Continental drift and plate tectonics free download as powerpoint presentation. Plate tectonics and continental drift tectonics is the study of the orig in and arran gement o f earths stru ctural fea tures w hich include not only folds and faults but also continents, mountains, and earthquake regions. Early case for continental drift glossopteris plant, lystrosaurus and cynognathus animals fossils found on all five continents mesosaurus reptile fossils found in brazil and south africa only. Learn plate tectonics continental drift questions with free interactive flashcards. In some places, it slides under the continental crust and melts into the. What effect did con0nental drift have on distribu0on and factors of ecological importance. Alfred wegener and continental drift it was not until 1912 that the idea of moving continents was seriously considered as a fullblown scientific theory called continental drift introduced in two articles published by a 32yearold german meteorologist named alfred lothar wegener alfred lothar wegener 18801930 earned a.
The plain mans guide to plate tectonics sciencedirect. According to the theory, earth has a rigid outer layer, known as the lithosphere, which is typically about 100 km 60 miles thick and overlies a plastic moldable, partially molten layer called the asthenosphere. For nearly half a century, from the 1920s to the 1960s, most scientists paid little attention to the idea of continental drift. Plate tectonics plate tectonics is the unifying theory of geology and revolutionized geology cornerstone of earthsystem approach. Concerning the theory of plate tectonics, i am more knowledgeable than the average person on the street, but i am greatly humbled by the vast expanse of what plate tectonics involves and the depth of knowledge that geologist have attained. In the 1960s, geology was transformed by the paradigm of plate tectonics. In the 20th century, researchers realized that the earths crust is not one piece, but is made up of many huge tectonic plates upon which the continents ride. Mar 17, 2016 in the 20th century, researchers realized that the earths crust is not one piece, but is made up of many huge tectonic plates upon which the continents ride. Wegeners continental drift meets wilsons plate tectonics. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. Alfred wegener, in the first three decades of this century, and dutoit in the 1920s and 1930s gathered evidence that the continents had moved. All continents were once connected as one large landmass now called pangaea. Since the development of the theory, geologists have had to reexamine almost every aspect of.
Continental drift section 1 plate tectonics underlined words and phrases are to be filled in by students on the a. Where else are the same or similar organisms found. This mantle convection concept has been appearing in many geology textbooks since then, but hardly treated seriously. Choose from 500 different sets of continental drift theory plate tectonics flashcards on quizlet. Choose from 500 different sets of plate tectonics continental drift questions flashcards on quizlet. Continental drift the first step in the scientific method begins with making observations 102 years ago, in 1912, alfred wegener made observations about the similarities of different continents based on his observations, and using the scientific method, he formulated a hypothesis. It was not until 1912 that the idea of moving continents was seriously considered as a fullblown scientific theory called. Continental drift and plate tectonics kaiserscience. The concept was independently developed by german geologist alfred wegener in 1912.
On the driving forces of plate tectonics geophysical journal. The theory has caused a revolution in the way we think about the earth. Ever since the first global maps were drawn following the great voyages of discovery of the 15th and 16th centuries, it has been realised that the coastline geography of the continents on either side of the atlantic ocean form a pattern that can be fitted back together. The hypothesis asserts that the continents consist of. Continental drift and plate tectonics plate tectonics. Continental drift and plate tectonics are two theories explaining the geological evolution of the earth, specifically its crust. Sea floor spreading, continental drift and lithosphere sinking with an asthenosphere at melting point. Animation of sea floor spreading worldwide earthquake patterns help us know where the edges of plates are located the earths plates wegener 18801930 continental drift was wegeners theory that all continents had once been joined together in a single landmass and have drifted apart since.
The lithosphere is divided into moving segments that change. If you continue browsing the site, you agree to the use of cookies on this website. Plate tectonics and the continental drift theory youtube. Continental drift is a theory first presented by abraham ortelius abraham ortels in 1596. Pdf a mantle convection perspective on global tectonics. Learn continental drift theory plate tectonics with free interactive flashcards. This is consistent with the previously considered evidence for continental drift and validates the hypotheses of wegener and du toit. In other words, plate tectonics explains continental drift, among other things. Bringing together a large mass of geologic and paleontological data, wegener postulated that throughout most of geologic time there was only one continent, which he called pangea, and the breakup of this continent heralded earths current continental. They based their idea of continental drift on several lines of evidence. Subduction zone oceanic crust is heavier than continental crust. Continental drift theory continental drift is the hypothesis that all the continents had once been joined together in a single landmass. Plate tectonicscontinental drift and mountain building article pdf available in bulletin of volcanology 741.
