He named this landmass pangaea pan all, gaea earth and the ocean panthalassa pan all, thalassa ocean. Ncert notes continental drift geography notes for upsc. The term was first coined by jt wilson in 1965 and other important thinkers like morgan, mckenzie, parker and holmes independently contributed to this concept. Gradually it broke up into smaller fragments which drifted away to form the present continents. Continental drift theory geography lecture 22 video edurev. In this article we will discuss about the continental drift theory of taylor. Continental drift theory alfred wegener, 1922 plate tectonics breakup of pangea. Continental drift as alternative to contraction theory in the early 20th century, contraction theory was challenged by three independent lines of evidence. Before the carboniferous period, there was a supercontinent pangea surrounded by a superoceanpanthalassa. Geography optional mains upsc ias and pcs digitally learn. According to wegener sial was considered to be limited to the continental masses alone whereas the ocean the crust was represented by the upper part of sima.
This concept was an important precursor to the development of the theory of plate tectonics, which incorporates it. It was an explanation for the issue of drift force, based on which contemporary scientists discarded the continental drift theory. Continental drift theory of taylor theories geography. There he argued for the separation of wegeners pangea into the two super continents, laurasia and gondwana. Continental drift theory basic premise of the theory. Pangaea first split into 2 big continental masses known as gondwanaland and laurasia forming the southern and northern modules respectively. Upsc geography continental drift theory neostencil. He is in fact known as the father of continental drift. Sep 14, 2020 4 pieces of evidence for continental drift by alfred wegener an analysis of evidence and rejection of the theory during the second and third decades of the twentieth century, the notion of continental drift was revived, most notably by the german meteorologist and geophysicist alfred wegener. Ajit tiwari and more top educators are teaching live on unacademy plus.
Alfred wegener suggested continental drift theory in the 1920s. In a lecture in 1912, wegener proposed a startling theory of continental drift. The megaocean is called panthalassa which means all water. He published his observations in a geological comparison of south america with south africa1927, and later he developed his ideas in our wandering continents1937. Nineteenthcentury geologists had worked in great detail to determine the structure of mountain belts, particularly the swiss alps and the north. Later, gondwanaland and laurasia continued to break into several smaller continents that exist today. Alfred wegner was a german meteorologist who put forth the continental drift theory in 1912. Geomorphology for general studies upsc civil services exam. The continents are embedded within the lithospheric plates that comprises the upper 80100 km of the. The concept was independently and more fully developed by alfred wegener in 1912, but his hypothesis was rejected by.
Continental drift theory had been proposed by alfred wegner in 1912, it talked about distribution of continents and the oceans. Apr 02, 2016 the lithosphere is always in a state of work in progress. Although answer is not unsolvable because topic is given entirely in class11 ncert. It was alfred wegener a german meteorologist who put forth a comprehensive argument in the form of the continental drift theory in 1912. Continental drift theory is considered a pivotal theory which provided various conclusive proof to establish the movement of the earth crust but the theory failed to establish the mechanism behind the process. This theory is based on the 2 principle hypothesis arthur holmes convection current hypothesis, and the concept of seafloor spreading advocated by hess.
Arthur holmes in 1930s discussed the possibility of convection. Alfred wegeners continental drift theory and the evidence supporting the theory. In a few cases, the drifting fragments subsequently collided. Alfred wegener 1912 proposed a large super continent pangeasplit into smaller fragments about 200300 million years ago. Upsc course lecture 17 physical geography geomorphology continental drift theory part 4 lecture 7.
