Ret 2006, rev 2 7 introduction to plate tectonic theory, geodesy, and vlbi the plate tectonic theory is a relatively new, accepted only around 50 years ago. 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. Each province is a piece of californias tectonic jigsaw puzzle. The following website contains a more detailed and lesson plans on plate tectonics, geodesy, and vlbi.
This module describes how the work of alfred wegener, harry hess, and others led to our understanding of plate tectonics. It has been developed to explain large scale motions of the earth s lithosphere. They float on top of the semiliquid asthenosphere convection currents in the asthenosphere slowly move the plates. Each type of interaction causes a characteristic set of earth structures or tectonic features. Plate tectonics theory is taught in science classrooms around the world, but just 50 years ago it was a hotly contested theory. Plate tectonics and orogeny the concept of plate tectonics, or new global tectonics. Jan 23, 2020 plate tectonics is the scientific theory that attempts to explain the movements of the earths lithosphere that have formed the landscape features we see across the globe today. New crustal plate is formed at the midocean ridges and old crustal plate. Since the theory of plate tectonics was first introduced, how far has the tectonic plate were standing on moved. Plates are composed of the crust and a part of the upper mantle, these two parts together are called the lithosphere. 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. You will recall from a previous chapter that there are three. 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.
Tectonic plates are pieces of the lithosphere, which is a layer of brittle rock that corresponds to the crust and the upper lab 2. Iceland is one of the few places where this process can be seen on land. What evidence exists to support the theory of plate tectonics. The plates float on the earths mantle and are constantly moving at a very slow rate. The theory of plate tectonics activityworksheet 3 volcanoes 8. Principally it refers to the movement and interaction of the earths lithosphere. He also proposed a tectonic cycle the wilson cycle to describe the lifespan of an ocean basin. New oceanic crust is formed through magma rising through the gap and cooling. Mar 21, 2020 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. The three types of boundries are,spreading, colliding, and sliding boundries. Plate tectonics thus provides the big picture of geology. The theory of plate tectonics key concepts what is the theory of plate tectonics. Locations of earthquakes and volcanoes show the plate boundaries and ocean floor features.
I think it is interesting to consider how long the plate tectonics revolution took to unfold. The theory of plate tectonics understanding main ideas label each. The theory of plate tectonics describes how the plates move, interact, and change the physical landscape. The geoscientific community accepted plate tectonic theory after seafloor spreading was validated in the early 1960s. Each major piece of cracked crust is called a tectonic plate figure 22. Looking at the information you compiled in your chart above, explain one way the theory of plate tectonics can relate to engineering. Continental drift, in the context of the modern theory of plate tectonics, is explained by the movement of lithospheric plates over the asthenosphere the molten, ductile, upper portion of the earths mantle. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
The outlines of the continents flanking the atlantic ocean are so similar that their correspondence was apparent as soon as accurate maps became available. Plate tectonics overview the earths crust is cracked like the shell of a hardboiled egg. According to the theory of plate tectonics, the earths lithosphere is broken into distinct plates which are. Earths geography has changed through time and continues to change today. Consider that wegener published origin of the continents and oceans in 1915 in which he laid out the circumstantial evidence that indicated the continents had once been joined, but plate tectonics was not accepted as a theory until about 1968. We now know that, directly or indirectly, plate tectonics influences nearly. In 1967, mckenzie and parker suggested the theory of plate tectonics. Strain builds up along plate boundaries, and when the strain becomes too great, fractures form and.
Continental drift and the development of plate tectonic theory. Plate tectonics is the theory that explains how large pieces of the earths outermost layer, called tectonic plates, move and change shape. It provides us with a way to tie together what once was considered unrelated geologic. The rigid lithosphere is split into 15 major plates that slowly move on. The theory of plate tectonics grew out of earlier hypotheses and observations collected during exploration of the rocks of the ocean floor. The crust is made up of six major plates and a number of minor ones. Plate tectonic theory both hesss discovery and wegners continental drift theory combined into what scientists now call the plate tectonic theory.
