The structure of the earth, plate tectonics and landforms. 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. Central to the theory of plate tectonics is the concept of. Against plate tectonics on earth the plate tectonics theory. Plate tectonics summary the earth is made up of 3 main layers core, mantle, crust on the surface of the earth are tectonic plates that slowly move around the globe plates are made of crust and upper mantle lithosphere there are 2 types of plates there are 3 types of plate boundaries volcanoes and earthquakes are closely. When using the powerpoint slides as a learning resource, it is important to read the notes that accompany. Each type of interaction causes a characteristic set of earth structures or tectonic features. Watch the plate tectonics explained youtube clip and have a go at explaining what plate tectonics are in your own words. Below this is a zone that slows earthquake waves because the mantle here is plastic rather than brittle. Tectonic plates are pieces of earths crust and uppermost mantle, together referred to as the lithosphere. The currents would be at parts parallel to giant plates on the surface and carry them. A synopsis of plate tectonics james madison university. Plate tectonics conclusion 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. Sep 17, 2009 the theory of plate tectonics explains how plates and their continents move.
Locations of earthquakes and volcanoes show the plate boundaries and ocean floor features. Powerpoint presentations introducing fundamental concepts and observations of plate tectonics and earthquakes. 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 plates are around 100 km 62 mi thick and consist of two principal types of material. Sep 25, 2012 plate tectonics summary the earth is made up of 3 main layers core, mantle, crust on the surface of the earth are tectonic plates that slowly move around the globe plates are made of crust and upper mantle lithosphere there are 2 types of plates there are 3 types of plate boundaries volcanoes and earthquakes are closely. 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. In part 1 of this activity, students are provided with a blank topographic profile and an associated tectonic plate boundary map.
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 information and facts national geographic. The theory of plate tectonics proposes that the lithosphere is divided into a series of plates that fit together like the pieces of a jigsaw puzzle. Wegener believed that all of the continents were connected as one large land mass he called pangea about 200 million years ago.
This technique, now known as seismic tomography, enables scientists to. This plate motion causes them to collide, pull apart, or scrape against each other. According to the theory of plate tectonics, the earths lithosphere is broken into distinct plates which are. The evolution of plate tectonics article pdf available in philosophical transactions of the royal society a mathematical physical and engineering sciences 37622. A plate can comprise both oceanic and continental lithosphere. Students are asked to draw a schematic crosssection on the profile down to the asthenosphere including tectonic plates with relative thicknesses of crust etc. Mar 01, 2016 this video briefly discusses the theory of tectonic plates, the different types of plate boundaries and their surface features. In the frame of plate tectonics several models have been constructed on its unproved assumption. A plate tectonic puzzle introduction the earths crust is not a solid shell. The theory of plate tectonics geology lumen learning.
Dec 19, 2017 plate tectonics is the theory that earths outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core. May be used either as learning aids for teachers of earth science or edited by earth science teachers for classroom use. The last supercontinent was pangaea that formed about 300 million years ago when the isolated continents collided. Earths geography has changed through time and continues to change today. This video briefly discusses the theory of tectonic plates, the different types of plate boundaries and their surface features. They move atop the underlying mantle, a really thick layer of hot flowing rock. The tectonic plates of the world were mapped in the second. The theory of plate tectonics grew out of earlier hypotheses and observations collected during exploration of the rocks of the ocean floor.
View plate tectonic theory, fossils, and extinction. The earths crust is divided into plates which are moved in various directions. The plates make up earths outer shell, called the lithosphere. A second significant idea derived from plate tectonic theory is that as the continents have grown through time they have alternately come together to form supercontinents, only to fragment again to form smaller isolated continents. It is made up of thick, interconnecting pieces called tectonic plates that fit together like a puzzle.
The following website contains a more detailed and lesson plans on plate tectonics, geodesy, and vlbi. At the end of the lesson, students reflect and apply their new understanding of the geosphere by examining how the earths systems interact when two plates collide. Inquiry statement scientists use evidence and models that demonstrate changes which occur from the interaction of forces that cause movements on earth. Takehome messages earths geology is dominated by the processes of plate tectonics. Principally it refers to the movement and interaction of the earths lithosphere. Continental drift and plate tectonics university of iceland. Plate movement is driven by convection in earths mantle. The theory has caused a revolution in the way we think about the earth. When the concept of seafloor spreading came along, scientists recognized that it was the mechanism to explain how continents could move around earths surface.
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. Convergence data are shown by arrows describing direction and speed, relative to the plate across the boundary. The study of how these plates move and interact and the consequences thereof is called plate tectonics from the greek word, tekton, which means. Mid1970s scientists created threedimensional images of earths interior by combining information from many earthquakes using an approach similar to computed tomography ct scanning. 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. Dec 28, 2016 find tectonic plate gis data there a few sources of freely available tectonic plate data that is available in various gis data formats such as shapefiles and kmz. Theory of continental drift is the idea that the continents have moved horizontally to their current locations. The paleomap project includes several plate tectonics animations, paleogeographic reconstructions, and animations that run the plate tectonics conveyor belt 50 million years into the future. Since the theory of plate tectonics was first introduced, how far has the tectonic plate were standing on moved. Two types of divergent plate boundaries divergent plate boundaries occur when two tectonic plates move away. Plate tectonics describes the distribution and motion of the plates.
