essay on theory of plate tectonics

ENCYCLOPEDIC ENTRY

Plate tectonics.

The theory of plate tectonics revolutionized the earth sciences by explaining how the movement of geologic plates causes mountain building, volcanoes, and earthquakes.

Earth Science, Geology, Oceanography, Geography, Physical Geography

San Andreas Fault

Tectonic plate boundaries, like the San Andreas Fault pictured here, can be the sites of mountain-building events, volcanoes, or valley or rift creation.

Photograph by Georg Gerster

Plate tectonics is a scientific theory that explains how major landforms are created as a result of Earth’s subterranean movements. The theory, which solidified in the 1960s, transformed the earth sciences by explaining many phenomena, including mountain building events, volcanoes , and earthquakes . In plate tectonics , Earth’s outermost layer, or lithosphere —made up of the crust and upper mantle—is broken into large rocky plates. These plates lie on top of a partially molten layer of rock called the asthenosphere . Due to the convection of the asthenosphere and lithosphere , the plates move relative to each other at different rates, from two to 15 centimeters (one to six inches) per year. This interaction of tectonic plates is responsible for many different geological formations such as the Himalaya mountain range in Asia, the East African Rift, and the San Andreas Fault in California, United States. The idea that continents moved over time had been proposed before the 20th century. However, a German scientist named Alfred Wegener changed the scientific debate. Wegener published two articles about a concept called continental drift in 1912. He suggested that 200 million years ago, a supercontinent he called Pangaea began to break into pieces, its parts moving away from one another. The continents we see today are fragments of that supercontinent . To support his theory, Wegener pointed to matching rock formations and similar fossils in Brazil and West Africa. In addition, South America and Africa looked like they could fit together like puzzle pieces.

Despite being dismissed at first, the theory gained steam in the 1950s and 1960s as new data began to support the idea of continental drift . Maps of the ocean floor showed a massive undersea mountain range that almost circled the entire Earth. An American geologist named Harry Hess proposed that these ridges were the result of molten rock rising from the asthenosphere . As it came to the surface, the rock cooled, making new crust and spreading the seafloor away from the ridge in a conveyer-belt motion. Millions of years later, the crust would disappear into ocean trenches at places called subduction zones and cycle back into Earth. Magnetic data from the ocean floor and the relatively young age of oceanic crust supported Hess’s hypothesis of seafloor spreading . There was one nagging question with the plate tectonics theory: Most volcanoes are found above subduction zones, but some form far away from these plate boundaries. How could this be explained? This question was finally answered in 1963 by a Canadian geologist , John Tuzo Wilson. He proposed that volcanic island chains, like the Hawaiian Islands, are created by fixed “hot spots” in the mantle. At those places, magma forces its way upward through the moving plate of the sea floor. As the plate moves over the hot spot, one volcanic island after another is formed. Wilson’s explanation gave further support to plate tectonics . Today, the theory is almost universally accepted.

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Plate Tectonics

What are tectonic plates.

Tectonic plates are large, irregular-shaped slabs of rock making up the Earth’s crust and upper mantle. They are found to float on top of a semi-liquid layer of rock called the asthenosphere.

Plate Tectonic Theory

Who Discovered Plate Tectonic Theory

Plate tectonic theory began in 1915 when Alfred Wegener proposed his theory of continental drift. Later, between the 1950s and 1970s, Wegner’s theory was updated and accepted to form the plate tectonic theory and became the modern version of continental drift.

What does the Theory of Plate Tectonics State

The theory of plate tectonics states that the Earth’s solid outer crust, the lithosphere, is divided into plates that move over the semi-liquid upper portion of the mantle, the asthenosphere .

Thus, plate tectonics is a scientific theory that deals with the large-scale motion of the plates that makes up the Earth’s lithosphere. From the deepest trench of oceans to the highest mountains, plate tectonics explains the movement of Earth’s surface in the past and present.

According to the theory of plate tectonics, the Earth’s outer shell is divided into large slabs of solid rocks, called plates, that move over the rocky inner layer above the Earth’s core, the mantle. The solid outer layer includes the crust and the upper mantle and is called the lithosphere. Below the lithosphere is a highly viscous layer called the asthenosphere. It is kept malleable by the heat deep within the Earth. It thus helps to lubricate the inner tectonic plates, allowing the lithosphere to move around.

