Chapter 1 plate tectonics power point linkedin slideshare. The lithosphere includes both the crust and the solid part of the. Along spreading centers in the sea floor, melted rock rises through cracks, cools, and. Continental drift, sea floor spreading and plate tectonics. According to the theory of plate tectonics, the earths lithosphere is broken into distinct plates which are.
The theory of plate tectonics links earths internal processes to the distribution of continents and oceans. Plate tectonics have students team read pages 158 and 159 to. From wikipedia, the free encyclopedia plate tectonics from greek, tekton builder or mason describes the large scale motions of earths lithosphere. The theory encompasses the older concepts of continental drift, developed. Kings 1969b tectonic map of north america was on the basis of geosynclinal theory.
This was the time when reptiles and winged insects first appeared. L1 advanced readers plate motions point out that the arrows in figure 20 show the direction of plate motion. The concept of plate tectonics was formulated in the 1960s. The theory of plate tectonics explains how plates and their continents move. Each province is a piece of californias tectonic jigsaw puzzle. This graphic organizer for plate tectonic theory is a great way for students to organize their notes. These plates move relative to one another above a hotter, deeper, more mobile zone at average rates as great as a. In the theory of plate tectonics, the earths crust is broken into plates that move around relative to each other. The drawing above is a cross section of the earth showing the components that lie within plate tectonic theory.
Working in pairs, students think like engineers and connect what they. To help your child visualize the convection process that drives tectonic plate motion, try doing this simple experiment together. Each type of interaction causes a characteristic set of earth structures or tectonic features. 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. This plate motion causes them to collide, pull apart, or scrape. The lithosphere is broken up into seven very large continental and oceansized plates, six or seven mediumsized regional. In essence, platetectonic theory is elegantly simple.
Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. Geologists use this word to describe the forces that shape earths surface and the rock structures that form as a result. Earths geography has changed through time and continues to change today. The theory of plate tectonics geology lumen learning. The structure of the earth, plate tectonics and landforms. Midocean ridges are essentially submerged mountain chains that are characterised by a deep central rift valley. 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 theory of plate tectonics understanding main ideas label each. Two scientific advances in the mid20th century resulted in information critical to acceptance of continental drift and plate tectonic theory. A middle school lesson on plate tectonics theory for grades 68. 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. Plate tectonics information and facts national geographic. Together, these plates constitute the lithosphere, from the greek lithos, meaning rock. As a result of this movement, three types of plate boundaries are formed.
Continental drift theory alfred wegener, 1922 plate tectonics breakup of pangea. When the concept of seafloor spreading came along, scientists recognized that it was the mechanism to explain how continents could move around earths surface. The theory of plate tectonics continued introduction 1. The earth surface has continuously been changing ever since it was formed, especially regarding the geomorphological and geological phenomena. According to the generally accepted platetectonics theory, scientists believe that earths surface is broken into a number of shifting slabs or plates, which average about 50 miles in thickness. The earth is the only planet known to currently have plate tectonics. Plate tectonics by combining the sea floor spreading theory with continental drift and information on global seismicity, the new theory of plate tectonics became a coherent theory to explain crustal movements. Wegeners theory and sea floor maps were used to develop the theory of plate tectonics. Plate tectonic concepts made all earlier tectonic maps obsolete. Continental drift and plate tectonics university of iceland. Revival of the continental drift theory wegeners theory just would not go away, despite.
Students gather evidence to explain the theory of plate tectonics. Plate tectonics is the theory that explains the global distribution of geological phenomena. Then have them reread to identify observations that the theory of plate tectonics explains. Plate tectonics is the movement of lithospheric plates relative to each other. The theory has caused a revolution in the way we think about the earth.
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. Central to the theory of plate tectonics is the concept of. Convection current theory cct convection current theory forms the basis of sfst and pt. Continental drift theory continental drift is the hypothesis that all the continents had once been joined together in a single landmass. Introduction to plate tectonic theory, geodesy, and vlbi.
The plates make up earths outer shell, called the lithosphere. The cross section should really be curved to correspond. The theory of plate tectonics activityworksheet 3 volcanoes 8. This includes the formation, movement, collision and destruction of plates and the resulting geological events such as seismicity, volcanism, continental drift, and.
Plate tectonics reveals that the lithosphere is divided into eight major pieces plates with several smaller plates fig. Plate tectonicsthe unifying theory of geology geology. Plate tectonics is a theory developed in the late 1960s, to explain how. Since the development of the theory, geologists have had to reexamine almost every aspect of. 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.
Demonstrating the movement of the earths crust and how tectonic plates interact at plate boundaries 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. The plates are mobile, moving in constant, slow motion measured in rates of centimeters per year. The theory of plate tectonics worksheet teachengineering. From continental drift to plate tectonics 7 and therefore they could not sink to become ocean basins. Tectonic theories attempt to explain why mountains, earthquakes, and. Plates are composed of lithosphere, about 100 km thick, that float on the ductile asthenosphere. New crustal plate is formed at the midocean ridges and. Plate tectonic theory had its beginnings in 1915 when alfred wegener proposed his theory of continental drift. First, the topography of the ocean floor was mapped in great detail during and after world war ii. Principally it refers to the movement and interaction of the earths lithosphere. Looking at the information you compiled in your chart above, explain one way the theory of plate tectonics can relate to engineering. Each major piece of cracked crust is called a tectonic plate figure 22. 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.
Observations that led to the development of plate tectonic theory. First, gather a bottle of food coloring and a large, clear glass container. They also look at how volcanoes and earthquakes are explained by tectonic plate movement, and how engineers use this information. The lithosphere is broken up into what are called tectonic plates in the. Third, and most fundamental, physicists discovered radiogenic heat, which contradicted the basic assumption. Using the online resources at the earthquakes living lab, students examine information and gather evidence supporting the theory. Earths surface is made up of rigid slabs of rock, or plates, which move with respect to each other constant motion tectonic. The continents are carried on some of these plates. 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. You will recall from a previous chapter that there are three. Large pieces of the lithosphere that float on the asthenosphere are called.
Plate tectonics describes the distribution and motion of the plates. Theory of continental drift proposed by alfred wegener in 1912, but not widely accepted until seafloor spreading was discovered in 1960. Plate tectonics the earths crust is divided into plates which are moved in various directions. Along the way, i disclose details of what real science is all about, details all too often absent in textbooks and classroom discussions. 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. 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 overview of plate tectonics provides a view of the big picture of californias geologic heritage. Plate tectonic theory recognizes that the lithosphere is broken into plates, jigsaw like pieces of various sizes.
Plates can include both oceanic and continental lithosphere and drift across earths surface floating on the partially molten asthenosphere. Tectonic plates are composed of oceanic lithosphere and. Ocean basinsoceanic crust are continually being created and destroyed through tectonic processes. The new model of horizontal movement of the continents was called plate tectonics. Plate tectonic theory plate tectonic theory recognizes that the lithosphere is broken into plates, jigsawlike pieces of various sizes. Plate tectonic theory arose out of the hypothesis of continental drift. In 1967, mckenzie and parker suggested the theory of plate tectonics.
212 1133 635 837 16 1323 210 547 1271 633 471 641 1465 1500 832 1479 1377 970 316 710 1541 1194 1639 315 1643 1256 1193 1645 1446 1486 104 258 1580 1214 848 1568 1161 864 1142 905 391 152 944 70 940 1340 127