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. In essence, platetectonic theory is elegantly simple. Plate tectonics tectonic plates theory video for kids plate tectonics is a theory of geology. In the frame of plate tectonics several models have been constructed on its unproved assumption. Tectonic plates are composed of oceanic lithosphere and.
Each type of interaction causes a characteristic set of earth structures or tectonic features. Plate tectonics, the study of such relative motions and. Principally it refers to the movement and interaction of the earths lithosphere. 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. Origins of plate tectonic theory earth science resources. This plate motion causes them to collide, pull apart, or scrape. Locations of earthquakes and volcanoes show the plate boundaries and ocean floor features.
The usual theory as to the origin of the caribbean plate was confronted by a contrasting theory in 2002. Theory of continental drift is the idea that the continents have moved horizontally to their current locations. It is made up of thick, interconnecting pieces called tectonic plates that fit together like a puzzle. 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.
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. 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. Watch the plate tectonics explained youtube clip and have a go at explaining what plate tectonics are in your own words. Midocean ridges are essentially submerged mountain chains that are characterised by a deep central rift valley.
New crustal plate is formed at the midocean ridges and old crustal plate is destroyed at deep ocean trenches. Most of the plates are composed of continental and oceanic lithosphere. Takehome messages earths geology is dominated by the processes of plate tectonics. 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. 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 surface of the earth is divided into a number of rigid plates that extend from the surface to the base of the lithosphere. 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. The following website contains a more detailed and lesson plans on plate tectonics, geodesy, and vlbi. Plate tectonics describes the distribution and motion of the plates. 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. The structure of the earth, plate tectonics and landforms. The tectonic plates of the world were mapped in the second. Iceland is one of the few places where this process can be seen on land.
Sep 17, 2009 the theory of plate tectonics explains how plates and their continents move. In part 1 of this activity, students are provided with a blank topographic profile and an associated tectonic plate boundary map. The theory of plate tectonics geology lumen learning. When using the powerpoint slides as a learning resource, it is important to read the notes that accompany. 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. 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.
As the atlantic ocean widened, north america and south america were pushed westward, separated for a time by oceanic crust. As two adjacent plates move across the asthenosphere, they either collide, slide past another, or separate. Earths geography has changed through time and continues to change today. He also proposed a tectonic cycle the wilson cycle. Two types of divergent plate boundaries divergent plate boundaries occur when two tectonic plates move away. In 2003, peter bird published a global data set of plate boundaries citation.
Along spreading centers in the sea floor, melted rock rises through cracks, cools, and forms new crust that builds up midocean ridges. Students then explore the plate tectonic theory and types of plate boundaries by watching a video and constructing a poster. 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. Introduction to plate tectonic theory, geodesy, and vlbi. 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. 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. The continents are carried on some of these plates. 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. Many major geological processes like volcanoes, earthquakes, mountain formation, and the arrangement of tectonic plates figure 1 are all results of plate tectonics. 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. Development of plate tectonic theory timeline preceden. Plate movement is driven by convection in earths mantle. Wegener believed that all of the continents were connected as one large land mass he called pangea about 200 million years ago.
The new model of horizontal movement of the continents was called plate tectonics. 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. 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. The plates make up earths outer shell, called the lithosphere.
A synopsis of plate tectonics james madison university. Plate tectonic note taking answers free pdf file sharing. Tectonic plates are pieces of earths crust and uppermost mantle, together referred to as the lithosphere. The last supercontinent was pangaea that formed about 300 million years ago when the isolated continents collided.
It is explained in some detail in chapter 10, but is. Plate tectonics is caused by heat flow within the earths interior as well as density differences between the earths crust and mantle. 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 the concept of seafloor spreading came along, scientists recognized that it was the mechanism to explain how continents could move around earths surface. This video briefly discusses the theory of tectonic plates, the different types of plate boundaries and their surface features. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. This technique, now known as seismic tomography, enables scientists to. Lithosphere the crust and part of the upper mantle 2. 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. Revival of the continental drift theory wegeners theory just would not go away, despite. Mar 01, 2016 this video briefly discusses the theory of tectonic plates, the different types of plate boundaries and their surface features. Plate tectonics simple english wikipedia, the free. He had mathematical evidence to back his theory up.