The above theory revolutionized the Earth sciences by explaining how the movement of geologic plates causes mountain buildings, volcanoes, and earthquakes.

What are Tectonic Plates Made of

Tectonic plates are composed of the continental and oceanic crust or lithosphere.

Continental crust is composed of granitic rocks made up of relatively lightweight minerals such as quartz and feldspar. In contrast, oceanic crust is composed of basaltic rocks, which are much denser and heavier. Because continental rocks are much lighter, the crust under the continents is thicker (as much as 100 km). In contrast, the crust within the oceans is generally only about 5 km thick. Thus these massive rocks float despite their heavyweight.

What Causes Tectonic Plates to Move and Why

The underlying driving force that causes plate tectonics is convection currents or heat generated from the radioactive processes in the Earth’s mantle. According to Van der Elst, “It is kind of like a pot boiling on a stove.”

Due to the convection in the lithosphere and asthenosphere, the plates move relative to one other at different rates, between one to six inches per year. The plates above the mantle repeatedly collide, stick together, and then rip apart. Geologists named the places where segments meet and divide as plate boundaries.

How Fast Do Tectonic Plates Move

The tectonic plates move at an average rate of one to two inches (three to five centimeters) per year.

Types of Tectonic Plate Boundaries

The movement or shifting of the plates creates three types of tectonic boundaries. They are named divergent boundaries, convergent boundaries, and transform boundaries based on the unique geological feature they trigger.

1. Divergent Boundaries

It occurs when two plates slide apart, forming a narrow rift valley. Here, geysers gush out super-heated water and magma, or molten rock that rises from the mantle and solidifies into basalt, forming a new crust. In the ocean, this same process creates mid-ocean ridges. Hot magma from the mantle wells up at these ridges, forming new ocean crust, pushing the plates apart. Underwater mountains and volcanoes can rise along this seam, in some cases forming islands.

According to National Geographic, the mid-ocean ridge, the most extended mountain range on Earth, is 65,000 kilometers (40,390 miles) long and 1,500 kilometers (932 miles) wide divergent boundary.

2. Convergent Boundaries

It occurs when plates collide with one another. The collision bulges the edge of one or both plates, forming a mountain range or causing subduction of one of the plates under the other, creating a deep seafloor trench. Here, continental crust is created, and oceanic crust is destroyed as it subducts, melts, and becomes magma. Convergent plate movement also creates earthquakes and forms chains of volcanoes.

The highest mountain range, the Himalayas, was formed almost 55 million years ago when the Eurasian and Indo-Australian continental plates converged. The island of Cyprus was also formed at a convergent boundary between the African and Eurasian plates.

3. Transform Boundaries

It occurs when plates move sideways to each other. The slip-sliding motion of plate boundaries triggers many earthquakes.

California’s San Andreas Fault, where the North American and Pacific tectonic plates grind past each other, is an example of a transform boundary.

Tectonic Plates Map: Where are they Located

Earth being spherical, its tectonic plates is broken into dozens of curved sections. The border between two tectonic plates is known as a boundary. Based on the size of the plate, they are categorized into major, minor, and micro.

1. Major Plates

According to the World Atlas, there are seven major tectonic plates in all. They are listed below in order of their size.  

• Pacific Plate – 103,300,000 sq km
• North American Plate – 75,900,000 sq km
• Eurasian Plate – 67,800,000 sq km
• African Plate – 61,300,000 sq km
• Antarctic Plate – 60,900,000 sq km
• Indo-Australian Plate – 58,900,000 sq km
• South American Plate – 43,600,000 sq km

However, according to recent research published in Nature, the Indo-Australian plate has cracked over the last 10 million years, forming a separate Indian and Australian plate. These plates, if included, will increase the major plates to eight.

2. Minor and Micro Plates

There are ten minor plates and the Juan De Fuca Plate, which is a microplate. They are listed below in order of their size.  

