The rocky masses which form the two sides of the fault then snap back into a new position. Video lecture by ross stein of the usgs exerpt from the video, shock waves. The elastic rebound theory suggests which of the following. Fault creep stable sliding slip is slow and gradual for extremely smooth fault.
Energy built up when plates try to get past each other is released when plates break free. Similar to its predecessors, ucerf3 is composed of the. Earthquakes occurring along subduction zones cause tsunamis. It will resist that forces till it exceeds its capacity and after that, it snaps. The stored elastic energy has to go somewhere because it has been suddenly released. What type of faults were the two alaska earthquakes 1964 and 2002 discussed in chapter 1. Fixed recurrence and slip models better predict earthquake behavior. For example, a large earthquake on one fault might not only release stress on that fault, but would also change the stress on other segments of that fault or nearby faults. From an examination of the displacement of the ground surface which accompanied the 1906 earthquake, henry fielding reid. Procedure for rebound hammer test on concrete structure starts with calibration of the rebound hammer. An elastic rebound model for normal fault earthquakes wiley. The elastic rebound theory is the first theory that describes.
Elastic rebound theory rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. Review the inclass quizzes and supplemental online quizzes. Elastic rebound theory discovered by analysis of the fault motion and deformation before and during the 1906 san francisco earthquake before plate tectonics theory. Elastic reboundtheory elasticrebound theelasticreboundtheoryisanexplanationforhow energyisspreadduringearthquakes. This snapping back into position, upon the release of strain, is the elastic rebound of reids theory. Longterm timedependent probabilities for the third. In geology, the elasticrebound theory is an explanation for how energy is released during an earthquake. In this study we test the validity of the elastic rebound theory in the quasidynamic fault model of. Earthquake occurs when shear stress exceeds shear strength of the rocks along the fault 3. None of the above are aspects of the elastic rebound theory. Missouri university of science and technology scholars mine.
This gradual accumulation and release of stress and strain is now referred to as the elastic rebound theory of earthquakes. Elastic rebound theory refers to the set of facts surrounding how energy is generated and spreads during an earthquake. Plate tectonics pwaves, swaves, and surface waves elastic rebound and seismic gap theory pwaves are a type of seismic wave that can travel through a continuum of gases as sound waves they are the primary wave. This is the principle that reid proposes through his elastic rebound theory of earthquakes. It is a way for the stored energy to be released through a sudden action. Soil capacity improvement to present the soil capacity improvement according to the elastic rebound theory and during retapping process, figure 3 is shown different soil layers before and after earthquake that it can be used for pile driving. List the key observations that revealed earth to possess a. Definition of elastic rebound theory in the dictionary. Take a rubber band and stretch it as much as you can, give it everything. What does the difference in arrival times of p and s waves at a single seismograph station tell you about an earthquake. For this, the rebound hammer is tested against the test anvil made of steel having brinell hardness number of about 5000 nmm2. A list of lyrics, artists and songs that contain the term elastic rebound theory from the website. The first is usually the elastic deformation state.
Elastic rebound theory jerky motions on faults produce. Stickslip sliding alternating time periods of noslip and suddenslip. Each type of plate intersection produces significant straining in crustal rocks. In geology, the elastic rebound theory was the first theory to satisfactorily explain earthquakes. Theory is consistent with plate tectonics, in fact, it explains how the slow motions of the plates can result in the rapid slip along a fault to produce an earthquake. Earthquakes with a very deep focus cannot be explained by the elastic rebound theory. Describe the characteristics of seismic waves and explain the difference between primary waves, secondary waves, and surface waves.
Reids elastic rebound theory usgs earthquake hazard program. The model presented here therefore represents our best estimate of the elastic rebound component of the system, under the assumption such behavior exists and can be meaningfully isolated from other time dependencies. Elastic rebound theory discovered by analysis of the fault. Elastic rebound theoryelastic rebound theory this theoryyyg was discovered by making measurements at a number of points across a fault. Elastic rebound theory jerky motions on faults produce eqs three fs of earthquakes.
The fault then ruptures that is, it suddenly moves a comparatively large distance comparatively short amount of time. As the earths crust deforms, the rocks which span the opposing sides of a fault are subjected to shear stress. Elastic rebound theory article about elastic rebound theory. Seismic waves may travel either through the earths interior p and s waves. The elastic rebound theory explains how energy is produced when an earthquake occurs. Elastic rebound theory more grades 912 science on the learning videos channel duration. Over time stresses in the earth build up often caused by the slow movements of tectonic plates. Slowly they deform, until their internal rigidity is exceeded. Figure 1 shows the patterns of surface deformation. P and s waves can also be generated in the slinky by an additional method that reinforces the concept of elasticity and the elastic rebound theory which explains the generation of earthquakes by plate tectonic movements bolt, 1993, p. Explain the elastic rebound theory, which provides an explanation for the origin of earthquakes. However some of the characteristics of earthquakes can be explained by using a simple elastic rebound theory.
Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. Reid gave, for example, a crude forecast of the next great earthquake near san francisco. Reid after the 1906 san francisco earthquake, implies that the rupture process at the fault surface is responsible for the relative displacement across the fault and hence the seismic waves radiated during the earthquake. Reids elastic rebound theory from an examination of the displacement of the ground surface which accompanied the 1906 earthquake, 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. The elastic rebound theory is an explanation for how. Stress on a fault slowly accumulates within the rocks 2. Elastic rebound theory says that earthquakes are produced when a. The elastic rebound theory of earthquake sources allows rough prediction of the occurrence of large shallow earthquakes.
