The first two sections of the chapter reveal the basic observations that were used to make predictions on the geologic processes that shaped the face of earth. Pdf continental drift and the theory of plate tectonics k. The surface of the earth is divided into a number of rigid plates that extend from the surface to the base of the lithosphere. Plate tectonic theory satellite images have provided evidence for plate tectonics by showing the geologic features that form at the boundaries between tectonic plates. 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. The drawing above is a cross section of the earth showing the. As plates move, the new crust gradually moves away from the ridge. Tectonic plates are pieces of the lithosphere, which is a layer of brittle rock that corresponds to the crust and the upper lab 2. Toward an integrated physical and chemical theory paul j. The major mountainbuilding idea that was supported from the 19 th century and into the 20 th is the geosynclinal theory. Plate tectonics kean university pdf book manual free. 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. Plate tectonics is a theory developed in the late 1960s, to explain how the outer layers of the. Earths lithosphere is broken into separate sections called plates.
Prior to the year 1900, most scientists that studied geology believed that the present position and shape of. Plates are composed of the crust and a part of the upper mantle, these two parts together are called the lithosphere. These plates are floating on magma and moving around as a result. The theory of plate tectonics describes how the plates move, interact, and change the physical landscape. The earths plates jostle about in fits and starts that are punctuated with earthquakes and volcanic eruptions. The plate tectonics gizmo shows a crosssection, or side view, of earth. Choose from 232 different sets of 7th grade science chapter 7 plate tectonics theory flashcards on quizlet. In 1967, mckenzie and parker suggested the theory of plate tectonics. In the early 1960s, the emergence of the theoryof plate tectonicsstarted a revolution in the earth sciences. The structure of the earth, plate tectonics and landforms. Geosynclinal theory the emergence and evolution of plate. Marvin herndon transdyne corporation san diego, california 921 usa september 30, 2005 abstract textbooks frequently extol plate tectonics theory without questioning what might be wrong with the theory or without discussing a competitive theory. It is shown that the idea of mantlewide convection, as well as.
The san andreas fault right is slowly pulling southern california and part of western. 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. 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. For more information on how to use these and other tools, see appendix a. Plate tectonics is the theory that explains how large pieces of the earths outermost layer, called tectonic plates, move and change shape. Specific contributions to plate tectonic theory or geophysics. The theory of plate tectonics explains the formation, movement, and subduction of earths plates. Seafloor spreading helps explain continental drift in the theory of plate tectonics. As scientists learned more about seafloor spreading and magnetic reversals, they formed a theory to explain how continents move. The theory of plate tectonics activityworksheet 3 volcanoes 8. 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. Continental drift and the development of plate tectonic theory.
Plate tectonic theory arose out of the hypothesis of continental drift proposed by alfred. The theory of plate tectonics states that earths lithosphere is broken. The lithosphere lithosphere is comprised of the upper mantle and the. 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.
Chapter 1 from continental drift to plate tectonics naomi oreskes since the l6th century, cartographers have noticed the jigsawpuzzle fit of the continental edges. The following website contains a more detailed and lesson plans on plate tectonics, geodesy, and vlbi. 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. We now know that, directly or indirectly, plate tectonics influences nearly. The key principle of plate tectonics is that the lithosphere exists as separate and distinct tectonic plates, which ride on the. Suess is credited for generating many of the concepts that led to the theory of plate tectonics and paleogeography. Plate tectonics information and facts national geographic. Plate tectonics is the unifying theory of the earth how did the theory develop. 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. Although plate tectonics is a relatively young idea in comparison with unifying theories from other sciences e. Describe the historical development of evidence that supports plate tectonic theory. 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 reversals, midocean ridges, transform faults, and seafloor spreading.
Introduction to plate tectonic theory, geodesy, and vlbi. 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. 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. Plate tectonics is the surface manifestation of mantle convection. The theory has caused a revolution in the way we think about the earth. However, the physics of plate tectonics is poorly understood. He suggested that germany could ease its debths after wwi by extracting gold from sea water theoretically up to 56 mg of gold can be extracted from 1 m3 of sea water. According to the theory of plate tectonics, the earths lithosphere is broken into distinct plates which are. 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. Convection currents rise in the asthenosphere and spread out beneath the lithosphere, causing the movement of earths plates. Notes on plate tectonics plate tectonics states that the earths crust and upper mantle are broken into sections, called plates. East africas great rift valley left is so large it can be seen from space.