• Somali Plate – 16,700,000 sq km
• Nazca Plate – 15,600,000 sq km
• Philippine Sea Plate – 5,500,000 sq km
• Arabian Plate – 5,000,000 sq km
• Caribbean Plate – 3,300,000 sq km
• Cocos Plate – 2,900,000 sq km
• Caroline Plate – 1,700,000 sq km
• Scotia Plate – 1,600,000 sq km
• Burma Plate – 1,100,000 sq km
• New Hebrides Plate – 1,100,000 sq km
• Juan De Fuca Plate – 250,000 sq km

Evidence of Plate Tectonics

There are multiple pieces of evidence of plate tectonics.

• Distribution of Fossils : Fossils on different continents are similar to fossils on continents that were once connected. When the continents split, different life forms developed.
• Occurrence of Earthquakes : Most continental and oceanic floor features are formed due to earthquakes. The exact pattern is explained by whether the plates are converging to create mountains or deep ocean trenches, being pulled apart to form new ocean floors or sliding past each other to create faults.
• Location of Continental and Ocean Floor Features : Distributions of rocks within the Earth’s crust, including minerals, fossil fuels, and energy reserves, are a direct result of the history of plate motions and collisions and the subsequent changes in the configurations of the continents and ocean basins.

Plate Tectonics and the Ring of Fire

The Ring of Fire also called the Circum-Pacific Belt, is a horseshoe-shaped belt around the Pacific Ocean covering a region of almost 40,000 km (24,900 miles) long and 500 km (310 miles) wide.

The region covered by the Ring of Fire includes the following plates: Pacific, Juan de Fuca, Cocos, Indian-Australian, Nazca, North American, and Philippine.

Active volcanoes and frequent earthquakes characterize it. Seventy-five percent of the Earth’s volcanoes and ninety percent of Earth’s earthquakes occur along its path, including seismic events.

Ans . No, Mars does not have plate tectonics.

Ans . Tectonic plate boundaries are associated with earthquakes and volcanoes.

Ans . We live on the lithosphere.

Ans . Alfred Wegener came up with the theory of plate tectonics.

Ans . The Pacific Plate is the largest tectonic plate.

Ans . No, the moon does not have plate tectonics.

Ans . Large Mountain chains influence the circulation of air in the atmosphere and thus can affect climate.

Ans . The main difference between continental drift and plate tectonics is that plate tectonics describes the features and movement of the Earth’s surface in the present and the past. In contrast, continental drift describes the drifting of Earth’s continents on the ocean bed. Thus, the theory of continental drift did not explain why Earth’s continents are moving.

Ans . A divergent boundary forms when tectonic plates move away from each other.

Ans . The advantages are: 1. Generate land and landforms 2. Stabilize climate over the long-run The disadvantages are: 1. It causes volcanism and earthquakes that cause a mass extinction of life and life forms on Earth. The Permian-Triassic extinction, the Triassic-Jurassic extinction, and the Late Devonian extinction are examples. 2. The hypothetical ‘snowball earth event’ in which the Earth was encased entirely in a thick layer of ice is thought to be the likely cause of the movement of tectonic plates.

• What is plate tectonics?  – Livescience.com
• Plate Tectonics – Ucmp.berkeley.edu
• Plate Tectonics – Pnsn.org
• Plate Tectonics – Nationalgeographic.org
• How Many Tectonic Plates Are There? – Worldatlas.com
• Understanding Plate Tectonic Theory – Earthquakeauthority.com

Article was last reviewed on Friday, February 17, 2023

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When the concept of seafloor spreading came along, scientists recognized that it was the mechanism to explain how continents could move around Earth’s surface. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics.

Watch this video about continental drift and the mechanism of seafloor spreading create plate tectonics.

EARTH’S TECTONIC PLATES

Seafloor and continents move around on Earth’s surface, but what is actually moving? What portion of the Earth makes up the “plates” in plate tectonics? This question was also answered because of technology developed during war times – in this case, the Cold War. The plates are made up of the lithosphere.

During the 1950s and early 1960s, scientists set up seismograph networks to see if enemy nations were testing atomic bombs. These seismographs also recorded all of the earthquakes around the planet. The seismic records could be used to locate an earthquake’s epicenter , the point on Earth’s surface directly above the place where the earthquake occurs.

