The hypothesis of continental drift led to plate tectonicsa theory that explains many processes in earth. Africa coloring map of countries i put this in a pdf and in printing options i selected poster and out it at. Plate tectonics thus provides the big picture of geology. We cannot make a mathematical nor real model of plate tectonics. The fixists edit hans stille and leopold kober opposed the idea of continental drift and worked on a fixist 38 geosyncline model with earth contraction playing a key role in the formation of orogens. I think the visual of the plates moving would assign in understanding of plate tectonics. Plate tectonics the theory of plate tectonics has only emerged and matured as a widely accepted theory since the 1960s. How does paleomagnetism support the plate tectonics theory. Putting these two words together, we get the term plate tectonics, which refers to how the earths surface is built of plates. The word tectonics comes from the greek root to build.
The rock at earths surface forms a nearly continuous shell around earth called the lithosphere. Central to the theory of plate tectonics is the concept of. As with any new theory or discovery, there are those who will resist it and those who embrace it. The plate tectonics gizmo shows a crosssection, or side view, of earth. Plate tectonics is the most important concept in modern geology. The geological information yields a mean life span of 2ga for the. Plate tectonics, theory dealing with the dynamics of earths outer shell that revolutionized earth sciences by providing a uniform context for understanding mountainbuilding processes, volcanoes, and earthquakes as well as the evolution of earths surface and reconstructing its. But through wegeners persistence, perseverance, and openmindedness to the contributions of others, the theory of continental drift evolved into the widely accepted theory today of plate tectonics. The theory of plate tectonics grew out of earlier hypotheses and observations. As plates move, the new crust gradually moves away from the ridge.
Continental drift is the theory that the earths continents have moved over geologic time relative to each other, thus appearing to have drifted across the ocean bed. In the early 1900s alfred wegener proposed the continents were drifting. Looking at the information you compiled in your chart above, explain one way the theory of plate tectonics can relate to engineering. History of plate tectonics plate tectonic theory had its beginnings in 1915 when alfred wegener proposed his theory of continental drift. Plate tectonics is the theory that explains the global distribution of geological phenomena. Some figures have been modified to enhance legibility at screen resolutions. Students gather evidence to explain the theory of plate tectonics. Discover the science behind earthquakes and volcanoes with this worksheet on plate tectonics. Origins of plate tectonic theory earth science visionlearning. Plate tectonic theory arose out of the hypothesis of continental drift. Principally it refers to the movement and interaction of the earths lithosphere. It explains plate tectonics as the driving force behind ongoing changes on earth. Plate tectonics is a theory developed in the late 1960s, to explain how the outer.
Once every 200,000 years, the earths magnetic field reverses polarity. When the concept of seafloor spreading came along, scientists recognized that it was the mechanism to explain how continents could move around earths surface. Plate tectonics defines the movements and features of the earths surface now and in the past. Subduction zones are where mountainbuilding orogeny occurs 6. And yet, the theory of plate tectonics represents a fairly young science. Critique and interpret major types of evidence supporting the theory of plate tectonics. The original definition of plate tectonics has recently been modified to include a description of the driving force as a theory of global tectonics powered by subduction in which the lithosphere is divided into a mosaic of plates, which move on and sink into weaker ductile asthenosphere. In the 1960s, scientists discovered the plate edges through magnetic surveys of the. New ocean crust is created along midocean ridges 4. New oceanic crust is formed through magma rising through the gap and cooling. The theory, or idea, of plate tectonics says that earth s outer layer is made up of large, moving pieces called plates. The father of plate tectonics, alfred wegener proposed continental drift in 1912, but was ridiculed by fellow scientists. Developed from the 1950s through the 1970s, plate tectonics is the modern version of continental drift, a theory first proposed by scientist alfred wegener in 1912.
