D all of the above elastic rebound theory suggests. Learning earthquake tip 1 earthquake design and construction. Whereas learners are likely to have lots of experience with rocks, few will have directly experienced them behaving elastically. The material for the next two lectures is based on chapter 8. How do earth scientists explain this contradiction. Slowly they deform, until their internal rigidity is exceeded. List the key observations that revealed earth to possess a. Earthquakes 7 tectonic settings of earthquakes intraplate bowling green most often associated with failed rift zones and reactivation of ancient faults. After the devastating 1906 san francisco, california earthquake, a fault trace was discovered that could be followed along the ground in a more or less straight line for 270 miles. Pdf physical mechanism of major earthquakes by earthquake cases.
Causes of earthquakes earthquake hazard and emergency management 27 c. Fault zones are often located near major population centers. Elastic rebound theory this theory was discovered by making measurements at a number of points across a fault. This activity was developed for use in a high school grades 912 earth science class. Fixed recurrence and slip models better predict earthquake. In geology, the elastic rebound theory is an explanation for how energy is released during an earthquake. Earthquakes affect almost every part of the earth and like rain they can be either mild or catastrophic. Stickslip sliding alternating time periods of noslip and suddenslip. As the earths crust deforms, the rocks which span the.
Life after death experience nde with steve gardipee, vietnam war story one of the best ndes duration. Elastic strain buildup and brittle rupture stage b figure 7. The theory involves the slow build up of elastic strain due to largescale stresses in the crust on either side of a locked fault i. In elastic rebound theory, what must occur to produce an earthquake. Elastic rebound theory rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. Learn vocabulary, terms, and more with flashcards, games, and other study tools. The mechanisms and processes involved when earthquakes occur are extremely complex. Which of the following is an aspect of the elastic rebound theory. Elastic rebound theory eventually, the strain along the fault exceeds the limit of the rocks at that point to store any additional strain.
A better understanding of these processes provides an improved ability to anticipate and communicate the unique aspects of earthquake hazards. Photos, videos, and podcasts selected lists of earthquake damage, faults, and effects photos, videos, and podcasts. Reids elastic rebound theory rocks store elastic energy until they cannot store it any longer, then snap like a rubberband. According to the theory, a tectonic earthquake occurs when strains in rock masses have accumulated to a point where the. The gradual accumulation and release of stress and strain is called the elastic rebound theory of earthquakes. Slow accumulation and rapid release of elastic energy. The elastic rebound theory is an explanation for how energy is spread during earthquakes. The stored elastic energy has to go somewhere because it has been suddenly released. Tectonics are explained by the socalled elastic rebound theory, formulated by the american geologist harry fielding reid after the san andreas fault ruptured in 1906, generating the great san francisco earthquake. The force per unit area acting on a rock is called stress.
Presently, no models of normal fault earthquake cycles exist, and in. Reids elastic rebound theory usgs earthquake hazards. How is the elastic rebound theory related to earthquakes. Jul 03, 2018 earthquakes earthquake measurements slides and pdf files 1.
Earthquakes occurring along subduction zones cause tsunamis. The material for the next two lectures is based on chapter 8 pgs 2516 press and siever 1994. What happens when the narcissist knows youve figured them out duration. Observation and interpretation of precursory phenomena. It can be done in small groups or as a classroom demonstration, with students recording data. Basically elastic rebound is the primary reason earthquakes even happen. His theory of how earthquakes occur as a result of fracture of rocks along a fault is called elastic rebound theory. According to elastic rebound theory, the blocks of rock on opposite side of a fault are forced in opposite directions by stress. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. On earths surface, any straight line like a road or a fence a crossing a fault would be gradually deformed or bent b as rocks on one side of the fault move relative to those on the other side. Over time stresses in the earth build up often caused by the slow movements of. Mar 09, 2016 this video discusses the relationship between plate boundaries and earthquakes, deformation, elastic limit and rebound and the 3 kinds of faults earthquakes can happen in.