Earthquake epicenters outline the plates. Mid-ocean ridges, trenches, and large faults mark the edges of the plates, and this is where earthquakes occur (figure 1).

The lithosphere is divided into a dozen major and several minor plates (figure 2). The plates’ edges can be drawn by connecting the dots that mark earthquakes’ epicenters. A single plate can be made of all oceanic lithosphere or all continental lithosphere, but nearly all plates are made of a combination of both.

Movement of the plates over Earth’s surface is termed plate tectonics . Plates move at a rate of a few centimeters a year, about the same rate fingernails grow.

HOW PLATES MOVE

If seafloor spreading drives the plates, what drives seafloor spreading? Picture two convection cells side-by-side in the mantle, similar to the illustration in figure 3.

• Hot mantle from the two adjacent cells rises at the ridge axis, creating new ocean crust.
• The top limb of the convection cell moves horizontally away from the ridge crest, as does the new seafloor.
• The outer limbs of the convection cells plunge down into the deeper mantle, dragging oceanic crust as well. This takes place at the deep sea trenches.
• The material sinks to the core and moves horizontally.
• The material heats up and reaches the zone where it rises again.

Check out this animation of mantle convection and watch this video:

PLATE BOUNDARIES

Plate boundaries are the edges where two plates meet. Most geologic activities, including volcanoes, earthquakes, and mountain building, take place at plate boundaries. How can two plates move relative to each other?

• Divergent plate boundaries : the two plates move away from each other.
• Convergent plate boundaries : the two plates move towards each other.
• Transform plate boundaries : the two plates slip past each other.

The type of plate boundary and the type of crust found on each side of the boundary determines what sort of geologic activity will be found there.

Divergent Plate Boundaries

Plates move apart at mid-ocean ridges where new seafloor forms. Between the two plates is a rift valley. Lava flows at the surface cool rapidly to become basalt, but deeper in the crust, magma cools more slowly to form gabbro. So the entire ridge system is made up of igneous rock that is either extrusive or intrusive. Earthquakes are common at mid-ocean ridges since the movement of magma and oceanic crust results in crustal shaking. The vast majority of mid-ocean ridges are located deep below the sea (figure 4).

Check out these animations:

• Divergent plate boundary at mid-ocean ridge
• Divergent plate boundary

Can divergent plate boundaries occur within a continent? What is the result? Incontinental rifting (figure 5), magma rises beneath the continent, causing it to become thinner, break, and ultimately split apart. New ocean crust erupts in the void, creating an ocean between continents.

Convergent Plate Boundaries

When two plates converge, the result depends on the type of lithosphere the plates are made of. No matter what, smashing two enormous slabs of lithosphere together results in magma generation and earthquakes.

Ocean-Continent

When oceanic crust converges with continental crust, the denser oceanic plate plunges beneath the continental plate. This process, called subduction , occurs at the oceanic trenches (figure 6). The entire region is known as a subduction zone . Subduction zones have a lot of intense earthquakes and volcanic eruptions. The subducting plate causes melting in the mantle. The magma rises and erupts, creating volcanoes. These coastal volcanic mountains are found in a line above the subducting plate (figure 7). The volcanoes are known as a continental arc .

The movement of crust and magma causes earthquakes. Look at this map of earthquake epicenters at subduction zones. This animation shows the relationship between subduction of the lithosphere and creation of a volcanic arc.

The volcanoes of northeastern California—Lassen Peak, Mount Shasta, and Medicine Lake volcano—along with the rest of the Cascade Mountains of the Pacific Northwest are the result of subduction of the Juan de Fuca plate beneath the North American plate (figure 8). The Juan de Fuca plate is created by seafloor spreading just offshore at the Juan de Fuca ridge.

If the magma at a continental arc is felsic, it may be too viscous (thick) to rise through the crust. The magma will cool slowly to form granite or granodiorite. These large bodies of intrusive igneous rocks are called batholiths , which may someday be uplifted to form a mountain range (figure 9).

Ocean-Ocean

When two oceanic plates converge, the older, denser plate will subduct into the mantle. An ocean trench marks the location where the plate is pushed down into the mantle. The line of volcanoes that grows on the upper oceanic plate is an island arc . Do you think earthquakes are common in these regions (figure 10)?

