We now know that, directly or indirectly, plate tectonics influences nearly. Plate tectonics is a theory developed in the late 1960s, to explain how the outer. Pdf geological evidence for the operation of plate tectonics. Continental drift theory alfred wegener, 1922 plate tectonics breakup of pangea. The earth surface has continuously been changing ever since it was formed, especially regarding the geomorphological and geological phenomena. Plate tectonics thus provides the big picture of geology. This video was produced by rasa juras, an undergraduate at the university of st andrews for the. Principally it refers to the movement and interaction of the earths lithosphere. Exploring evidence of plate tectonics using geomapapp. Students will research the evidence collected to support the theory of plate tectonics as we know it.
Alfred wegener suggested continental drift theory in the 1920s. Evidence of plate tectonics exploring earthquakes it seems javascript is either disabled or not supported by your browser. 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. Together, these plates constitute the lithosphere, from the greek lithos, meaning rock. Plate tectonics is the theory that explains how large pieces of the earths outermost layer, called tectonic plates, move and change shape. What is the strongest piece of evidence in support of the plate tectonic theory. List and describe the evidence for the plate tectonics theory. The world map above shows the plate boundaries as well as active volcanoes.
Evidence from fossils, glaciers, and complementary coastlines helps reveal how the plates once fit together. Continental drift, sea floor spreading and plate tectonics. Demonstrating the movement of the earths crust and how tectonic plates interact at plate boundaries the theory of plate tectonics. Plate tectonicsthe unifying theory of geology geology. Demonstrating the movement of the earths crust and how tectonic plates interact at plate boundaries the theory of plate tectonics the crust is the outer layer of the earth.
The drawing above is a cross section of the earth showing the components that lie within plate tectonic theory. Explain the process that causes the earths tectonic plates to move. This tectonic cycle has influenced the distribution of. This diagnostic sequence consists of glacial deposits called tillites, followed by sandstones and finally coal measures, typical of warm moist climates. Start studying plate tectonics theory learn vocabulary, terms, and more with flashcards, games, and other study tools. Since the development of the theory, geologists have had to reexamine almost every aspect of. Keith challenges the very foundation of the plate tectonic model. Plate tectonics have students team read pages 158 and 159 to. Plate tectonics describes the distribution and motion of the plates. In 1967, mckenzie and parker suggested the theory of plate tectonics. Who proposed the theory and what evidence did he provide to prove his theory. What evidence supports the theory of plate tectonics. Plate tectonics evidence supporting the hypothesis.
Modern continents hold clues to their distant past. He put together the evidence of ancient glaciations and the. Indeed, the notion that the entire earths surface is continually shifting has profoundly changed the way we view our world. This is because convection cell currents have not been proved conclusively to exist due to technological limitations we have never been able to get deep enough into earth to prove the theory. Earths geography has changed through time and continues to change today. Prior to the year 1900, most scientists that studied geology believed that the present position and shape of the earths continents changed very little over time.
The drawing above is a cross section of the earth showing the. In plate tectonics, students are introduced to the theory behind this geophysical phenomenon and investigate the evidence that supports it. What evidence do we have for plate tectonics is part of the geobus geology in a minute series. Plate tectonicsthe unifying theory of geology geology u.
The evidence that rocks closer to mid ocean ridges are younger than rocks farther away supports the theory of. Plate tectonic theory observing convection currents convection currents are the major driving force behind the movement of tectonic plates. Evidence from fossils, glaciers, and complementary coastlines helps reveal how plates once fit together. Plate tectonics theory is taught in science classrooms around the world, but just 50 years ago it was a hotly contested theory. The project requires that they find 15 distinct bodies of evidence for plate tectonics and find the scientists who are credited for each. Earths surface layer, 50 to 100 km 30 to 60 miles thick, is rigid and is composed of a set of large and small plates. Plate tectonics is the theory that the outer rigid layer of the earth the lithosphere is divided into a couple of dozen plates that move around across the earths surface relative to each other, like slabs of ice on a lake. Plate tectonics is the movement of lithospheric plates relative to each other. The theory of plate tectonics combine which two other theories. That continent eventually separated and drifted apart, forming into the seven continents we have today. Plate tectonics is the grand, unifying theory of earth sciences, combining the concepts of continental drift and seafloor spreading into one holistic theory that explains many of the major structural features of the earths surface.
The evidence for plate tectonics is very conclusive. Students investigate plate tectonic environments convergent, divergent, transform boundaries, topographybathymetry of continents and ocean basins, the distribution and pattern of earthquakes, the distribution of volcanoes, as well as ages of the seafloor, and more. 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. The theory of plate tectonics grew out of earlier hypotheses and observations collected during exploration of the rocks of the ocean floor.
As the plates move, of course, so will the continents. Theory of continental drift proposed by alfred wegener in 1912, but not widely accepted until seafloor spreading was discovered in 1960. It is made up of thick, interconnecting pieces called tectonic plates that fit together like a puzzle. One of the biggest questions in geosciences today is when did plate tectonics begin on earth with a wide range of theories based on an equally diverse set of. Plate tectonics is the unifying theory of the earth how did the theory develop. According to the theory of plate tectonics, the earths lithosphere is broken into distinct plates which are. This might appear to be convincing evidence of plate tectonics theory. The evidence against plate tectonic theory is due to the mechanics of plate movement. According to the theory of continental drift, the world was made up of a single continent through most of geologic time. That continent eventually separated and drifted apart, forming into the seven. Along the way, i disclose details of what real science is all about, details all too often absent in textbooks and classroom discussions.