A wellwritten answer not only reflects the knowledge of an aspirant but also hisher ability to tailor the content in a manner suited to meet the expectations of the question. According to wegner all continents used to form a single land mass known as pangaea and there was a mega ocean called as panthalassa. Wegener said that continents move around on earths surface and that they were once joined together as a single supercontinent. Theory, examples and pieces of evidence heliumneon laser working and construction ruby laser construction and working continental drift theory by alfred wegener and best supporting evidences types of forest in tamilnadu types of soil found in tamilnadu and its district wise distribution tamil nadu climate conditions. Continental drift theory was given by alfred wegener in 1912 to explain the present arrangement of continents. Continental drift theory geography lecture 22 notes. Dec 16, 2019 continental drift theory alfred wegener, 1922 plate tectonics breakup of pangea. Although now accepted, the theory of continental drift was rejected for many years, with evidence in its favor considered insufficient. The main purpose of his hypothesis was to explain the problems of the origin of. Climatology is the study of the climate weath er conditions averaged over a long period. Feb 25, 2015 theory of continental drift according to wegener, about 300 million years all the continents had formed a single mass, called pangaea which meant all earth. The most accepted theory that explains the following phenomenon.
Initially, the pangaea broke up into two parts of large continents one is called laurasia and another one gondwanaland. These then drifted apart to form the present arrangement of continents. In this article, you will read continental drift theory for the upsc ias exam. Jan 07, 2016 plate tectonics is a scientific theory that describes the large scale motion of the earths lithosphere. This theoretical model is built on the concept of continental drift theory and the sea floor spreading theory. Body discuss the limitations of the theory why there was reluctance in accepting the theory not enough satisfactory explanation to the forces or mechanism that caused these continents to move such great distances. Sep 17, 2020 continental drift theory alfred wegener he postulated that all the earths land had once been joined into a single supercontinent surrounded by an ocean.
The tidal force is not so strong to drift such large landmasses. It is an improvement over the wegeners continental drift theory and has been considered as the most. Apr 06, 2021 continental drift theory geography lecture 22 video edurev is made by best teachers of upsc. Continental drift is now explained as a consequence of moving plates. This was the time when reptiles and winged insects first appeared. Continental drift theory alfred wegener the climatic zones might have shifted from one region to another while the continents stayed at their. What do you understand by the continental drift theory. Use special code ajitlive to get 10% discount on your unacademy plus subscription. Theory of continental drift the continental drift hypothesis was developed in the early part of the 20th century, mostly by alfred wegener.
Meteorology focuses on weather processes and shortterm forecasting in contrast with. Sep 29, 2020 who proposed the theory of continental drift. In this session, akshay sharma will discuss about the continental drift theory and this session will be beneficial for the upsc aspirants. As per continental drift theory, around 200 million years ago, the continent which was joined together called the supercontinent called as pangaea began to move from each other or began to split. Later, a sea called tethys divided pangea into two parts, namely laurentia laurasia or angaraland to the north and gondwanaland to the south of tethys. Alfred wegeners theory of continental drift and evidence. According to continental drift theory there existed one big landmass which he.
Continental drift theory physical geography crack upsc. Wegener and his theory of continental drift indian academy of. The session will be conducted in english and the notes will be provided in english as well. Continental drift and plate tectonics university of iceland. Apr 17, 2018 body after mentioning that theory of plate tectonics is an improvement over theory of continental drift, divide the body into parts and present evidences facts in favour of your stand. Continental drift theory was proposed by alfred wegener in 1912. Apr 09, 2021 plate tectonic theory is based on two major scientific concepts e. Continental drift theory deals with the distribution of the oceans and the continents. A german meteorologist, alfred wegener proposed the continental drift theory in 1912. Continental drift theory proposed by alfred wegener tries to explain the distribution of oceans and continents.
Provide some evidences to support it and its limitation wegener took inspiration from a map of continents to explain the earths geologic history. A large super continent pangea split into smaller fragments about 200300 million years ago. Plate tectonic theory for ugc net, upsc geomorphology. This video is highly rated by upsc students and has been viewed 882 times. According to continental drift theory there existed one big landmass which he called pangaea which was covered by one big ocean called panthalassa. It is one of the earliest theory which talks about rifting and drifting of the continents. This convectional current was the cause of the movement of the earth crust. The speculation that continents might have drifted was first put forward by abraham ortelius in 1596. B, taylor postulated his concept of horizontal displacement of the continents in the year of 1908 but it could be published only in the year 1910. The answer to this question is alfred wegner in 1912.
