This was the time when reptiles and winged insects first appeared. Paleomagnetism and continental drift this old earth. Continental drift was a theory that explained how continents shift position on earths surface. Continental drift theory continental drift is the hypothesis that all the continents had once been joined together in a single landmass. In this lesson, students learn about the evidence for continental drift and about the process of science. Willi hennig 1950 introduced the modern concepts of phylogenetic theory. Magnetic polarity evidence for continental drift discusses how the lack of a plausible mechanism kept wegeners colleagues from accepting his continental drift hypothesis. Continental drift refers to the movement of the continents relative to each other. This indicates that these continents had to be once joined together because the extensive oceans between these land masses act as a type of barrier for fossil. Hundreds of millions of years ago, earth looked completely different. In other words, the paleomagnetic evidence appears to.
Wegener and his theory of continental drift indian academy of. Wegener said that continents move around on earths surface and that they were once joined together as a single supercontinent. We now know that, directly or indirectly, plate tectonics influences nearly all geologic processes, past and present. Mesosaurus small fresh water reptile glossopteris plant remains. The continental drift hypothesis was developed in the early part of the 20th century, mostly by alfred wegener. Therefore, rationalist approaches suggest that evidence can be enough by itself to close scientific controversies. Fossils we gener learned that the fossils of an ancient reptile, mesosaurus mehzuhsawruhs, had been discovered in south america and western africa. The concept was independently and more fully developed by alfred wegener in 1912, but his theory was rejected by many for. The speculation that continents might have drifted was first put forward by abraham ortelius in 1596. The students will be able to identify the evidence for continental drift and locate them on a map. Fossils wegener learned that the fossils of an ancient reptile, mesosaurus mehzuhsawruhs, had been discovered in south america and western africa. Evidence of the continental drift essay example graduateway.
Cut out each of the continents along the edge of the continental shelf the outermost dark line. On the puzzle pieces handout, assign a color to each type of fossil or mountain belt in the legend and color the areas on the landmasses according to the legend. You will be piecing together a puzzle of the supercontinent pangaea based on fossil and rock evidence on the presentday continents. We are taught that modern scientists are driven only by reason and facts. In the early 1960s, the emergence of the theory of. To learn about the continental drift theory and the evidence that supports it. Introduction in 1915 wegener published a book the origin of continents and. Continental drift, paleomagnetism, and plate tectonics history continental drift continental drift alfred wegener 1915 he was the first strong proponent of continental drift he published the origin of continents and oceans he proposed that a supercontinent named pangaea pan all, gaea earth split into the present continents.
Vocabulary word to know resource exploitation resource use sustainability land use native species introduced species. In some places, it slides under the continental crust and. Through the theory of continental drift, humans have been able to figure out how the earths crust moves and the causes of volcanoes, earthquakes, oceanic trenches, formation of mountain ranges and other geological occurrences. Some of the evidence supporting the continental drift of the tectonic plates include the presence of similar animals and plant fossils on the shores of various continents, which suggest that they were once joined. Continental drift updated 2018 a brief overview of the theory of continental drift and the evidence supporting it.
He then gathered an impressive amount of evidence to show that earths continents were once connected in a single supercontinent. In this article i analyse continental drift debates. What are six things that supported wegeners theory of continental drift. A teaching companion us geological survey, may 1999. Alfred wegeners theory of continental drift and evidence. Chapter 1 from continental drift to plate tectonics naomi oreskes since the l6th century, cartographers have noticed the jigsawpuzzle fit of the continental edges. Evidence for continental drift adapted from this dynamic planet. This evidence for continental drift gave geologists. Many in the scientific community of the day criticized it, yet today it is the accepted view by mainstream science. The evidence which gave rise to the theory of continental drift more correctly called plate tectonics includes the following. He propounded his concept on continental drift in the year 1912. Continental drift wikipedia, the free encyclopedia. The theory of continental drift was first proposed by alfred wegener in 1912. Pdf styles of thought on the continental drift debate.
