Plate tectonics is an expression of the convective regime in the underlying mantle, but the link between individual convection cells and plate boundaries is not direct because plate boundaries are not fixed and, like the plates, move relative to one another. Mountains form and earthquakes shake at tectonic plate boundaries, where new landforms rise and fall. Divergent boundaries constructive are where plates are moving away from each other. The earth is the only planet known to currently have plate tectonics. Under the plates is a weaker layer of partially melted rock. They move at a rate of one to two inches three to five centimeters per year. The theory has caused a revolution in the way we think about the earth. The theory of plate tectonics geology lumen learning.
The structure of the earth, plate tectonics and landforms. The theory of plate tectonics grew out of earlier hypotheses and observations. The lithosphere is divided into plates, some of which are very large and can be entire continents. The theory of plate tectonics grew out of earlier hypotheses and observations collected during exploration of the rocks of the ocean floor. You will recall from a previous chapter that there are three major layers crust, mantle, core within the earth that are. Plate tectonic theory arose out of the hypothesis of continental drift proposed by. Plate tectonics is caused by heat flow within the earths interior as well as density differences between the earths crust and mantle. We now know that, directly or indirectly, plate tectonics influences nearly all geologic processes, past and present. 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. Following the recognition of magnetic anomalies defined by. Plate tectonics definition of plate tectonics by the free. A fault is a break in the rocks that make up the earths crust, along which on either side rocks move pass eachother. This section will introduce you to the concept of plate tectonics, how it works, why it is important and how it is shaping the world today.
Study 16 terms plate tectonics definition flashcards. Indeed, the notion that the entire earths surface is continually shifting has profoundly changed the way we view our world. Plate tectonics definition and meaning collins english. In 1977, after decades of tediously collecting and mapping ocean sonar data, scientists began to see a fairly accurate picture of the seafloor emerge. Pdf plate tectonics, our major paradigm for how the earth works, was established in the. Plate techtonics synonyms, plate techtonics pronunciation, plate techtonics translation, english dictionary definition of plate techtonics. The lithosphere, defined as the rigid outer shell of the earth roughly 100 km thick. Describe and compare different types of plate motions, rates of motion and the driving mechanisms and forces involved with each. As the plates pull apart, hot molten material can rise up this newly formed pathway to the surface causing volcanic activity.
Plate boundary definition of plate boundary by medical. Plate tectonics definition of plate tectonics by merriam. Reading strategy comparing and contrasting after you read, compare the three types of plate boundaries by completing the table. In geologic terms, a plate is defined based on mechanical and.
This plate motion causes them to collide, pull apart, or scrape. At divergent boundaries in the oceans, magma from deep in the earths mantle rises toward the surface and pushes apart two or more plates. In 1967, mckenzie and parker suggested the theory of plate tectonics. Second, two plates may come together, at a converging plate boundary. 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. Tectonics definition, the science or art of assembling, shaping, or ornamenting materials in construction. Introduction to plate tectonics discovery education.
Study 16 terms plate tectonics definition flashcards quizlet. 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. The san andreas fault is a transform fault, a kind common on the sea floor but rarely found on land. Plate tectonics definition, a theory of global tectonics in which the lithosphere is divided into a number of crustal plates, each of which moves on the plastic asthenosphere more or less independently to collide with, slide under, or move past adjacent plates. Earthquakes and volcanoes are examples of grelacslea largescale ssmtye system aetrstnoiicn interactions. Today, these theories serve as the foundation upon. Plate tectonics vocabulary marcias science teaching ideas. Plate tectonics is the way that large pieces of the earths surface move slowly around. Continental drift and plate tectonics university of iceland. Plate tectonics article about plate tectonics by the. Continental drift, sea floor spreading and plate tectonics. According to the theory of plate tectonics, the earths lithosphere is broken into distinct. Because the basic feature of plate tectonics is its circular argumentative structure. The theory, or idea, of plate tectonics says that earth s outer layer is made up of large, moving pieces called plates.
