Since the development of the theory, geologists have had to reexamine almost every aspect of. Pdf alfred wegenerfrom continental drift to plate tectonics. Continentcontinent boundaries these form when continental lithosphere on one plate. 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. 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. However, the physics of plate tectonics is poorly understood. According to plate tectonic theory, the lithosphere is divided into rigid plates that interact with one another at their boundaries. Earths geography has changed through time and continues to change today. Plate tectonics is the theory that explains how large pieces of the earths outermost layer, called tectonic plates, move and change shape. Third, and most fundamental, physicists discovered radiogenic heat, which contradicted the basic assumption of contraction theory that the earth was steadily cooling. Plate tectonics the earths crust is divided into plates which are moved in various directions. We now know that, directly or indirectly, plate tectonics influences nearly all geologic processes, past and present. The theory of plate tectonics links earths internal processes to the distribution of continents and oceans. Plate tectonics is a theory developed in the late 1960s, to explain how the outer layers of the.
Looking at the information you compiled in your chart above, explain one way the theory of plate tectonics can relate to engineering. 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. From wikipedia, the free encyclopedia plate tectonics from greek, tekton builder or mason describes the large scale motions of earths lithosphere. The plates are mobile, moving in constant, slow motion measured in rates of centimeters per year.
There are three different types of convergent boundaries. Plate tectonics is the theory that explains the global distribution of geological phenomena. Plate tectonics next after the 2nd world war seismic measuring instruments were set up all around the world, initially to check for nuclear weapons testing. The greatest revolution in 20th century understanding of how our planet works, known as plate tectonics, happened in the 1960s, and has been so profound that it can be likened to the huge advances in physics that followed einsteins theory of relativity. Continental drift and the theory of plate tectonics.
According to the theory of plate tectonics, the earths surface is divided into rigid. Convection current theory cct convection current theory forms the basis of sfst and pt. 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. Earthquakes, faults, and folds take place at these boundaries. New oceanic crust is formed through magma rising through the gap and cooling. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. At plate boundaries, plates collide, move apart, move under or over each other, or slide past one another.
Plate tectonics the tectonic plates of the world were mapped in the second half of the 20th century. Earths crust and upper mantle are broken into sections. Toward an integrated physical and chemical theory paul j. 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. East africas great rift valley left is so large it can be seen from space. Continental drift theory alfred wegener, 1922 plate tectonics breakup of pangea. This graphic organizer for plate tectonic theory is a great way for students to organize their notes. Theory of plate tectonics worksheet answer key worksheet. The new model of horizontal movement of the continents was called plate tectonics. What evidence did scientists find in the himalayas that support the theory of plate tectonics. Plate tectonic theory recognizes that the lithosphere is broken into plates, jigsaw like pieces of various sizes. Plate tectonics also enabled geologists to explain the origins of the oceanic crust and the continents.
In geologic terms, a plate is a large, rigid slab of solid rock. In this plate tectonic framework, large scale deformation is the local response of the lithosphere to induced stresses. 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. Putting these two words together, we get the term plate tectonics, which refers to how the earths surface is built of plates.
You will recall from a previous chapter that there are three major layers crust, mantle, core within the earth that are. A plate can comprise both oceanic and continental lithosphere. The word tectonics comes from the greek root to build. 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. 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. Third, and most fundamental, physicists discovered radiogenic heat, which contradicted the basic assumption of contraction theory. The earth is the only planet known to currently have plate tectonics. Development of plate tectonic theory timeline preceden. Plate tectonic theory satellite images have provided evidence for plate tectonics by showing the geologic features that form at the boundaries between tectonic plates. According to the theory of plate tectonics, the earths lithosphere is broken into distinct plates which are. Full and real axiomatic system of plate tectonics 22 d.
The concept of plate tectonics was formulated in the 1960s. Plate tectonicsthe unifying theory of geology geology. This plate motion causes them to collide, pull apart, or scrape against each other. Plate tectonics describes the distribution and motion of the plates. In 1967, mckenzie and parker suggested the theory of plate tectonics. 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 plate tectonics gizmo shows a crosssection, or side view, of earth. Locations of earthquakes and volcanoes show the plate boundaries and ocean floor features. The theory of plate tectonics key concepts filename. This plate motion causes them to collide, pull apart, or scrape. The theory of plate tectonics grew out of earlier hypotheses and observations collected during exploration of the rocks of the ocean floor. The structure of the earth, plate tectonics and landforms. Ocean basinsoceanic crust are continually being created and destroyed through tectonic processes.
The theory of plate tectonics activityworksheet 3 volcanoes 8. Principally it refers to the movement and interaction of the earths lithosphere. The following website contains a more detailed and lesson plans on plate tectonics, geodesy, and vlbi. Plate tectonics pt plate tectonics is the movement of lithospheric plates relative to each other. Continental drift and the development of plate tectonic theory. Section 3 theory of plate tectonics key free pdf file. By definition, the word plate in geologic terms means a large slab of solid rock. New crustal plate is formed at the midocean ridges and old crustal plate. 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. Interactive textbook 124 plate tectonics section 3 name class date the theory of plate tectonics continued convergent boundaries a convergent boundary forms where plates are moving together. Plates are composed of lithosphere, about 100 km thick, that float on the ductile asthenosphere. Continental drift, sea floor spreading and plate tectonics.