You can enjoy this soft file pdf in any become old you expect. Another important piece of evidence in the continental drift theory is the fossil relevance. Plate tectonics theres a continent called pangaea well, there once was. Use those same colors to color each type of fossil or mountain belt according to your legend. The reaction to alfred wegeners theory tells us much about the workings of science. Try to work out which of these pieces of evidence wegener might have used in the 1920s to support his. The coasts of the continents surrounding the atlantic ocean could, if the continents were moved closer, fit together like a jigsaw puzzle.
Continental drift theory evidences and limitations. We have learned that rock samples containing magnetic. Continental drift is defined as the motion of the earths continents over a defined period of time. Subduction zone oceanic crust is heavier than continental crust. Thus, proposed in 1912 by alfred wegener, continental drift theory explained why similar looking animal and plant fossils and. Theory of continental drift physical geography lumen learning. Fossils certain fossils preserved in rocks of the same age but from different continents. Color the legend on the puzzle pieces handout according to the key. From this he began plotting worldwide distributions of both rock and. Continental drift, largescale horizontal movement of continents relative to one another and to the ocean basins during one or more episodes of geologic time.
More evidence that supported wegeners theory of continental drift climate clues o he found evidence of glaciers in tropical areas. Paleomagnetism and the proof of continental drift more than 1,500 years ago, chinese sailors discovered that a piece of lodestone, when suspended from a thread, points in a northerly direction and can help guide a voyage. Besides the way the continents fit together, wegener and his supporters collected a great deal of evidence for the continental drift. Ncert notes on important topics for the upsc civil services exam. In the early 1960s, the emergence of the theoryof plate tectonicsstarted a revolution in the earth sciences. Alfred wegener, pangea, and the evidence for continental. Tectonics, continental drift theory by alfred wegener, evidence and drawbacks of continental. Bookmark file pdf plates tectonics and continental drift answer key plates tectonics and continental drift answer key continental drift and plate tectonics continental drift and plate tectonics. As a meteorologist alfred wegener was well aware of some climatological puzzles, such as the remains of temperate climate trees that can be found under polar ice. Polar wandering similar to continental drift theory polar wandering is the relative movement of the earths crust and upper mantle with respect to the rotational poles of the earth. In 1915 wegener published a book the origin of continents and.
Seafloor spreading theory sfst seafloor spreading describes the movement of. Pdf a historical account of how continental drift and plate tectonics. My friends and i are here to present my theory of continental drift, which i published in the year 1915. By the mid twentieth century enough evidence had been amassed to begin openning the minds of many scientists to the idea that the continents could have moved across the surface of the earth. He had initially become fascinated by the nearperfect fit between the coastlines of africa and south america, and by the commonality among their geological features, fossils, and evidence of a glaciation having affected these two separate continents. Evidence for continental drift wegener gathered evidence for his hypothesis from fossils, from studies of ancient climate, and from the geology of continents. Continental drift, paleomagnetism, and plate tectonics. Magnetic polarity evidence for continental drift read.
As stated before the theory of continental drift has strong points of evidence one being the physical feature, how all of the continents, for the most part, fit together like puzzle pieces for example, africa and south america. Alfred wegeners fossil evidence for continental drift is shown on the cutouts. 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. On the puzzle pieces handout, assign a color to each type of fossil or mountain belt in. In 1912, alfred wegener proposed a theory that the continents had once been joined, and over time had drifted apart. We now know that, directly or indirectly, plate tectonics influences nearly all. Evidence for continental drift we gener gathered evidence for his hypothesis from fossils, from studies of ancient climate, and from the geology of continents. It is thought that all the continents were once joined together in one supercontinent, named pangaea.
Fossils of a freshwater reptile known as mesosaurus was found both in south africa and brazil. While wegener was alive, scientists did not believe that the continents could move. There are multiple lines of evidence for changes in the position of the continents over geologic. Continental drift theory states that the continents have not always been in their present locations but. There are various examples of fossils found on separate continents and in no other regions. Continental drift this video describes the evidence alfred wegener used to. The evidence for tectonic plate motion was radical in the early and midtwentieth century. Wegener and his theory of continental drift springerlink. Several types of evidence in rocks on land and on the seafloor and in the animal and plant kingdoms may be explained simply if we assume that the continents. You will be piecing together a puzzle of the supercontinent pangea based on fossil and rock evidence on the present day continents. This article talks about the continental drift theory upsc.
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