Check out this animation of an ocean continent plate boundary.

Continent-Continent

Continental plates are too buoyant to subduct. What happens to continental material when it collides? Since it has nowhere to go but up, this creates some of the world’s largest mountains ranges (figure 11). Magma cannot penetrate this thick crust so there are no volcanoes, although the magma stays in the crust. Metamorphic rocks are common because of the stress the continental crust experiences. With enormous slabs of crust smashing together, continent-continent collisions bring on numerous and large earthquakes.

Check out this short animation of the Indian Plate colliding with the Eurasian Plate.

Watch this animation of the Himalaya rising.

The Appalachian Mountains are the remnants of a large mountain range that was created when North America rammed into Eurasia about 250 million years ago.

Transform Plate Boundaries

Transform plate boundaries are seen as transform faults , where two plates move past each other in opposite directions. Transform faults on continents bring massive earthquakes (figure 12).

California is very geologically active. What are the three major plate boundaries in or near California (figure 13)?

• A transform plate boundary between the Pacific and North American plates creates the San Andreas Fault, the world’s most notorious transform fault.
• Just offshore, a divergent plate boundary, Juan de Fuca ridge, creates the Juan de Fuca plate.
• A convergent plate boundary between the Juan de Fuca oceanic plate and the North American continental plate creates the Cascades volcanoes.

A brief review of the three types of plate boundaries and the structures that are found there is the subject of this wordless video.

EARTH’S CHANGING SURFACE

Geologists know that Wegener was right because the movements of continents explain so much about the geology we see. Most of the geologic activity that we see on the planet today is because of the interactions of the moving plates.

In the map of North America (figure 14), where are the mountain ranges located? Using what you have learned about plate tectonics, try to answer the following questions:

• What is the geologic origin of the Cascades Range? The Cascades are a chain of volcanoes in the Pacific Northwest. They are not labelled on the diagram but they lie between the Sierra Nevada and the Coastal Range.
• What is the geologic origin of the Sierra Nevada? (Hint: These mountains are made of granitic intrusions.)
• What is the geologic origin of the Appalachian Mountains along the Eastern US?

Remember that Wegener used the similarity of the mountains on the west and east sides of the Atlantic as evidence for his continental drift hypothesis. The Appalachian mountains formed at a convergent plate boundary as Pangaea came together (figure 15).

Before Pangaea came together, the continents were separated by an ocean where the Atlantic is now. The proto-Atlantic ocean shrank as the Pacific ocean grew. Currently, the Pacific is shrinking as the Atlantic is growing. This supercontinent cycle is responsible for most of the geologic features that we see and many more that are long gone (figure 16).

This animation shows the movement of continents over the past 600 million years beginning with the breakup of Rodinia.

LESSON SUMMARY

• Plates of lithosphere move because of convection currents in the mantle. One type of motion is produced by seafloor spreading.
• Plate boundaries can be located by outlining earthquake epicenters.
• Plates interact at three types of plate boundaries: divergent, convergent and transform.
• Most of the Earth’s geologic activity takes place at plate boundaries.
• At a divergent boundary, volcanic activity produces a mid ocean ridge and small earthquakes.
• At a convergent boundary with at least one oceanic plate, an ocean trench, a chain of volcanoes develops and many earthquakes occur.
• At a convergent boundary where both plates are continental, mountain ranges grow and earthquakes are common.
• At a transform boundary, there is a transform fault and massive earthquakes occur but there are no volcanoes.
• Processes acting over long periods of time create Earth’s geographic features.

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Contributors and Attributions

Original content from Kimberly Schulte (Columbia Basin College) and supplemented by Lumen Learning . The content on this page is copyrighted under a Creative Commons Attribution 4.0 International license.