In addition, the diving plate melts and is often spewed out in. By definition, the word plate in geologic terms means a large slab of solid rock. The present chapter provides an introduction to plate tectonic theory and describes the main deformation patterns of the earths crustal material influencing the surface morphology and landforms. Chapter 1 plate tectonics power point linkedin slideshare. In this plate tectonic framework, large scale deformation is the local response of the lithosphere to induced stresses. Alfred wegener created the idea of continental drift and wrote the origin of continents and oceans to support his idea. Geosynclinal theory the emergence and evolution of plate. Continental drift, sea floor spreading and plate tectonics. Plate tectonics is the theory that earth s outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core. Introduction to plate tectonic theory, geodesy, and vlbi. The structure of the earth, plate tectonics and landforms. Seafloor spreading occurs at divergent plate boundaries which subsequently create midocean ridges. The following overview of plate tectonics provides a view of the big picture of californias geologic heritage. The continents are carried on some of these plates.
What is plate tectonics the earths crust and upper mantle are broken into sections called plates. In the early 1960s, the emergence of the theoryof plate tectonicsstarted a revolution in the earth sciences. Earths lithosphere is broken into separate sections called plates. Convection current theory cct convection current theory forms the basis of sfst and pt. Since the development of the theory, geologists have had to reexamine almost every aspect of. 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. History of plate tectonics plate tectonic theory had its beginnings in 1915 when alfred wegener proposed his theory of continental drift. Plate tectonics is a theory that explains the features and movement of earths surfaces currently and in. The theory of states that earths surface is divided into large plates of rock. Wegeners theory and sea floor maps were used to develop the theory of plate tectonics.
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. Plate tectonics is the geological theory that states that pieces of earths lithosphere are in constant, slow motion, driven by convection currents in the mantle. Origins of plate tectonic theory earth science visionlearning. These smaller, broken plates form a more fluid rock surface in the mantle. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. Seafloor spreading helps explain continental drift in the theory of plate tectonics. His ideas have been scientifically proven as time goes on. The earth is composed of layers of different composition and physical properties, principally the solid central core, the fluid peripheral core, the viscous mantle, and the solid. Plate tectonics is the framework in which geologists study and understand the inner workings of the earth. There was an increasingly wide acceptance of the theory of plate tectonics.
The earliest references to this similarity were made in 1596 by flemish cartographer abraham ortelius and later in 1620 by the english philosopher francis bacon, in his. Plate tectonicsthe unifying theory of geology geology. The theory of plate tectonics geology lumen learning. At plate boundaries, plates collide, move apart, move under or over each other, or slide past one another. 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. The theory of plate tectonics explains the formation, movement, and subduction of earths. Plate tectonics theory predicts the locations of earthquakes, volcanoes, mountain ranges, ore deposits, and other geological phenomena. Plate tectonics is the unifying theory of the earth how did the theory develop. These boundaries are places where two plates are pushing toward, pulling away, or sliding past each other.
Frank taylor first proposed this idea in 1910, alexander du toit later in 1937, harry hess explored the geomorphology of the seafloor by ship in 1960s. The theory has caused a revolution in the way we think about the earth. The theory of plate tectonics explains how plates and their continents move. The movements rate has been determined to be approximately 5 10 cm per year 2 6 inches per year, depending on location of the plates. Geological features of divergent plate boundaries our mission is to provide a free, worldclass education to anyone, anywhere.
The fundamental concepts for geosynclinal theory were introduced in james halls presidential address for the geological society of america at the meeting of the american association for the advancement of science at montreal in 1857 knopf, 649. As plates move, the new crust gradually moves away from the ridge. It explains plate tectonics as the driving force behind ongoing changes on earth. Think pair share how might the movement of tectonic plates affect climate. What is tectonic plates and plate tectonics tectonic plates giant jigsawlike pieces of the earths crust. Plate tectonics and the rock cycle the theory of plate tectonics states that the crust of the earth is composed of 7 major plates and numerous smaller plates. Plate tectonics development of tectonic theory britannica. Plate tectonics is the theory that explains the global distribution of geological phenomena. Along spreading centers in the sea floor, melted rock rises through cracks, cools, and. The theory of plate tectonics and continental drift bartleby. What are the three types of tectonic plate boundaries. Plate tectonics the earths crust is divided into plates which are moved in various directions. The theory of plate tectonics helps explain this pattern because the earthquake and volcano belts mark the locations of plate boundaries. The earth surface has continuously been changing ever since it was formed, especially regarding the geomorphological and geological phenomena.
