mountain ranges. These mountains surround the elevated plateau surfaces.
Altiplano and Tibetan Plateau
The Himalayan-Tibetan orogen has absorbed a lot of crustal shortening. This happened since the Indo-Asian collision started 65-50 million years ago. Today, the convergence rate between India and Eurasia is 40-50 mm per year.
15-20 mm per year is absorbed by the Himalayan belt. And 20-30 mm per year is absorbed by deformation within the Tibetan Plateau and surrounding mountains.
Similar processes have shaped the Altiplano plateau in South America. The Andes Mountains formed due to the subduction of the Nazca and Antarctic plates under the South American plate. This has created the high, flat Altiplano landscape.
These plateaus show the powerful tectonic forces that can reshape the Earth’s surface. They transform once-flat regions into rugged, elevated landscapes over millions of years.
Volcanic Plateaus from Lava Flows
A unique type of plateau forms when flood basalts or traps cover existing land. The Columbia Plateau in the northwestern United States is a great example. It was made by volcanism linked to hot spots. This creates a flat top with deep canyons and valleys.
Columbia Plateau and Flood Basalts
The Columbia Plateau spans over 161,000 square kilometers in Washington, Oregon, and Idaho. It’s made of basalt from lava flows. These eruptions happened over 10 million years, adding over 200,000 km³ of basalt.
The volcanic activity that shaped the Columbia Plateau is tied to a hot spot. This allowed the lava and ash to travel far, making a flat surface with deep valleys.
“Lava can create new land by solidifying on the coast or emerging from beneath the water, as observed in Hawaii where lava flowing into the sea forms new land.”
Other volcanic plateaus like the Siberian Traps in Russia and the Deccan Traps in India were also formed by flood basalt eruptions. These events have greatly shaped our planet. They may have even caused mass extinctions in the past.
Combined Processes in Plateau Formation
Plateaus form through a mix of tectonic actions. These include volcanism, crustal shortening, and thermal expansion. These forces shape the high, flat landscapes we call plateaus.
The Ethiopian Plateau rises due to the heating of the lithosphere. It also has Cenozoic volcanic rocks on top. The northern Tibetan Plateau shows active volcanism and young lava flows. It also has effects from crustal shortening and thermal uplift.
Scientists have found interesting details about how plateaus are made. For example, seismic tomography shows a big part of the Colorado Plateau is falling into the mantle. Hotter asthenosphere rock replaces cooler lithosphere layers. This, along with crustal extension, has made the plateau rise thousands of feet in 6 million years.
In the Basin and Range region, the distance from Arizona and Nevada to the California coast has doubled in 17 million years. This is due to crustal extension. This process has also led to the formation of large magma bodies, like the Pine Valley Mountains and the La Sal Mountains.
The combination of tectonic processes is crucial for understanding how plateaus form and change. These processes include volcanism, thermal expansion, and crustal shortening.
“The internal forces causing stresses and chemical action on earth materials that bring about changes in the configuration of the Earth’s surface are known as geomorphic processes.”
Conclusion
Plateaus are amazing landforms that cover a big part of our planet. They are flat and elevated, shaped by tectonic processes like volcanism and crustal shortening. Learning about plateaus helps us understand the Earth’s surface changes over time.
The Tibetan Plateau and the Columbia Plateau show how different plateaus can be. Their flat surfaces come from uplift, erosion, and other geological factors. By exploring how plateaus form, we learn about the Earth’s history.
Plateaus show us the impact of plate tectonics, volcanism, and erosion. Studying them helps us understand our planet’s changes. Exploring plateaus on land and under the oceans will teach us more about Earth.
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