Home — Essay Samples — Environment — Earthquake — Plate Tectonics Theory

Plate Tectonics Theory

• Categories: Earthquake Plate Tectonics

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Words: 417 |

Published: Jan 4, 2019

Words: 417 | Page: 1 | 3 min read

Works Cited

• Dietz, R. S., & Holden, J. C. (1970). Plate tectonics and sedimentation. Elsevier.
• Oreskes, N. (2001). Plate tectonics: an insider's history of the modern theory of the Earth. Westview Press.
• Palmer, D. (1983). The origin of continents and oceans. John Wiley & Sons.
• Press, F., & Siever, R. (1974). Earth. W.H. Freeman.
• Tarbuck, E. J., & Lutgens, F. K. (2011). Earth science. Prentice Hall.
• Turcotte, D. L., & Schubert, G. (2014). Geodynamics. Cambridge University Press.
• van der Pluijm, B. A., & Marshak, S. (2004). Earth structure: an introduction to structural geology and tectonics. WW Norton & Company.
• Wegener, A. (1966). The origin of continents and oceans (J. Biram, Trans.). Methuen & Co.
• Wicander, R., & Monroe, J. S. (2016). Historical geology. Cengage Learning.
• Wilson, J. T. (1963). A possible origin of the Hawaiian Islands. Canadian Journal of Physics, 41(6), 863-870.

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Plate Tectonics Pioneer Challenges the Way Earth Works

Lynn Sykes with an old-fashioned rotating-drum seismograph at Lamont-Doherty Earth Observatory in 2015. Image Courtesy Lamont-Doherty Earth Observatory.

As an undergrad at MIT in the 1950s, Lynn Sykes ’59, SM ’60 became interested in the theory of continental drift, which proposed that the world’s great landmasses had wandered across Earth over time. The theory had been proposed most notably by Alfred Wegener in the early 20th century, but it was largely considered outlandish by the scientific community. “I was told that decent graduate students didn’t work on such crazy ideas,” he remembers. But just a few years later, he would make a discovery that would help prove the theory’s legitimacy.

It was recognized right then and there, and by a number of people who previously thought it could not and did not exist.

At MIT, Sykes was inspired by a first-year geology course with the late professor Bill Brace ’46, ’49, PhD ’53 and later by MIT’s partnership with Woods Hole Oceanographic Institute to work in the field of oceanic seismology. After earning a bachelor’s and master’s in geology and geophysics from the Institute, he pursued his doctorate at Columbia University, where he studied deep-ocean earthquakes. It was there that he discovered a curious phenomenon in the South Pacific—a line of earthquake activity along a 600-kilometer-long fracture zone that had never been observed before. Sykes discovered a similar phenomenon in the Atlantic north of Iceland. They turned out to be the first evidence of a transform fault, a feature proposed by Canadian geophysicist John Tuzo Wilson in which seismic activity occurs in a rupture between two ridges, leading the seafloor to spread and continents to move. 

Sykes presented his data at a conference in 1966, showing that continental drift, now known as plate tectonics, was occurring. “It was recognized right then and there, and by a number of people who previously thought it could not and did not exist,” says Sykes, who is now recognized as one of the progenitors of the concept. That claim to fame is just one instance in which Sykes has tilted against conventional wisdom in his long career as a seismologist. 

Even as a child, Sykes began to understand how attention to data could prevail against the herd. He recalls an instance in which his father, a weather forecaster, predicted a bout of extreme cold one Thanksgiving weekend. In 10th grade, Sykes had another formative experience when he received an award for an essay on the then-nascent theory of global warming. “It led me to believe that there were important societal things science could contribute to, and I wanted to be a part of that,” he says.

Sykes became a professor at Columbia’s Lamont-Doherty Earth Observatory after earning his PhD and turned his attention toward monitoring seismic waves from underground nuclear testing. In the late 1960s, many doubted that underground nuclear tests could be distinguished from earthquakes, making a treaty on underground testing impossible to enforce. Sykes proved naysayers wrong by helping show differences in their seismic signatures. “People said there were numerous ways Russians could cheat, and along with others, I was able to show that was not the case,” says Sykes, who testified before Congress and traveled to Moscow for the signing of the Threshold Test Ban Treaty in 1974. 

He continued his research over the decades, showing that it was possible to detect even tiny seismic waves from nuclear tests, leading to the Comprehensive Nuclear-Test-Ban Treaty, banning all nuclear explosions on Earth, in 1996. “I was happy I continued to work on this for decades,” Sykes says.