One problem was that a plausible driving force was missing. Bring about the basic differences between the drift theory. Continental drift theory continental drift is the hypothesis that all the continents had once been joined together in a single landmass. Based on the fossils record, he found that many fossils originated in a temperate or cold climate are found in the tropical regions. In 1967, mckenzie and parker suggested the theory of plate tectonics. Continental drift theory this theory was the first comprehensive theory to talk about the drifting of continents. Opponents of continental drift theory pointed out that the centrifugal and tidal force were not large strong enough to move continents. According to the theory of plate tectonics, the earths lithosphere is broken into distinct plates which are floating on a ductile layer called asthenosphere upper part of the mantle. It is considered that there was a single landmass called pangaea which means all earth. Continental drift theory has been asked in previous geography optional papers of 1980, 1996, 2000, 2007.
Continental drift theory geography lecture 22 notes edurev is made by best teachers of upsc. Mar 30, 2020 according to this theory, the supercontinent, pangaea, began to split some two hundred million years back. Trained as a meteorologist, he was intrigued by the exact fit of africas and south. This document is highly rated by upsc students and has been viewed 651 times.
Continental drift was not accepted when first proposed, but in the 1960s it became a cornerstone of the theory of global plate tectonics. Continental drift is the hypothesis that the earths abraham ortelius in 1889, in his manual of geology 1863, dana wrote, the continents and oceans had their. Discuss the evidences in support of it and also throw light on the criticism faced by it. Theories continental drift theory, sea floor spreading. Pangaea all earth, panthalassaall water,laurasia northern and gondwana southern and tethys between them, evidences in support of continental drift theory,limitation of continental drift theory. Continental drift theory ncert wegener proposed that the movement accountable for the drifting of the continents was instigated by tidal force and polefleeing. Continental drift theory evidences and limitations question throw some light on theory of continental drift. According to alfred wegener, all the continents formed a single continental mass and mega ocean surrounded the same. The lithosphere, which is the rigid outermost shell of our planet the crust and the upper mantle is broken up into tectonic.
In 1912, a german geologist named alfred wegener came up with an outlandish theory known as continental drift. Continental drift theory geography lecture 22 video. Forces responsible for the drift are a tidal force resulting in the westward movement of the continents. Continental drift theory day 22 upsc prelims revision in. He had no satisfactory mechanism to offer, but appealed to a lessdense continent floating and drifting over a more dense. Continental drift theory by alfred wegener geography upsc cse. Right click on the image and open image in new tab removedelete the resolution part from the url. Mains answer writing sample answers for upsc mains. Alfred wegener believed in three layers system of the earth e.
The generation of this current due to radioactive elements causing thermal differences in the mantle portion. Continental drift theory day 22 upsc prelims revision. Any book on physical geography will contain the topic on continental drift. Continental drift theory to explain the present distribution of oceans and continents, various theories have been proposed.
Sep 08, 2020 the development towards the theory began in the 1960s with extensive seafloor mapping. Continental drift theory in 1912 alfred wegener 18801930 postulated that all the continents once were together forming a single continent. Gk, general studies, optional notes for upsc, ias, banking, civil services. Continents cover 29 percent of the surface of the earth and remainder is under oceanic waters. Upsc mains answer writing practice answer writing is a continuous exercise that is an inalienable part of the preparation process for the civil services examination. According to wegener sial was considered to be limited to the continental masses alone whereas the ocean the crust was. Continental drift theory ncert wegener proposed that the movement accountable for the drifting of the continents was instigated by tidal force and pole fleeing. Compare and contrast, the continental drift theory, sea.
Although the theory has some lacunae but it is the foundation for modern theories such as plate tectonics and sea floor spreading. The first continental portion of the earth was called pangea, and the oceanic part was called panthalassa. According to him, about 250 million years ago, the earth was made up of a single landmass called pangaea meaning all lands, and a single ocean surrounding it called as panthalassa. Pangaea was named for the supercontinent that means all the whole earth. Continental drift is the hypothesis that the earths continents have moved over geologic time relative to each other, thus appearing to have drifted across the ocean bed. Cause and locations of volcanic eruption, earthquakes, tsunamis, the process of mountain building. Continental drift theory evidences and limitations.
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