Notes on plate tectonics plate tectonics states that the earths crust and upper mantle are broken into sections, called plates. These plates are like a hard shell over the mantle, and the most outer layer is called the lithosphere. Nov 16, 2010 plate tectonic theory states that the earths outer layer is fragmented into plates that are in constant motion. As scientists learned more about seafloor spreading and magnetic reversals, they formed a theory to explain how continents move. The theory of continental drift was the first step toward plate tectonic theory, which became the foundation upon which modern geology is built.
Plate tectonics, our major paradigm for how the earth works, was established in the 1960ies following decades of observational research that culminated in key discoveries such as geomagnetic. The plate tectonics gizmo shows a crosssection, or side view, of earth. List and describe the evidence for the plate tectonics theory. 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.
Plate tectonics plate tectonics is the unifying theory of geology and revolutionized geology cornerstone of earthsystem approach. This video tutorial helps explain the basics of plate tectonic theory. The earths plates jostle about in fits and starts that are punctuated with earthquakes and volcanic eruptions. Each plate moves over earths and changes position with respect to other plates. Continental drift theory alfred wegener, 1922 plate tectonics breakup of pangea. Over time, the plates move and morph into natural land boundaries. The new model of horizontal movement of the continents was called plate tectonics. 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. When one plate dives under another plate, earthquakes can result and can form. These plates move relative to one another above a hotter, deeper, more mobile zone at average rates as great as a few inches per year. The theory of plate tectonics neshaminy school district.
Jan 28, 2017 theory of plate tectonics was established by alfred wegener. After harry hess described the idea of seafloor spreading, scientists found more evidence that continents can move. This plate motion causes them to collide, pull apart, or scrape against each other. The major mountainbuilding idea that was supported from the 19 th century and into the 20 th is the geosynclinal theory. When the concept of seafloor spreading came along, scientists recognized that it was the mechanism to explain how continents could move around earths surface. Development of plate tectonic theory timeline preceden. Plate tectonics is the theory used to explain the structure of the earths crust and many of the associated phenomenon. The lithosphere lithosphere is comprised of the upper mantle and the crust, the outer shell of the earth.
The earths crust and part of the upper mantle are broken into sections, called plates which move on a plasticlike layer of the mantle. Plate tectonics information and facts national geographic. The layer below the lithosphere is the asthenosphere. Plate tectonics describes the distribution and motion of the plates. Theory of plate tectonics advances in technology in the 1960s led to the development of the theory of plate tectonics which validated but improved upon wegeners earlier 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. Plate tectonics plate tectonics development of tectonic theory. Chapter 3 plate tectonics topic the theory of plate.
According to the generally accepted plate tectonics theory, scientists believe that earths surface is broken into a number of shifting slabs or plates, which average about 50 miles in thickness. Plate tectonics pt plate tectonics is the movement of lithospheric plates relative to each other. The lithosphere is broken up into 9 major and many smaller plates. Plate tectonics according to the theory of plate tectonics. This theory builds on older ideas of continental drift and seafloor spreading. Plate tectonics is a scientific theory describing the largescale motion of seven large plates and the movements of a larger number of smaller plates of the earths lithosphere. This is a revised version cleaning up the graphics and the scriptnarration. This includes the formation, movement, collision and destruction of plates and the resulting geological events such as seismicity, volcanism, continental drift, and. Lets back up and first define plate tectonics by tectonics, we mean, the processes, stresses forces and motions of the earths crust and underlying mantle layer. Plate tectonics the theory of plate tectonics this section explains how the lithosphere is broken into separate sections that move. I deleted the original version, which had 17,110 views, 4 comments, 81 thumbs ups. The theory of plate tectonics states that the earths surface, the upper mantle and crust, was once made up of enormous rock plates that broke into smaller pieces approximately 300 million years ago. The theory of plate tectonics states that earths lithosphere is broken.
617 383 1321 62 642 1415 1277 310 473 822 280 418 178 1083 48 1465 1314 599 326 1479 1216 133 894 338 1028 1625 833 532 1232 238 649 24 65 1376 1052 62 645 1467 852 67 579 1182 1291 1026 1164 196