Now 87, Sykes is still challenging ideas about the way Earth works. This February, he published a controversial paper about earthquakes along California’s San Andreas Fault, arguing that events such as the 1989 Loma Prieta quake that devastated San Francisco could have been predicted from signs occurring decades in advance. “In the future, knowing those signs can help us take steps to strengthen sites years ahead of time,” he argues. That idea runs counter to current beliefs that the locations of future earthquakes are  impossible to predict . For Sykes, he says it’s not about—and has never been about—being right or debating people, he just follows the data to help solve problems. “I think that these are important problems, that’s what I emphasize.”

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74 Plate Tectonics Essay Topic Ideas & Examples

🏆 best plate tectonics topic ideas & essay examples, 👍 good essay topics on plate tectonics, 📌 simple & easy plate tectonics essay titles, ❓ essay questions about plate tectonics.

• Plate Tectonics and Lithosphere Development This move causes the destruction and the rupture of the continental blocks in the tension areas, their horizontal displacement and the young crust formation in the bed of newly formed oceans; accumulation, accompanied by thrust, […]
• Linking Plate Tectonics and Continental Drift Plate tectonics is a hypothetical movement of earth’s crust plates: a theory that ascribes continental drift, volcanic and seismic activity, and the formation of mountain belts to moving plates of the Earth’s crust supported on […]
• Plate Tectonics Theory and Its Development When the asthenosphere reaches the lithosphere, it turns aside, “lifting and cracking the crust” to create the plate edges. The movement of plates is generated by gravity.
• Plate Tectonics and Volcanic Activity The result of subduction is the older oceanic plates’ sinking to the mantle to form volcanoes as weak spots there because the magma breaks the ocean floor.
• Ocean-Plate Tectonics and Geology Bathymetry of the ocean seafloor refers to the measurement of how deep the sea is in relation to the sea level.
• Plate Tectonics Theory and Features For instance, where there are volcanic eruptions during the convergence of the plates, magma solidifies on top of the oceanic crust to form a hard surface on the ocean.
• Plate Tectonics, Volcanism, Earthquakes and Rings of Fire Plate tectonics has led to the separation of the sea floor over the years and the earth is composed of seven tectonic plates according to the available geological information.
• The Types of Plate Tectonics Essay The movement of these plates is facilitated by the fact that they float on the Earth’s molten magma on the region called asthenosphere, which lies, below lithosphere.
• Alfred Wegener and the Exploration of Plate Tectonics
• Can Disasters That Occur Due to Plate Tectonics Be Prevented
• Plate Tectonics and the Fossil History of Panama
• How Plate Tectonics Theory Helps Our Understanding of Seismic and Volcanic Events
• Geography: Plate Tectonics and Great Global Rift
• Impact of Plate Tectonics on Continental Drift
• The Connection Between Plate Tectonics and Formation of Mineral Ore Deposits
• Plate Tectonics and Its Impact on the Earth
• Description of the Continental Drift Theory and Plate Tectonics Theory
• Plate Tectonics and Related Hazards in Southern California
• The Evidence That Supports the Theory of Continental Drift and Plate Tectonics
• Plate Tectonics and Landform Processes
• The Most Active Area of Our Plate Tectonics
• Plate Tectonics: Theoretical Aspects and the Geological
• The San Andreas Fault and Its Role in Plate Tectonics and Earthquake Prediction
• What Biological Evidence Supports Plate Tectonics
• The Theory of Plate Tectonics and the Three Types of Plate Boundaries
• The Discovery of Plate Tectonics and the Awareness of Sea Floor Spreading
• The Evolution of Plate Tectonics in Europe
• The Importance of Plate Tectonics in Predicting the Past
• An Introduction to the Geology, Plate Tectonics in Twentieth Century
• An Analysis of the Plate Tectonics Around the Globe
• An Overview of the Theories Explaining the Plate Tectonics of the Earth
• The Scientific Theories of the Plate Tectonics in the Book “Journey to the Center of the Earth”
• The Concept of Plate Tectonics in Geological Activities
• The Impact of Plate Tectonics on the Natural Disasters on the West Coast
• The Importance of the Continental Drift Theory to the Development of Plate Tectonics
• What Features of the Ocean Floor Provide Evidence of Plate Tectonics
• What Convection Currents Give Evidence for Wegener’s Theory of Plate Tectonics
• Plate Tectonics and Landforms on Earth Surfaces
• The Effect of Plate Tectonics on the Caribbean Region
• The Role of the Knowledge of Plate Tectonics
• Tectonic Plates and Their Effects on the Physical Face of the Earth
• Convergent Plate Tectonics: Why Is the Earth Getting Larger
• The Theory of Plate Tectonics and Earth’s Crust Displacement
• Plate Tectonics: Theoretical Aspects and the Geological History of North America
• What Are Plate Tectonics and Ocean Currents Influence Climate Change
• What Are the Different Types of Plate Tectonics Boundaries
• Plate Tectonics Types: Divergent, Convergent, and Transform Plates
• Plate Tectonics Boundaries and Tectonic Settings of Volcanism
• Is Plate Tectonics a Natural Phenomenon or an Artificial One?
• What Can Happen to Plate Tectonics if Humans Intervene in the Process?
• How Does the Wilson Cycle Relate to Plate Tectonics?
• How Does the Plate Tectonics Theory Explains the Existence of Fossil Marine Life?
• How Does Radioactive Dating Help Provide Evidence for the Movement of Plate Tectonics?
• Are All Continental Coastlines Plate Boundaries on the Topic of Plate Tectonics?
• What Role Does Plate Tectonics Play in Global-Scale Climate Change?
• Why Is the Theory of Plate Tectonics Important?
• Who Contributed to the Theory of Plate Tectonics?
• What Is the Difference Between Plate Tectonics and Plate Boundaries?
• What Are the Plates of Plate Tectonics Made up Of?
• How Was the Theory of Plate Tectonics Developed?
• How Does the Theory of Plate Tectonics Help to Explain the World Distribution of Earthquake and Volcanic Zones?
• Are There Plate Tectonics on the Moon?
• When Was the Theory of Plate Tectonics Accepted?
• How Do Plate Tectonics Support Continental Drift?
• What Landforms Are Created by Plate Tectonics?
• Why Are Magnetic Patterns Important Evidence for Plate Tectonics?
• How Does Fossil Evidence Support the Theory of Plate Tectonics?
• Why Does Earth Have Plate Tectonics and Continents?
• How Has the Theory of Plate Tectonics Changed Over Time?
• Who Discovered Plate Tectonics?
• What Biological Evidence Supports Plate Tectonics?
• How Plate Tectonics Can Help Our Understanding of the Distribution of either Earthquakes or Volcanic Eruption?
• How Does the Plate Tectonics Theory Help Explain the Existence of Fossilized Marine Life in Rocks Atop the Ural Mountains?
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Scientists offer new theory on the origin of plate tectonics