Volcanoes form between the plates, as magma rises upward from the underlying mantle. This is largely due to the fact that it was the first major geologic theory seeded in the united states. But learning about it during the last 40 years has given scientists many theoretical tools to understand other planets, even those that circle other stars. Plate tectonics from the late latin tectonicus, from the greek. The tharpheezen map illustrated the geological features that characterize the seafloor and became a crucial factor in the acceptance of the theories of plate tectonics and continental drift. Plate techtonics definition of plate techtonics by the free. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Plate tectonics, the study of such relative motions and their consequences, allows relating surface, geological and geophysical structures with quantified movements attributed to deep processes of the earths heat engine. Plate tectonics simple english wikipedia, the free. Plate tectonics is the most important concept in modern geology. 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. At diverging plate boundaries, earthquakes occurs as the plates pull away from each other. Two situations are possible at converging plate boundaries. Plate techtonics definition of plate techtonics by the.
Plate movements are responsible for most continental and ocean floor features and for the distribution of most rocks and minerals within earths crust. Investigating the patterns produced by volcanoes and earthquakes. Discover the concept of plate tectonics and how shifting plates affect our planet. Plate tectonics vocabulary lithospheric plates plate tectonics lithosphere asthenosphere continental drift seafloor spreading diverging boundaries sliding boundaries.
A fault line is the trace of a fault, or the line of intersection between the fault line and the earths surface. 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 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. The movement of the plates creates three types of tectonic boundaries. Convergent boundaries destructive are where plates are moving towards each. The fundamental concepts for geosynclinal theory were introduced in james halls presidential address for the geological society of america at the meeting of the american association for the advancement of science at montreal in 1857 knopf, 649. At the turn of the century, geosynclinal theory led the field of tectophysics. 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.
Tectonic plates are huge pieces of hheoiterpsl lithosphere that slowly move on the hhtnseseproae asthenosphere. Stikeslip faults are vertical or nearly vertical fractures where the blocks have mostly moved horizontally. Convection currents happen because the hotter material is less dense and rises. Plate tectonics is the central unifying theory for. 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. Jan, 2010 in plate tectonics, a divergent boundary is a linear feature that exists between two tectonic plates that are moving away from each other. Geosynclinal theory the emergence and evolution of plate. These areas can form in the middle of continents or on the ocean floor. In plate tectonics, a divergent boundary is a linear feature that exists between two tectonic plates that are moving away from each other. Evidence that supports the theory of plate tectonics includes distribution of rock formation and fossils, shapes of existing continents, ocean floor features, and seismic and volcanic activity. Plate tectonics article about plate tectonics by the free. For the rest of us, plate tectonics is a simple theory that.
Plate tectonics information and facts national geographic. Depending on the material they travel through, the waves may either speed up, slow down, bend, or even stop if they cannot penetrate the material they encounter. The plate tectonics theory and mantle plume concept thus complement each other to ex. Knowledge of earths interior is derived primarily from analysis of the seismic waves that propagate through earth as a result of earthquakes. For the rest of us, plate tectonics is a simple theory that helps make sense of the earths face. The earths crust is divided into plates which are moved in various directions. The lithosphere lithosphere is comprised of the upper mantle and the crust, the outer shell of the earth. Plate tectonics interactive notebook a compilation of 9 plate tectonics resources including foldables, wordmeaning sort, pages to glue in, and a layers of the earth flip book, that can be used in your students science interactive notebooks. Exactly how this works is still a matter of debate.
The major mountainbuilding idea that was supported from the 19 th century and into the 20 th is the geosynclinal theory. Earths tectonic platesmap showing earths major tectonic plates with arrows depicting the directions of plate movement. Larger faults are mostly from action occuring in earths plates. The plates are constantly moving over this weaker layer. Plate tectonics print materials with information on plate tectonics computer with internet access world map outlines with no placename labels, 1 per student pencils and erasers markers, colored pencils, or crayons procedures 1. In other words, cooling of the mantle leads to plate tectonics while cooling of the core is responsible for mantle plumes. Plate tectonics is the process that drives the recycling of earths oceanic crust and the drift of continents on its surface. Plate tectonics is the surface manifestation of mantle convection, but the large contrast in viscosities between the lithosphere and the deeper mantle. 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. The definition of tectonic plates for kids involves thinking of the earths crust as large slabs that move over a liquid mantle. Tectonic definition is of or relating to tectonics.