Scientists do not know for sure what causes tectonic plates to move. 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. The continents are carried on some of these plates. Students gather evidence to explain the theory of plate tectonics. Indeed, the notion that the entire earths surface is continually shifting has profoundly changed the way we. The theory encompasses the older concepts of continental drift, developed. Although plate tectonics is a relatively young idea in comparison with unifying theories from other sciences e. Seafloor spreading helps explain continental drift in the theory of plate tectonics. 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. From continental drift to plate tectonics 7 and therefore they could not sink to become ocean basins. Though the faces of the earth did not include much original work, seuss demonstrated a great ability to synthesize work into the bigger picture. Plate tectonics a theory founded on circular arguments. Theory of plate tectonics worksheet answer key section 3. The theory of plate tectonics geology lumen learning.
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. The sections, called plates, move on a plasticlike layer of the mantle. The plasticlike layer below the lithosphere is called the asthenosphere. Central to the theory of plate tectonics is the concept of. The crust is made up of six major plates and a number of minor ones. Interactive textbook 125 plate tectonics section 3 name class date the theory of plate tectonics continued why do tectonic plates move. Above the cross section is a birdseye view of the same location. The grade 6 earth science unit on plate tectonics is presented to students through a series of investigations using indirect evidence models and direct evidence, experiments, active learning experiences, researching using a variety of sources, questions, and assessments. Each major piece of cracked crust is called a tectonic plate figure 22. Tackley plate tectonics and convection of the solid, rocky mantle are responsible for transporting heat out of earth. 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. This includes the formation, movement, collision and destruction of plates and the resulting geological events such as seismicity, volcanism, continental drift, and. The theory of plate tectonics combine which two other theories.
The earth surface has continuously been changing ever since it was formed, especially regarding the geomorphological and geological phenomena. History of plate tectonics plate tectonic theory had its beginnings in 1915 when alfred wegener proposed his theory of continental drift. Plate tectonics overview the earths crust is cracked like the shell of a hardboiled egg. Suess is credited for generating many of the concepts that led to the theory of plate tectonics and paleogeography. Introduction to plate tectonic theory, geodesy, and vlbi. The theory of plate tectonics key concepts what is the theory of plate tectonics.
This missing piece of the puzzle helped put it all together into one theory plate tectonics. Plate movements are responsible for most continental and ocean floor features and for the distribution of most rocks and minerals within earths crust. Plate tectonics thus provides the big picture of geology. 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. Incomplete, officially presented axiomatic system of plate tectonics 21 c. The surface of the earth is divided into a number of rigid plates that extend from the surface to the base of the lithosphere. Indeed, the notion that the entire earths surface is continually shifting has profoundly changed the way we view our world. 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. They also look at how volcanoes and earthquakes are explained by tectonic plate movement, and how engineers use this information.
You will recall from a previous chapter that there are three. The theory has caused a revolution in the way we think about the earth. Continental drift and plate tectonics university of iceland. In the early 1900s alfred wegener proposed the continents were drifting. The theory of plate tectonics the theory of plate tectonics this section explains how the lithosphere is broken into separate sections that move. Plate tectonicsthe unifying theory of geology geology u. According to the theory, earth has a rigid outer layer, known as the lithosphere, which is typically about 100 km 60 miles thick and overlies a plastic moldable, partially molten layer called the asthenosphere. 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.
Learn 7th grade science chapter 7 plate tectonics theory with free interactive flashcards. Demonstrating the movement of the earths crust and how tectonic plates interact at plate boundaries the theory of plate tectonics. In the 1960s new evidence and ideas about the earths crust developed these hypotheses into the theory of plate tectonics, which states that the lithosphere is composed of a few large and several small plates that move slowly across the asthenosphere, and that intense geologic activity, such as volcanoes and earthquakes, occur at plate. Choose from 232 different sets of 7th grade science chapter 7 plate tectonics theory flashcards on quizlet. The instruments also sensed the movement of tectonic plates.
Plate tectonic theory arose out of the hypothesis of continental drift proposed by alfred. Scientists found evidence from molten material, magnetic stripes, and drilling samples to back up wegeners theory. 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. Seafloor spreading occurs at divergent plate boundaries which subsequently create midocean ridges. Each type of interaction causes a characteristic set of earth structures or tectonic features. How can students be taught to question prevailing, currently popular theories if they are only presented a onesided view. Working in pairs, students think like engineers and connect what they. Using the online resources at the earthquakes living lab, students examine information and gather evidence supporting the theory.
As plates move, the new crust gradually moves away from the ridge. It has since been incorporated into the theory of plate tectonics, a wider theory of plate motion. Plate tectonics reveals that the lithosphere is divided into eight major pieces plates with several smaller plates fig. The theory of plate tectonics worksheet teachengineering.
The theory of plate tectonics explains the formation, movement, and subduction of earths plates. The drawing above is a cross section of the earth showing the components that lie within plate tectonic theory. Seafloor and continents move around on earths surface, but what is actually moving. Specific contributions to plate tectonic theory or geophysics suess is credited for generating many of the concepts that led to the theory of plate tectonics and paleogeography. 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. The theory of plate tectonics states that the earths outermost layer is fragmented into a dozen or more large and small plates that are moving. Specific contributions to plate tectonic theory or geophysics. The san andreas fault right is slowly pulling southern california and part of western. The earths crust is divided into plates which are moved in various directions. Pdf continental drift and the theory of plate 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. Plate tectonics as a paradigm, trying to shape geology like quantum mechanics 20 a. Earths lithosphere is broken into separate sections called 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. Alfred wegenerfrom continental drift to plate tectonics article pdf available in resonance 106. The theory of plate tectonics explains the past and current movements of the rocks at earths surface lithospheric plates and provides a framework for understanding its geological history. However, over the past 50 years, scientists have used the theory of continental drift to develop the current theory the theory of plate tectonics. The theory of plate tectonics describes how the plates move, interact, and change the physical landscape.
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