The theory of plate tectonics explains the relative movement of crustal plates that are juxtaposed with each other to form an interlocking pattern of plate boundaries, oceanic trenches, mountain ranges, etc. Under the plates is a weaker layer of partially melted rock. Heat from the mantle is the source of energy driving plate tectonics. Though the faces of the earth did not include much original work, seuss demonstrated a great ability to synthesize work into the bigger picture. Top this article has been rated as topimportance on the. Plate tectonics from the late latin tectonicus, from the greek. If you would like to participate, you can choose to edit this article, or visit the project page for more information. The speculation that continents might have drifted was first put forward by abraham ortelius in 1596. For more information on how to use these and other tools, see appendix a. In geologic terms, a plate is a large, rigid slab of solid rock. Even though the theory of plate tectonics is now widely accepted by the scientific community, aspects of the theory are still being debated today. Plate tectonics theory history plate tectonics, plate. Word parts prefixes many scientific words are made up of word parts that come from latin and greek.
Plate tectonics simple english wikipedia, the free encyclopedia. The theory of continental drift was the first step toward plate tectonic theory, which became the foundation upon which modern geology is built. Above the cross section is a birdseye view of the same location. Plate tectonics describes the distribution and motion of the plates. Heat flow and movement of material within earth cause sections of earths crust to move. B this article has been rated as bclass on the projects quality scale. You will recall from a previous chapter that there are three major layers crust, mantle, core within the earth that are. A brief introduction to alfred wegeners theory of continental drift, which would lay the groundwork for the development of plate tectonic theory, which essentially explains the geology of the. Plate tectonics birth of a theory wegener cartoon pictures pdf 881 kb this activity is the first in a sequence of two activities. The theory of plate tectonics was advanced in the 1960s and 1970s to generate new information about the earths ancient magnetism, the nature of the ocean floor, the flow of heat from the earths interior, and earthquake and volcanic distribution with the main aim of explaining how the earth works. Specific contributions to plate tectonic theory or geophysics. However, after a less than a year since internet publication of the brochure, i decided to change its title to the one that better reflects its content, i. They also look at how volcanoes and earthquakes are explained by tectonic plate movement, and how engineers use this information.
This plate motion causes them to collide, pull apart, or scrape. Additional information for teachers background information year 9, unit 2. The lithosphere is divided into plates, some of which are very large and can be entire continents. Exactly how this works is still a matter of debate. Jul 24, 2019 continental drift was a revolutionary scientific theory developed in the years 19081912 by alfred wegener 18801930, a german meteorologist, climatologist, and geophysicist, that put forth the hypothesis that the continents had all originally been a part of one enormous landmass or supercontinent about 240 million years ago before breaking apart and drifting to their current locations. Continental drift, sea floor spreading and plate tectonics. The theory of plate tectonics describes how the plates move, interact, and change the physical landscape. The structure of the earth, plate tectonics and landforms. Plate tectonics is the central unifying theory for geology and geophysics. Frisch and meschede and blakey answer all these questions and more through the presentation and explanation of the geodynamic processes upon which the theory of continental drift is based and which have led to the concept of plate tectonics.
Two scientific advances in the mid20th century resulted in information critical to acceptance of continental drift and plate tectonic theory. The lithosphere is divided into plates, some of which are very large and can be entire continents heat from the mantle is the source of energy driving plate tectonics. As constructive plates add new rock to the surface, this could and magnetic minerals within the rocks aligns itself with the direction of the earths magnetic field. This theory states that the earths outermost layer is fragmented into a dozen or more large and small solid slabs called tectonic lithospheric plates. Plate tectonics is an earth sciences topic that attracts a good deal of interest, given that it a topic very often featured in popular science programmes on tv and radio. The theory of plate tectonics grew out of earlier hypotheses and observations collected during exploration of the rocks of the ocean floor. Paleomagnetism the history of the earths magnetic field. We have a hypothesis of the general mechanics, but there might be pieces of data that do not fit the overall principle.