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. Then have them reread to identify observations that the theory of plate tectonics explains. They move atop the underlying mantle, a really thick layer of hot flowing rock. The motion in the mantle the asthenosphere is caused by convection currents. Convection current theory cct convection current theory forms the basis of sfst and pt. Plate tectonics the tectonic plates of the world were mapped in the second half of the 20th century. A plate tectonic puzzle introduction the earths crust is not a solid shell. Continental drift is the movement of the earths continents relative to each other, thus appearing to drift across the ocean bed. The continental drift theory is the theory that once.
Continental drift and the development of plate tectonic theory. Based on the pace of your course, you may need to adapt the lesson plan to fit your needs. It is a very well supported theory, and while scientific debate continues about small parts or local effects, the overall concept is accepted as good as fact. L1 advanced readers plate motions point out that the arrows in figure 20 show the direction of plate motion. Finally, evidence is to be found at the plate boundaries themselves. 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. You will recall from a previous chapter that there are three major layers crust, mantle, core within the earth that are.
Despite the evidence wegener collected, he could not provide a theory explaining how the continents moved. In part 1, students view flash interactives and quicktime videos which delineate the relationship between volcanoes, earthquakes and plate boundaries and discuss the ancient continent of pangaea. The theory of plate tectonics geology lumen learning. What is the main evidence against the plate tectonics theory. All this evidence, both from the ocean floor and from the continental margins, made it clear around 1965 that continental drift was feasible and the theory of plate tectonics, which was defined in a series of papers between 1965 and 1967, was born, with all its extraordinary explanatory and predictive power. Students will explore tectonic plate boundaries and different types of seismic waves generated by earthquakes. Continental drift refers to the movement of the continents relative to each other. According to continental drift theory there existed one big landmass which he called pangaea which was covered by one big ocean called panthalassa. Dec 16, 2019 it explains the force behind plate movements. The earths structure plate tectonic theory wjec gcse. First, gather a bottle of food coloring and a large, clear glass container.
From wikipedia, the free encyclopedia plate tectonics from greek, tekton builder or mason describes the large. The theory of plate tectonics is based on several assumptions, the most important of which are. The strikingly similar paleozoic sedimentary sequences on all southern continents and also in india are an example of evidence that supports continental drift. Plate tectonics is the theory that explains the global distribution of geological phenomena. This activity requires students to explore a range of datasets that help substantiate plate tectonic theory. It started as a hypothesis and had to be proven with hard evidence before being completely accepted by the scientific community. In the early 1960s, the emergence of the theoryof plate tectonicsstarted a revolution in the earth sciences. Completed timelines can be done in any format ranging fro. Locations of earthquakes and volcanoes show the plate boundaries and ocean floor features. The first comprehensive theory of continental drift was suggested by the german meteorologist alfred wegener in 1912. The theory of plate tectonics, like every scientific theory, resulted from centuries of observations and compilation of many scientists works. The earths crust and part of the upper mantle are broken into sections, called plates which move on a plasticlike layer of the mantle. You will recall from a previous chapter that there are three. The theory of continental drift wegener 1880 1930 alfred wegener first proposed the theory of continental drift.
The idea that the earths crust is made up of huge tectonic plates that are floating on an ocean of molten hot magma seemed too fantastic to be believed. In essence, platetectonic theory is elegantly simple. Prior to the year 1900, most scientists that studied geology believed that the present position and shape of. To help your child visualize the convection process that drives tectonic plate motion, try doing this simple experiment together. Plate tectonics is the unifying theory of geology and revolutionized. Scientists found evidence from molten material, magnetic stripes, and drilling samples to back up wegeners theory. In his seminal paper in 1993, with the thoughtprovoking title geodynamics and mantle flow. We now know that, directly or indirectly, plate tectonics influences nearly all geologic processes, past and present. Plate tectonics plate tectonics evidence supporting the hypothesis. Plate tectonic theory arose out of the hypothesis of continental drift proposed by alfred wegener in 1912 6 and expanded in his 1915 book the origin of continents and oceans. If it is to be understood that the earths crust is broken and divided into plates and that these plates are in constant movement and contact, then evidence would surely be found at the plate boundaries. Below is a sample breakdown of the plate tectonics chapter into a 5day school week. Seafloor spreading theory sfst seafloor spreading describes the movement of.
Following the plate tectonic theory, the continents on the plates are still moving today, albeit very slowly. This includes the formation, movement, collision and destruction of plates and the resulting geological events such as seismicity, volcanism, continental drift, and. Plate tectonic theory both hesss discovery and wegners continental drift theory combined into what scientists now call the plate tectonic theory. This distribution of fossils led to theories that the southern continents were once joined in a supercontinent called gondwana.
Describe the historical development of evidence that supports plate tectonic theory. Describe the type of plate boundary that forms mountains and islands. Plate tectonics, theory dealing with the dynamics of earths outer shell that revolutionized earth sciences by providing a uniform context for. What evidence did scientists find in the himalayas that support the theory of plate tectonics. Oct 24, 2016 what evidence do we have for plate tectonics is part of the geobus geology in a minute series. A middle school lesson on plate tectonics theory for grades 68.
New plate material is generated at ocean ridges, or constructive plate boundaries. 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. The theory has caused a revolution in the way we think about the earth. Read the background information and answer the following questions.
Plate tectonic theory arose out of the hypothesis of continental drift. Plate tectonics it was from the continental drift theory, convection current theory and the theory of seafloor spreading, the theory of plate tectonics was formulated. Dec 17, 2019 plate tectonics it was from the continental drift theory, convection current theory and the theory of seafloor spreading, the theory of plate tectonics was formulated. It may be fantastic, but that is exactly what is happening.
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