This theory states that the failure occurs when the maximum shear strain energy component for the complex state of stress system is equal to that at the yield point in the tensile test. The elastic rebound theory is the first theory that describes fault rupture as the source of strong ground shaking. The force per unit area acting on a rock is called stress. How rocks respond to stress is a fundamental concept, critical to forming explanatory models in the geosciences e. Shallow foci but can have high magnitude due to high strength of continental basement rocks. Jan 12, 2014 the rocky masses which form the two sides of the fault then snap back into a new position. At some point the stresses become so great that the. The british geological survey school seismology support. 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. Slow accumulation and rapid release of elastic energy. As is the case with all materials, there is a limit. This snapping back into position, upon the release of strain, is the elastic rebound of reids theory the elastic rebound theory is an explanation for how energy is spread during earthquakes. This activity was developed for use in a high school grades 912 earth science class. Oct 25, 2010 the deformation of rocks takes place through several stages.
In the theory, fault movements are based on the ability of rock to stick to each other while under stress. Elastic rebound definition of elastic rebound by the free. Reids elastic rebound theory from an examination of the displacement of the ground surface which accompanied the 1906 earthquake, henry fielding reid, professor of geology at johns hopkins university, concluded that the earthquake must have involved an elastic rebound of previously stored elastic. A theory which attributes faulting to stresses in the form of potential energy which are being built up in the earth and which, at discrete intervals, are suddenly released as elastic energy. In the topics below, where did we spend time on annotated sketches. 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. Dec 08, 2015 first a few examples of energy pumped into a system. Theory of elasticity and plasticity full notes ebook free. Similarly, the crust of the earth can gradually store elastic stress that is released suddenly during an earthquake. Ppt elastic rebound theory powerpoint presentation free. Most earthquakes are the result of the sudden elastic rebound of previously stored energy. Tohoku earthquake in japan with the observed radiated seismic energy.
Elastic rebound theory this theory was discovered by making measurements at a number of points across a fault. Rebound hammer test on concrete principle, procedure. When the stress becomes too great then the rocks separate and an earthquake results. The british geological survey school seismology support documents elastic rebound. 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. Practically what this means is, if the rock is deformed below a certain level the brittle failure point or the point of plastic deformation, if the stress is released the rock will return to its original shape with no sign of the deformation.
Elastic rebound theory jerky motions on faults produce eqs. The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9. Elastic rebound definition of elastic rebound by the. In geology, the elasticrebound theory is an explanation for how energy is released during an create a book download as pdf printable version 1. The three types of directional stress experienced by rocks are compressional, tensional, and shear stress fig.
The plates of the earth are in constant motion, and plate tectonics indicates that the majority of their relative movement most damaging earthquakes form on faults at depth of five miles or more in the. Harry fielding reid, american seismologist and glaciologist who in 1911 developed the elastic rebound theory of earthquake mechanics, still accepted today. Prior to an earthquake it was noted that the rocks adjacent to the fault were bending theserocks adjacent to the fault were bending. Elastic rebound theory 11 faults get locked when friction faults get locked when friction between plates prevents movement. The elastic rebound theory was first stated in volume i, part i. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Reid was professor of applied mechanics at johns hopkins university, baltimore, from 1896 until he became emeritus professor in 1930. Review questons chapter 6 and 7 flashcards quizlet. San andreas fault figure 1 the nature of earthquakes. Whereas learners are likely to have lots of experience with rocks, few will have directly experienced them behaving elastically. Earthquakes 7 tectonic settings of earthquakes intraplate bowling green most often associated with failed rift zones and reactivation of ancient faults. Earthquakes earthquake measurements slides and pdf files. What makes an elastic rebound possible during an earthquake. Theory of elasticity and plasticity full notes ebook free download pdf there are various elastic moduli, such as youngs modulus, the shear modulus, and the bulk modulus, all of which are measures of the inherent stiffness of a material as a resistance to deformation under an applied load.
Earthquakes occur along faults, or rupturesfractures in the lithosphere where. None of the above are aspects of the elastic rebound. Geology 15 fall 20 lecture 2 alaska pop extensional c. At some point the stresses become so great that the earth breaks. 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. It may be noted that this theory gives fair by good results for ductile materials. Elasticrebound theory article about elasticrebound theory. Harry fielding reid american seismologist britannica. Our new crystalgraphics chart and diagram slides for powerpoint is a collection of over impressively designed datadriven chart and editable diagram s guaranteed to impress any audience.
Previously it was thought that ruptures of the surface were the result of strong ground shaking. It is a bit broader than our previous subduction zone example, but often. Which of the following is an aspect of the elastic rebound theory. Life after death experience nde with steve gardipee, vietnam war story one of the best ndes duration. The mechanisms and processes involved when earthquakes occur are extremely complex.
According to the theory, a tectonic earthquake occurs when strains in rock masses have accumulated to a point where the. The theory also predicted, of course, that the place would be along read more. Reids elastic rebound theory usgs earthquake hazards. In geology, the elasticrebound theory is an explanation for how energy is released during an. Melinda hutson 2 april 2010 elastic rebound theory the theory was first proposed in 1906 by h. 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. In geology, the elastic rebound theory is a theory which tries to explain why earthquakes occur. Swaves are a type of elastic body wave that moves through the. If a seismograph station measures p waves but no s waves from an earthquake what can you conclude about the earthquakes location. In geology, the elastic rebound theory is an explanation for how energy is released during an earthquake. Theory of elastic stability by timoshenko, stephen, 18781972. According to this theory as adjoining plates on the earths surface move in opposite directions, then the rocks which span the opposing sides of the incipient fault are subjected to extreme shear stress. The strain is accumulated by gradual shifting of tectonic plates. Rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation.
What links here related changes upload file special pages permanent link page. In geology, the elastic rebound theory was the first theory. Intro to earthquakes pennsylvania state university. Elastic energy is released earthquake through suddenslip.
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