Harry fielding reid, american seismologist and glaciologist who in 1911 developed the elastic rebound theory of earthquake mechanics, still accepted today. It will resist that forces till it exceeds its capacity and after that, it snaps. 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. This snapping back into position, upon the release of strain, is the elastic rebound of reids theory.
Review questons chapter 6 and 7 flashcards quizlet. Longterm timedependent probabilities for the third. Elastic energy is released earthquake through suddenslip. What does the difference in arrival times of p and s waves at a single seismograph station tell you about an earthquake. Elastic rebound theory says that earthquakes are produced when a. Jan 12, 2014 the rocky masses which form the two sides of the fault then snap back into a new position. An elastic rebound model for normal fault earthquakes wiley. Earthquakes 7 tectonic settings of earthquakes intraplate bowling green most often associated with failed rift zones and reactivation of ancient faults. Earthquake occurs when shear stress exceeds shear strength of the rocks along the fault 3. Melinda hutson 2 april 2010 elastic rebound theory the theory was first proposed in 1906 by h. From an examination of the displacement of the ground surface which accompanied the 1906 earthquake, henry fielding reid. Rebound hammer test on concrete principle, procedure. The british geological survey school seismology support documents elastic rebound.
The british geological survey school seismology support. Stress on a fault slowly accumulates within the rocks 2. Rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. 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. At some point the stresses become so great that the. What type of faults were the two alaska earthquakes 1964 and 2002 discussed in chapter 1. San andreas fault figure 1 the nature of earthquakes. Earthquakes earthquake measurements slides and pdf files. Stickslip sliding alternating time periods of noslip and suddenslip. The elastic rebound theory was first stated in volume i, part i. Energy built up when plates try to get past each other is released when plates break free. Whereas learners are likely to have lots of experience with rocks, few will have directly experienced them behaving elastically. 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 theory also predicted, of course, that the place would be along read more. 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. Oct 25, 2010 the deformation of rocks takes place through several stages. The stored elastic energy has to go somewhere because it has been suddenly released. Prior to an earthquake it was noted that the rocks adjacent to the fault were bending theserocks adjacent to the fault were bending. 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. 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.
Swaves are a type of elastic body wave that moves through the. 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. Information and translations of elastic rebound theory in the most comprehensive dictionary definitions resource on the web. The rocky masses which form the two sides of the fault then snap back into a new position. According to the theory, a tectonic earthquake occurs when strains in rock masses have accumulated to a point where the. Elastic rebound theory more grades 912 science on the learning videos channel duration. Harry fielding reid american seismologist britannica. This activity was developed for use in a high school grades 912 earth science class.
The elastic rebound theory of earthquake sources allows rough prediction of the occurrence of large shallow earthquakes. It may be noted that this theory gives fair by good results for ductile materials. In geology, the elasticrebound theory is an explanation for how energy is released during an. Elastic rebound theory rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. Elastic rebound definition of elastic rebound by the. In geology, the elasticrebound theory is an explanation for how energy is released during an earthquake. It is a bit broader than our previous subduction zone example, but often. What makes an elastic rebound possible during an earthquake. 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. Elastic rebound theory jerky motions on faults produce eqs three fs of earthquakes. The elastic rebound theory is the first theory that describes fault rupture as the source of strong ground shaking.
In this study we test the validity of the elastic rebound theory in the quasidynamic fault model of. This gradual accumulation and release of stress and strain is now referred to as the elastic rebound theory of earthquakes. Life after death experience nde with steve gardipee, vietnam war story one of the best ndes duration. Figure 1 shows the patterns of surface deformation. Earthquakes occur along faults, or rupturesfractures in the lithosphere where. Fault creep stable sliding slip is slow and gradual for extremely smooth fault. In geology, the elastic rebound theory is an explanation for how energy is released during an earthquake. 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. Theory of elasticity and plasticity full notes ebook free. The three types of directional stress experienced by rocks are compressional, tensional, and shear stress fig. 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.
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. The fault then ruptures that is, it suddenly moves a comparatively large distance comparatively short amount of time. At some point the stresses become so great that the earth breaks. Reid gave, for example, a crude forecast of the next great earthquake near san francisco.