This gradual accumulation and release of stress and strain is now referred to as the elastic rebound theory of earthquakes. This activity helps learners see the elastic properties of rocks by actually bending marble. Dependent friction spatial heterogeneity stress corrosion slider. Earthquakes can be so small they go completely unnoticed, or so large that it can take years for a region to recover. On the other hand, the plate tectonic theory gives the reasons why and how the elastic stress can be built up in crustal fault rocks for cause of earthquakes associated with the elastic rebound theory 5. Nov 17, 20 the elastic rebound theory predicts that earthquakes can be generated only in the lithosphere. Reid, university of california publications, bulletin of the department of geology, 6, 19, 1911.
Causes of earthquakes earthquake hazard and emergency management 22 nature of the causative geological processes is of particular relevance. Earthquakes are caused by plate interactions along tectonic plate. The sudden release of energy should cause the youth to stumble and possibly tumble. Energy built up when plates try to get past each other is released when plates break free. Over time stresses in the earth build up often caused by the slow movements of tectonic plates. The elastic rebound theory predicts that earthquakes can be generated only in the lithosphere.
When the strength of the rock is exceeded, it suddenly breaks, releasing some of its stored energy as seismic waves. Elastic rebound theory more grades 912 science on the learning videos channel duration. A theory of tectonics in which the outer part of the earth lithosphere is comprised of rigid plates that interact collide, translate, rift apart, subduct. Jan 21, 2016 elastic rebound theory is one of the central ideas to the mechanics of earthquakes and was originally proposed by reid 1910 following the 1906 san francisco earthquake on the san andreas fault. However some of the characteristics of earthquakes can be explained by using a simple elastic rebound theory. Elastic rebound theory of earthquakes in the past, earthquakes were believed to occur because the ground would shake in a very strong manner.
Plate movement concentrates energy in crust when the stored energy exceeds the strength of the crust, the crust ruptures the rupture generally occurs along faults because this is the weakest point. According to the elastic rebound hypothesis, most earthquakes are produced by the rapid release of energy stored in rock that has been subjected to great forces. In geology, the elasticrebound theory is an explanation for how energy is released during an earthquake. What makes an elastic rebound possible during an earthquake. In elastic rebound theory, what must occur to produce an. On incorrectness in elastic rebound theory for cause of. Passing right down the middle of the orchard, and across the road, is a fault zone. However, based on studies done in the tonga islands, earthquakes occur within the weak, ductile asthenosphere.
Over the course of geological time, earthquakes, floods, and other natural events have helped to shape the surface of our planet. Earthquakes and earths interior summary abrupt movements of faults that release elastically stored energy cause earthquakes elastic rebound. Duponts plasticslip theory rocks store bending energy until they cannot store it any longer, then snap like a rubber ball. The location on the earths surface directly above the focus. The collection of material points at the fault over which slip occurs usually constitutes an oblong threedimensional volume, with its long dimension often running into tens of kilometers in case of significant earthquakes. Elastic rebound and friction lab lesson plan by deborah kane and dave van dusen. The theory also predicted, of course, that the place would be along tectonic earthquakes.
Reids elastic rebound theory usgs earthquake hazard program. The fault then rupturesthat is, it suddenly moves a comparatively large distance in a comparatively short amount of time. The elastic rebound theory of earthquake sources allows rough prediction of the occurrence of large shallow earthquakes. Elastic rebound theory time years strength energy elastic stress buildup energy release cumulative slip c a slip a b c a b c time years the earthquake rocks are made of elastic material, and so elastic. Earthquake summary posters for significant earthquakes. None of the above are aspects of the elastic rebound. Shallow foci but can have high magnitude due to high strength of continental basement rocks. Dows recovery theory rocks recover violently when a mass collides with them. Previously it was thought that ruptures of the surface were the result of strong ground shaking. Earthquakes earthquake measurements slides and pdf files. This scenario can happen repeatedly on a 100500 year cycle. Types of earthquakes and faults most earthquakes in the world occur along the.