The theory of plate tectonics explains how plates and their continents move. Earths crust and upper mantle are divided into plates. Plate tectonics is the process that drives the recycling of earths oceanic crust and the drift of continents on its surface. 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. Plate tectonics is the theory that explains how large pieces of the earths outermost layer, called tectonic plates, move and change shape. Crust is continuously being regenerated and removed. 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. Ocean basinsoceanic crust are continually being created and destroyed through tectonic processes. This plate motion causes them to collide, pull apart, or scrape against each other. 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. 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. Plate tectonics is the unifying theory of geology and revolutionized geology.
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. In this plate tectonic framework, large scale deformation is the local response of the lithosphere to induced stresses. 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. Central to the theory of plate tectonics is the concept of. The plates are around 100 km 62 mi thick and consist of two principal types of material. The crust is made up of six major plates and a number of minor ones. Tectonic plates plate boundary referenced from bird, peter 2003 an updated digital model of plate boundaries. Plate tectonics is the theory that explains the global distribution of geological phenomena. Powerpoint presentations introducing fundamental concepts and observations of plate tectonics and earthquakes.
Plate convergence vectors referenced from united states geological survey. This includes the formation, movement, collision and destruction of plates and the resulting geological events such as seismicity, volcanism, continental drift, and. 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. Tectonic plates california institute of technology. Against plate tectonics on earth the plate tectonics theory. 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. Aug 06, 2012 powerpoint presentations introducing fundamental concepts and observations of plate tectonics and earthquakes. An updated digital model of plate boundaries, geochemistry geophysics geosystems, 43, 1027, doi. The earths crust is divided into plates which are moved in various directions. Continental drift and plate tectonics university of iceland.
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. Exactly how this works is still a matter of debate. The study of how these plates move and interact and the consequences thereof is called plate tectonics from the greek word, tekton, which means. The currents would be at parts parallel to giant plates on the surface and carry them. They move atop the underlying mantle, a really thick layer of hot flowing rock. Since the development of the theory, geologists have had to reexamine almost every aspect of. Wegeners theory and sea floor maps were used to develop the theory of plate tectonics. Mid1970s scientists created threedimensional images of earths interior by combining information from many earthquakes using an approach similar to computed tomography ct scanning. Convergence data are shown by arrows describing direction and speed, relative to the plate across the boundary. Plate tectonic theory had its beginnings in 1915 when alfred wegener proposed his theory of continental drift. View plate tectonic theory, fossils, and extinction.
The theory has caused a revolution in the way we think about the earth. A plate can comprise both oceanic and continental lithosphere. 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. 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.
Continental drift evidence for continental drift a. Plate tectonics the earths crust is divided into plates which are moved in various directions. A plate tectonic puzzle introduction the earths crust is not a solid shell. Plate tectonics information and facts national geographic. Inquiry statement scientists use evidence and models that demonstrate changes which occur from the interaction of forces that cause movements on earth. Plate tectonic theory arose out of the hypothesis of continental drift proposed by. The evolution of plate tectonics article pdf available in philosophical transactions of the royal society a mathematical physical and engineering sciences 37622. The theory of plate tectonics grew out of earlier hypotheses and observations collected during exploration of the rocks of the ocean floor. Together, these plates constitute the lithosphere, from the greek lithos, meaning rock.
Since the theory of plate tectonics was first introduced, how far has the tectonic plate were standing on moved. Students are asked to draw a schematic crosssection on the profile down to the asthenosphere including tectonic plates with relative thicknesses of crust etc. May be used either as learning aids for teachers of earth science or edited by earth science teachers for classroom use. Continental drift, sea floor spreading and plate tectonics. Below this is a zone that slows earthquake waves because the mantle here is plastic rather than brittle.966 206 585 517 577 741 470 1156 384 1532 771 307 1282 63 76 1341 20 1646 483 854 1497 1296 1366 449 1029 321 608 59 1244 511 656 437 1121 878 397