( NewsNation ) — Scientists have long wondered why the Earth has a broken, rocky surface made up of huge plates that crash into each other. A new theory says it’s connected to the Mars-sized object that crashed into Eart about 4.5 billion years ago, which created our moon.

The authors of a new study published in Geophysical Research Letters believe that when the collision occurred, pieces of that huge object stayed behind in the form of mysterious blobs under the earth’s surface. Debris from the collision formed the moon.

Two blobs, formally known as large low-velocity provinces (LLVPs), consist of material that’s different than the surrounding earth’s mantle. One is under the African continent, another under the Pacific Ocean. Both are twice the size of the moon.

Those blobs, the theory goes, created plate tectonics – the geologic phenomenon that fuels earthquakes and volcanoes, which allow life to flourish.

“The giant impact is not only the reason for our moon if that’s the case, it also set the initial conditions of our Earth,” California Institute of Technology geoscientists and study co-author Qian Yuan told The Washington Post.

The new theory also shines a light on previous theories – or, in the case of UCLA professor T. Mark Harrison, a “non-theory.” His recent paper entitled “We Don’t Know When Plate Tectonics Began” points out geochemical inconsistencies that cast doubt on the giant impact theory itself.

“The best thing I can tell people is that my generation … couldn’t solve arguably the most interesting question left in science, which is how and under what conditions did life emerge,” he wrote.

For the latest news, weather, sports, and streaming video, head to NewsNation.