Earths geography has changed through time and continues to change today. A plate can comprise both oceanic and continental lithosphere. In addition, the diving plate melts and is often spewed out in. 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. Together these concepts would become the theory of plate tectonics. Plate tectonics is a unifying theory for geology unifying theory 2plate tectonics unifying theory plate tectonics describe movement of continental and oceanic plates and forces driving them it explains locations of mountain chains, earthquakes, rock assemblages, and structures on sea floor for geology plate tectonics is similar in. The earth surface has continuously been changing ever since it was formed, especially regarding the geomorphological and geological phenomena. Overview continental drift, in the context of the modern theory of plate tectonics, is explained by the movement of lithospheric plates over the asthenosphere. Since the development of the theory, geologists have had to reexamine almost every aspect of.
Mobi the theory of plate tectonics worksheet answers. The layer below the lithosphere is the asthenosphere. Using examples, explain the theory of plate tectonics. 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. Ocean basinsoceanic crust are continually being created and destroyed through tectonic processes.
Frisch and meschede and blakey answer all these questions and more through the presentation and explanation of the geodynamic processes upon which the theory of continental drift is based and which have led to the concept of plate tectonics. By definition, the word plate in geologic terms means a large slab of solid rock. The theory of plate tectonics tek tahn iks states that pieces of earths lithosphere are in slow, const ant motion, driven by convection currents in the mantle. Seafloor spreading occurs at divergent plate boundaries which subsequently create midocean ridges. Locations of earthquakes and volcanoes show the plate boundaries and ocean floor features. Looking at the information you compiled in your chart above, explain one way the theory of plate tectonics can relate to engineering. Pdf the main problems of the plate tectonics model are discussed in the paper. All this evidence, both from the ocean floor and from the continental margins, made it clear around 1965 that continental drift was feasible and the theory of plate tectonics, which was defined in a series of papers between 1965 and 1967, was born, with all its extraordinary explanatory and predictive power. Like the scientists before us, we will now merge the ideas of continental drift and seafloor spreading into the theory of plate tectonics. New oceanic crust is formed through magma rising through the gap and cooling. Plate tectonicsthe unifying theory of geology geology.
This plate motion causes them to collide, pull apart, or scrape against each other. Plate tectonics is the surface manifestation of mantle convection, but the large contrast in viscosities between the lithosphere and the deeper mantle leads to departures from a simple boiling pot. Geomorphology and plate tectonics geogem note 2 boundaries of the geomorphic provinces that we deine in this report as coastline. The theory of plate tectonics provides an example of the evolution of scientific thought. 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 theory of plate tectonics key concepts what is the theory of plate tectonics. Central to the theory of plate tectonics is the concept of. The concept of plate tectonics was formulated in the 1960s. The theory of plate tectonics geology lumen learning. Continental drift, sea floor spreading and plate tectonics. 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. Although hapgoods theory of earth crust displacement attempts to answer unsolved mysteries in cartography and archaeology through geologic means, the evidence for the theory itself is lacking in validity, and instead of providing a geologically sound addition to plate tectonics, the theory posed is riddled by logical and factual gaps. Plate tectonics causes thermal and fertility variations in the mantle and stress variations in the plates, thus obviating the need for extraneous assumptions about the. Learn 7th grade science chapter 7 plate tectonics theory with free interactive flashcards.
What are the three types of tectonic plate boundaries. 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 states that the crust lithosphere is broken into 16 big slabs called plates. In the frame of plate tectonics several models have been constructed on its unproved assumption. Since the theory of plate tectonics was first introduced, how far has the tectonic plate were standing on moved. Plate tectonics plate tectonics is the unifying theory of geology and revolutionized geology cornerstone of earthsystem approach. Tackley plate tectonics and convection of the solid, rocky mantle are responsible for transporting heat out of earth.
Each type of interaction causes a characteristic set of earth structures or tectonic features. Plate tectonics thus provides the big picture of geology. Though the faces of the earth did not include much original work, seuss demonstrated a great ability to synthesize work into the bigger picture. When the concept of seafloor spreading came along, scientists recognized that it was the mechanism to explain how continents could move around earths surface. Pdf critical analysis of the plate tectonics model and causes of. Tectonic plates are composed of oceanic lithosphere and. At plate boundaries, plates collide, move apart, move under or over each other, or slide past one another. 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 the earths crust is divided into plates which are moved in various directions. The story on the discovery of the mid ocean ridges starts with fritz haber, a prominent german chemist nobel prize in chemistry in 1918.
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