Ancient cultural explanations of earthquakes were often. Most earthquakes are the result of the sudden elastic rebound of previously stored energy. Which one of the following best characterizes tsunamis a they cause the land to ivy tech community college of indiana scin 100 spring 2014 chapter 10 earth science. Rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. Video lecture by ross stein of the usgs exerpt from the video, shock waves. The term refers to how the earth is built of plates, and the theory. As with the statistical models described previously, these models are based upon the elastic rebound theory of reid 1910, which states that stress builds on a fault during the interseismic period, is released in an earthquake and then reaccumulates in the succeeding interseismic.
Elastic rebound theory jerky motions on faults produce. Jan 12, 2014 elastic rebound theory elastic rebound theory over the course of time, one can observe that the two sides of an active fault are in slow but continuous movement relative to one another. Elastic rebound theory is directly related to earthquakes. The three types of directional stress experienced by rocks are compressional, tensional, and shear stress fig. Reid gave, for example, a crude forecast of the next great earthquake near san francisco. This theory is known as the elastic rebound theory. Plate movement concentrates energy in crust when the stored energy exceeds the strength of the crust, the crust ruptures the rupture generally occurs along faults because this is the weakest point the sudden return of elastically deformed rock to its original shape. Ask students if this feels more like how an earthquake would happen. The masses of rock undergo elastic strain, slowly flexing and moving in opposite directions. Oblique view of a highly generalized animation of a subduction zone where an oceanic plate is subducting beneath a continental plate.
However, based on studies in the tonga islands, earthquakes occur within the weak, ductile asthenosphere. Defining an earthquake defining an earthquake an earthquake is a natural occurrence, like rain. In geology, the elastic rebound theory was the first theory to satisfactorily explain earthquakes. Energy released at an earthquakes focus radiates outward as body waves, which are of two kinds. This simulates the build up and stress release of an earthquake, known as elastic rebound theory. It is a way for the stored energy to be released through a sudden action. Elastic rebound theory is one of the central ideas to the mechanics of earthquakes and was originally proposed by reid 1910 following the 1906 san francisco earthquake on the san andreas fault. Elastic rebound theory involves the sudden release of progressively stored strain in rocks, causing movement along a fault. In 1906, henry fielding reid, professor of geology at johns hopkins university, concluded that the earthquake must have involved an elastic rebound of previously stored elastic stress.
This is the principle that reid proposes through his elastic rebound theory of earthquakes. Introduction earthquake sequences elastic rebound theory rate. The goal of this lesson is for students to learn the concepts of elastic rebound and friction and how these apply to earthquakes and faults. Elastic rebound theory this explains how energy is released during earthquakes. As the earths crust deforms, the rocks which span the opposing sides of a fault are subjected to shear stress. Describe the characteristics of seismic waves and explain the difference between primary waves, secondary waves, and surface waves. The elasticrebound theory of earthquakes bulletin of. At some point the stresses become so great that the. Elastic rebound theory time years strength energy elastic stress buildup energy release cumulative slip a c slip a b c a b c time years the earthquake rocks are made of elastic material, and so elastic. Feb 22, 2014 1 the veolcity of s waves decreases as the waves enter the asthenosphere what does this suggest about the asthenosphere compared to the overlying lithosphere.
Earthquake vibrations are measured with seismometers. Type of faults dip slip faults strike slip faults figure 6. Previously it was thought that ruptures of the surface were the result of strong ground shaking rather than the converse suggested by this theory. This lab exercise teaches students about elastic rebound and friction and how these concepts related to earthquakes. The following animation shows a birds eye view of a country road that cuts through an orchard.
The material for the next two lectures is based on chapter. Explain the elastic rebound theory, which provides an explanation for the origin of earthquakes. Illuminates the causes of earthquakes by elastic rebound theory and earthquake location as focus and epicenter. An elastic rebound model for normal fault earthquakes wiley. How rocks respond to stress is a fundamental concept, critical to forming explanatory models in the geosciences e. Similarly, the crust of the earth can gradually store elastic stress that is released suddenly during an earthquake. A range of mechanisms has been proposed for earthquakes, including elastic rebound hypothesis reid. However, based on studies in the tonga islands, earthquakes occur within the weak, ductile. Elastic reboundtheory elasticrebound theelasticreboundtheoryisanexplanationforhow energyisspreadduringearthquakes.
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