Explain the theory of continental drift, and how it. Is the idea that the continents are slowly drifting further away from each other. Plate tectonics is the theory that unified the old continental drift theory and the concept of sea floor speading. Video showing how convection cells inside the earth move tectonic plates on the earths surface. Importantly, drift paths recorded by paleomagnetism culminate in the assembly of a supercontinent during the late paleozoic. According to the theory of continental drift, the world was made up of a single continent through most of geologic time. Subduction zones are where mountainbuilding orogeny occurs 6. The plate tectonics theory is based on the continental drift theory in that it explains how the supercontinent drifted apart into several plates. The concept of interplay between mantle convection and tectonics goes back to about a century ago, with the proposal. Plate tectonics, and continental drift proprofs quiz. Plate tectonics continental drift and mountain building pdf.
Alfred wegner was a german meteorologist who put forth the continental drift theory in 1912 it is considered that there was a single landmass called pangaea which means all earth. Early evidence for plate tectonics magma generation, igneous intrusions, metamorphism, volcanic action, earthquakes, faulting, and folding are usually the result of plate tectonic activity. Most earthquakes and volcanoes occur along plate boundaries 3. German meteorologist alfred wegener is often credited as the first to develop a theory of plate tectonics, in the form of continental drift. Continents cover 29 percent of the surface of the earth and remainder is under oceanic waters. This was the time when reptiles and winged insects first appeared. Nov 19, 2014 plate tectonics and the continental drift theory by. New ocean crust is created along midocean ridges 4. Theory of continental drift proposed by alfred wegener in 1912, but not widely accepted until. Students explore the basics of wegeners theory of continental drift. The stress required for crustal shortening to build. The continental drift hypothesiscontinents have moved slowly to notetaking worksheet. Plate tectonics and the continental drift theory by. Cartoon illustrating trench retreat and continental drift fig.
Small pieces of crust terranes are important in building up. Plate tectonics should be required reading for all people because we live on a very dynamic planet. A combination of the seafloor spreading theory and the continental drift theory. The first comprehensive theory of continental drift was suggested by the german meteorologist alfred wegener in 1912. Plate tectonics continental drift from circa 1911 alfred wegener, after being influenced by a scientific paper he had come across that listed fossils of identical plants and animals found on opposite sides of the atlantic, began proposing a then most controversial theory which held that the continents of the earth had once been joined together but had drifted apart through a process that he. Oct 31, 2008 continental drift and plate tectonics slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Some researchers propose that a mantle plume generally plays an active role in triggering continental breakup and subsequently driving plate drift e. Jun 20, 20 continental drift and plate tectonics are two theories explaining the geological evolution of the earth, specifically its crust. Continental drift, sea floor spreading and plate tectonics plate tectonics is a theory developed in the late 1960s, to explain how the outer layers of the earth move and deform.
How are plate tectonics and continental drift similar. Plate tectonics theory the upper most mantle, along with overlying crust, behaves as a strong, rigid layer. Continental drift plate tectonics underlined words and phrases are to be filled in by students on the notetaking worksheet. Plate tectonics and continental drift infographic live. In 1915, the german geologist and meteorologist alfred wegener 18801930 first proposed the theory of continental drift, which states that parts of the earths crust slowly drift atop a liquid core. Theory of continental drift proposed by alfred wegener in 1912, but not widely accepted until seafloor spreading was discovered in 1960.
The lithosphere is broken up into seven very large continental and oceansized plates, six or seven mediumsized regional. Continental drift and plate tectonics slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Continental drift theory alfred wegener proposed that parts of earths crust slowly drift atop a. Difference between continental drift and plate tectonics.
It is interesting to note that when the plate tectonics theory gained wide acceptance in the late 1960s, what may actually drive seafloor spreading and continental drift remained unknown. Continental drift, sea floor spreading and plate tectonics. The continental drift hypothesiscontinents have moved slowly to their current locations 1. The fossil record supports and gives credence to the theories of continental drift and plate tectonics. I make a distinction between plate tectonics and continental drift because i think continental drift specifically refers to wegeners hypothesis which didnt have a mechanism and therefore you cant really call it a valid theory because it wasnt accepted by other scientists and it did have some things wrong with it. The idea of continental drift had been ar n since t e 1900s, but lacked enough scientific evi dence to support the theory new advancements after world war il help provide the evidences needed to validate the theory of plate tectonics earthquake evidence scientists noticed that earth uakes do not occur at random locations, but throughout the. The pictures show continental drift theory from 225 million years to present. Then new evidence about earths structure led scientists to reconsider wegeners. Watch this video about continental drift and the mechanism of seafloor spreading create plate tectonics. We then proceed with the presentation of studies of continental drift, seafloor spreading and plate tectonics in convection models allowing for feedbacks. Continental drift and plate tectonics university of iceland.
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