Tohoku earthquake in japan with the observed radiated seismic energy. 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. Fault zones are often located near major population centers. Similarly, the crust of the earth can gradually store elastic stress that is released suddenly during an earthquake. Dec 08, 2015 first a few examples of energy pumped into a system. Elastic reboundtheory elasticrebound theelasticreboundtheoryisanexplanationforhow energyisspreadduringearthquakes.
Slowly they deform, until their internal rigidity is exceeded. Elastic rebound theory jerky motions on faults produce. Elastic rebound theory 11 faults get locked when friction faults get locked when friction between plates prevents movement. Slow accumulation and rapid release of elastic energy. Geology 15 fall 20 lecture 2 alaska pop extensional c. Learn vocabulary, terms, and more with flashcards, games, and other study tools. The elastic rebound theory suggests which of the following. 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. Ppt elastic rebound theory powerpoint presentation free. In the topics below, where did we spend time on annotated sketches. The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9.
Most earthquakes are the result of the sudden elastic rebound of previously stored energy. Each type of plate intersection produces significant straining in crustal rocks. 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. Elastic rebound definition of elastic rebound by the free. Previously it was thought that ruptures of the surface were the result of strong ground shaking. The elastic rebound theory is the first theory that describes. Shallow foci but can have high magnitude due to high strength of continental basement rocks. Theory of elastic stability by timoshenko, stephen, 18781972. Missouri university of science and technology scholars mine. Video lecture by ross stein of the usgs exerpt from the video, shock waves.
Definition of elastic rebound theory in the dictionary. Elastic rebound theory article about elastic rebound theory. How rocks respond to stress is a fundamental concept, critical to forming explanatory models in the geosciences e. None of the above are aspects of the elastic rebound theory.
As the earths crust deforms, the rocks which span the opposing sides of a fault are subjected to shear stress. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. Intro to earthquakes pennsylvania state university. None of the above are aspects of the elastic rebound. Which of the following is an aspect of the elastic rebound theory. Reids elastic rebound theory usgs earthquake hazard program. It is a way for the stored energy to be released through a sudden action. The first is usually the elastic deformation state. A physical basis for earthquakes based on the elastic rebound model. 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.
Explain the elastic rebound theory, which provides an explanation for the origin of earthquakes. 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. 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. If a seismograph station measures p waves but no s waves from an earthquake what can you conclude about the earthquakes location. Reid was professor of applied mechanics at johns hopkins university, baltimore, from 1896 until he became emeritus professor in 1930. 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 an explanation for how.
Elastic rebound theory refers to the set of facts surrounding how energy is generated and spreads during an earthquake. The force per unit area acting on a rock is called stress. Seismic waves may travel either through the earths interior p and s waves. In geology, the elastic rebound theory was the first theory. Over time stresses in the earth build up often caused by the slow movements of tectonic plates. Before this principle the fault rupture was believed to be the result of earth shaking. The mechanisms and processes involved when earthquakes occur are extremely complex.
For this, the rebound hammer is tested against the test anvil made of steel having brinell hardness number of about 5000 nmm2. In the theory, fault movements are based on the ability of rock to stick to each other while under stress. In geology, the elastic rebound theory is a theory which tries to explain why earthquakes occur. Procedure for rebound hammer test on concrete structure starts with calibration of the rebound hammer. Describe the characteristics of seismic waves and explain the difference between primary waves, secondary waves, and surface waves. Earthquakes with a very deep focus cannot be explained by the 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. The strain is accumulated by gradual shifting of tectonic plates. Elastic rebound theory discovered by analysis of the fault motion and deformation before and during the 1906 san francisco earthquake before plate tectonics theory. The rocks become disturbed but maintain their original positions because of continuity, mechanical bond and friction. Earthquakes occurring along subduction zones cause tsunamis. Review the inclass quizzes and supplemental online quizzes.
A list of lyrics, artists and songs that contain the term elastic rebound theory from the website. Elastic rebound theory jerky motions on faults produce eqs. This is the principle that reid proposes through his elastic rebound theory of earthquakes. The elastic rebound theory explains how energy is produced when an earthquake occurs. Elasticrebound theory article about elasticrebound theory. 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. As discussed in chapter 3, when brittle rocks are subjected to stress, the rocks undergo elastic deformation during which they store the energy of the stress see figure 4. As is the case with all materials, there is a limit. Similar to its predecessors, ucerf3 is composed of the. Elastic rebound theory discovered by analysis of the fault. 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. 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 was the first theory to satisfactorily explain earthquakes.
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