The lithosphere is divided into plates, some of which are very large and can be entire continents heat from the mantle is the source of energy driving plate tectonics. Tectonic plates california institute of technology. The mainstream theory holds that it is the caribbean large igneous province clip which formed in the pacific ocean tens of millions of years ago. It is theorized that the hotter rock closer to the core rises while the cooler rock sinks causing a current in the form of a cycle. This includes the formation, movement, collision and destruction of plates and the resulting geological events such as seismicity, volcanism, continental drift, and. Revival of the continental drift theory wegeners theory just would not go away, despite. You will recall from a previous chapter that there are three. 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 tectonic plates theory video for kids plate tectonics is a theory of geology. In essence, platetectonic theory is elegantly simple. Wegeners theory and sea floor maps were used to develop the theory of plate tectonics. The usual theory as to the origin of the caribbean plate was confronted by a contrasting theory in 2002. 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. Continental drift evidence for continental drift a. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. Exactly how this works is still a matter of debate. Many major geological processes like volcanoes, earthquakes, mountain formation, and the arrangement of tectonic plates figure 1 are all results of plate tectonics. Plate tectonics the earths crust is divided into plates which are moved in various directions. Lithosphere is divided into plates that slide around on top of the slowly moving mesosphere tectonic plates it occurred after the breakup of pangaea, and since then the continents have drifted apart the pictures show continental drift theory from 225 million years to present. Plate tectonic theory had its beginnings in 1915 when alfred wegener proposed his theory of continental drift. New crustal plate is formed at the midocean ridges and old crustal plate is destroyed at deep ocean trenches.
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. Plate tectonics, the study of such relative motions and. Midocean ridges are essentially submerged mountain chains that are characterised by a deep central rift valley. As two adjacent plates move across the asthenosphere, they either collide, slide past another, or separate. Ocean basinsoceanic crust are continually being created and destroyed through tectonic processes. Plate tectonics is the process that drives the recycling of earths oceanic crust and the drift of continents on its surface. Crust is continuously being regenerated and removed. 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 major layers crust, mantle, core within the earth that are. Plate convergence vectors referenced from united states geological survey. This plate motion causes them to collide, pull apart, or scrape. Theory of plate tectonics is the idea that the earths crust and upper mantle are broken into sections called plates that move around on the mantle.
An updated digital model of plate boundaries, geochemistry geophysics geosystems, 43, 1027, doi. Most of the plates are composed of continental and oceanic lithosphere. Aug 06, 2012 powerpoint presentations introducing fundamental concepts and observations of plate tectonics and earthquakes. Powerpoint click to download the ms powerpoint file 146 mbytes pdf click to view or download the presentation in pdf 5 mbytes ht ml cl ick to view the presentation in html format. Plate tectonic note taking answers free pdf file sharing. Plate tectonics is the theory that explains how large pieces of the earths outermost layer, called tectonic plates, move and change shape.
Tuzo wilson offered a fundamental reinterpretation of wegeners continental drift theory and became the first person to use the term plates to describe the division and pattern of relative movement between different regions of the earths surface i. The theory of plate tectonics states that the earths solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere, the molten upper portion of the mantle. In this plate tectonic framework, large scale deformation is the local response of the lithosphere to induced stresses. Hot lithosphere generated at constructive plate boundaries loses its heat to the oceans, atmosphere and, ultimately, space by conductive cooling as it ages and spreads away from. Along spreading centers in the sea floor, melted rock rises through cracks, cools, and forms new crust that builds up midocean ridges. Find tectonic plate gis data there a few sources of freely available tectonic plate data that is available in various gis data formats such as shapefiles and kmz.
Origins of plate tectonic theory earth science resources. Iceland is one of the few places where this process can be seen on land. The theory of plate tectonics explains how plates and their continents move. Lithosphere the crust and part of the upper mantle 2.
This is a list of tectonic plates on the earths surface. Oceanic and continental plates come together, spread apart, and interact at boundaries all over the planet. Plate tectonics is the unifying theory of geology and revolutionized geology. Students then explore the plate tectonic theory and types of plate boundaries by watching a video and constructing a poster. As the atlantic ocean widened, north america and south america were pushed westward, separated for a time by oceanic crust. He also proposed a tectonic cycle the wilson cycle. Since the development of the theory, geologists have had to reexamine almost every aspect of. Tectonic plates are composed of oceanic lithosphere and. Together, these plates constitute the lithosphere, from the greek lithos, meaning rock. Plate tectonics is the theory that explains the global distribution of geological phenomena. In 2003, peter bird published a global data set of plate boundaries citation. Continental drift, sea floor spreading and plate tectonics. He had mathematical evidence to back his theory up. Chapter 1 plate tectonics power point linkedin slideshare.
Tectonic plates plate boundary referenced from bird, peter 2003 an updated digital model of plate boundaries. In 1967, mckenzie and parker suggested the theory of plate tectonics. It is explained in some detail in chapter 10, but is. The continents are carried on some of these plates. Plate tectonics is caused by heat flow within the earths interior as well as density differences between the earths crust and mantle. Plate tectonics is an expression of the thermal state of the earths interior and is the way that the earth is currently losing a large proportion of its internal heat.
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