At divergent boundaries in the oceans, magma from deep in the earths mantle rises toward the surface and pushes apart two or more plates. Plate tectonicsthe unifying theory of geology geology u. Plate tectonics is a theory of geology developed to explain the phenomenon of continental drift and is currently the theory accepted by the vast majority of scientists working in this area. It would be a good worksheet for selfdirected learning either given to students before or after the lesson about types of plate movement. This includes the formation, movement, collision and destruction of plates and the resulting geological events such as seismicity, volcanism, continental drift, and. The earth surface has continuously been changing ever since it was formed, especially regarding the geomorphological and geological phenomena. The theory of plate tectonics worksheet teachengineering. The theory of plate tectonics states that the earths outermost layer is fragmented into a dozen or more large and small plates that are moving. You will recall from a previous chapter that there are three. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. Plate tectonics, theory dealing with the dynamics of earths outer shell that revolutionized earth sciences by providing a uniform context for understanding mountainbuilding processes, volcanoes, and earthquakes as well as the evolution of earths surface and reconstructing its past continents and oceans.
This module describes how the work of alfred wegener, harry hess, and others led to our understanding of plate tectonics. Central to the theory of plate tectonics is the concept of internal rigidity of tectonic plates together with eulers theo rem, which allows us to model the relative motion of plates. Small pieces of crust terranes are important in building up. This may result in earthquakes, volcanic eruption, and the creation of mountains and ocean basins. Continental drift and the development of plate tectonic theory. The earths crust is divided into plates which are moved in various directions. The theory of plate tectonics geology lumen learning. Dec 19, 2017 plate tectonics is now the widely accepted theory that earths crust is fractured into rigid, moving plates. Working in pairs, students think like engineers and connect what they. Describe the basic characteristics of arths three layers. Contractional theory, continental drift and plate tectonics. Most earthquakes and volcanoes occur along plate boundaries 3. The earth is the only planet known to currently have plate tectonics. Plate tectonics simple english wikipedia, the free.
Directed theory plate tectonics answers free pdf file. Plate tectonics is part of wikiproject geology, an attempt at creating a standardized, informative, comprehensive and easytouse geology resource. Using the online resources at the earthquakes living lab, students examine information and gather evidence supporting the theory. Seafloor spreading helps explain continental drift in the theory of plate tectonics.
Ocean basinsoceanic crust are continually being created and destroyed through tectonic processes. Plate tectonics by combining the sea floor spreading theory with continental drift and information on global seismicity, the new theory of plate tectonics became a coherent theory to explain crustal movements. Plate tectonics is a good example of how the science community collects evidence and then continuously tests the theory. The evolution of plate tectonics philosophical transactions. Seafloor spreading occurs at divergent plate boundaries which subsequently create midocean ridges.
The theory of plate tectonics activityworksheet 3 volcanoes 8. Plate tectonics information and facts national geographic. Plate tectonics is the unifying theory of geology and. The concept was independently and more fully developed by alfred wegener in 1912, but his theory was rejected by many for. It would take another 50 years for the concept to be accepted.
As the overlying plate lifts up, it also forms mountain ranges. The theory of plate tectonics explains all this, including the movement of the continents, better than wegeners theory. First, the topography of the ocean floor was mapped in great detail during and after world war ii. This section will introduce you to the concept of plate tectonics, how it works, why it is important and how it is shaping the world today. This is a worksheet about plate tectonics, which students can read and write down the correct plate boundary in the appropriate box. These convergent boundaries also occur where a plate of ocean dives, in a process called subduction, under a landmass.
The plates are constantly moving over this weaker layer. Wegener proposed that the continents plowed through crust of ocean basins, which would explain why the outlines of many coastlines like south america and africa look like they fit together like a puzzle. The earth surface has continuously been changing ever since it was formed, especially regarding. Usgs information services box 25286, building 810 denver federal center denver, co 80225 3032024700. Suess is credited for generating many of the concepts that led to the theory of plate tectonics and paleogeography. Observations that led to the development of plate tectonic theory. Plate tectonics has proven to be as important to the earth sciences as the discovery of the structure of the atom was to physics and chemistry and the theory of evolution was to the life sciences. Plate tectonicsthe unifying theory of geology geology.
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