Prior to an earthquake it was noted that the rocks adjacent to the fault were bending. Since fault planes are not usually very smooth, great amounts of energy can be stored if the rock is strong enough as movement is restricted due to interlock along the fault. Elastic rebound theory moment magnitude scale earthquakes. It was the last half of the 19 th century in the united states. The elastic rebound theory of earthquake sources allows rough prediction of the occurrence of large shallow earthquakes. Elastic rebound definition at, a free online dictionary with pronunciation, synonyms and translation. Multiple choice questions for earthquakes chapter 16. Normal fault vertical motion due to tensional stress. Ppt elastic rebound theory powerpoint presentation. Have students line up face to face with their hands in front of them, palm to palm. Elastic rebound demonstration using a yardstick video lecture about elastic rebound and brittle material in the crust using a yardstick as a mechanical analog. 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. Pdf on incorrectness in elastic rebound theory for cause of. In geology, the elastic rebound theory was the first theory to satisfactorily explain earthquakes.
This gradual accumulation and release of stress and strain is now referred to as the elastic rebound theory of earthquakes. The earthquakes are usu ally associated with the known types of faults depicted in fig. The mechanisms and processes involved when earthquakes occur are extremely complex. 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 is directly related to earthquakes.
A list of lyrics, artists and songs that contain the term elastic rebound theory from the website. The elastic rebound theory was suggested by henry feilding reid, who made observations and summarized that the earthquake occurs as a consequence of an elastic rebound of elastic strain energy that was previously stored in the rocks on either side of the fault. The theory also predicted, of course, that the place would be along tectonic earthquakes. According to the theory, a tectonic earthquake occurs when strains in rock masses have accumulated to a point where the. Subsequently, the elastic rebound theory for the cause of earthquake was developed, established and used by many others. It is only partially correct because it associates earthquakes with geological faults. The elastic rebound theory has been summa rized by berlin 1980. A body with this ability is said to behave or respond elastically. Passing right down the middle of the orchard, and across the road, is a fault zone. Slowly they deform, until their internal rigidity is exceeded. Elasticity, ability of a deformed material body to return to its original shape and size when the forces causing the deformation are removed.
As rocks on oppo site sides of a fault are subjected to force and shift. The elastic rebound theory suggests which of the following. Elastic rebound theory this theory was discovered by making measurements at a number of points across a fault. Ppt elastic rebound theory powerpoint presentation free. The first is the interseismic stage, during which elastic strain accumulates slowly with time due to the relative motion of the adjacent plates. The rocky masses which form the two sides of the fault then snap back into a new position. The elastic rebound theory was first stated in volume i, part i. Brief description correspondingly, the existing elastic rebound theory in. From fragmentary ground dis placement data, reid proposed the elastic rebound theory to account for strike slip displacements at the time of. 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. From an examination of the displacement of the ground surface which accompanied the 1906 earthquake, henry fielding reid. 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.
In geology, the elasticrebound theory is an explanation for how energy is released during an earthquake. Mar 26, 2011 elastic rebound theory more grades 912 science on the learning videos channel duration. It has been the main stream theory for the past one hundred years. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Reid of johns hopkins university, who served on lawsons commission. Elastic rebound theoryelastic rebound theory this theoryyyg was discovered by making measurements at a number of points across a fault. 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 theory states that as tectonic plates move relative to each other, elastic strain energy builds up along their edges in the rocks along fault planes. Reids elastic rebound theory usgs earthquake hazards. In geology, the elasticrebound theory is an explanation for how energy is released during an.
The elastic rebound theory is an explanation for how energy is spread during earthquakes. The time sequence of the theory is illustrated in fig. The three types of directional stress experienced by rocks are compressional, tensional, and shear stress fig. In his hitchcock lectures at the university of california in 1911, reid presented the theory in a clear and general form. An elastic rebound model for normal fault earthquakes wiley. Elasticreboundtheory elasticrebound theelasticreboundtheoryisanexplanationforhow energyisspreadduringearthquakes.
In his hitchcock lectures at the university of california in 1911. The role of the elastic rebound theory in design and. However, it is inconsistent and even violates many other phenomena that were present before, during and after earthquakes. Assuming that the dislocation front propagates in one direction along the long. This theory is known as the elastic rebound theory. Over time stresses in the earth build up often caused by the slow movements of tectonic plates. Elastic rebound theory rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. At some point the stresses become so great that the. This is something like pulling a rubber band gradually until the band snaps. Elastic rebound theory refers to the set of facts surrounding how energy is generated and spreads during an earthquake. In this study we test the validity of the elastic rebound theory in the quasidynamic fault model of. Elastic rebound theory tells us that the elastic strain energy, when not released immediately through creep or other anelastic processes, accumulates over time and this stored energy is available to be. Elastic rebound theory more grades 912 science on the learning videos channel duration. The seismic cycle and the difference between foreshocks and aftershocks.
Most earthquakes are the result of the sudden elastic rebound of previously stored energy. This demonstrates elasticity, brittle fracture, and why it is difficult to predict earthquakes. Dec 02, 2017 elastic rebound theory meaning elastic rebo. Elastic rebound theory 1 no transcript 2 no transcript 3 no transcript 4 no transcript 5 no transcript 6 elastic rebound theory 7 no transcript 8 no transcript 9 earthquake phenomenon 10 no transcript 11 no transcript 12 no transcript energy magnitude relationship energy release increases by 32 times with increase. These observations provided the basis for the landmark theory of elastic rebound, introduced by professor h. The elasticrebound theory explains how energy is produced when an earthquake occurs. When reid 1910 proposed his elastic rebound theory of. Elastic reboundtheory elasticrebound theelasticreboundtheoryisanexplanationforhow energyisspreadduringearthquakes. Pdf the seismic cycle and the difference between foreshocks. A joint boundary consisting of 30 joint elements was used to simulate the slip surface. For this purpose, a hypothetical planar footwall slab was modeled with different excavation stages and pit depths. The elastic rebound theory was developed 100 years ago from the observations of coseismic surface ruptures induced by the 1906 california earthquake.
Similarly, the crust of the earth can gradually store elastic stress that is released suddenly during an earthquake. How a big disaster helped us better understand how the earth works. The following animation shows a birds eye view of a country road that cuts through an orchard. Geological survey, who also served on the lawson commission. However some of the characteristics of earthquakes can be explained by using a simple elastic rebound theory.
The force per unit area acting on a rock is called stress. The gradual accumulation and release of stress and strain is called the elastic rebound theory of earthquakes. Elastic rebound definition of elastic rebound by the free. Numerical modeling of shear stress and displacement reversals. Elasticrebound theory article about elasticrebound theory. It is a bit broader than our previous subduction zone example, but often. Elastic rebound in geology, the elastic rebound theory is an explanation for how energy is released during an earthquake. Previously it was thought that ruptures of the surface were the. The elastic rebound theory explains how energy is produced when an earthquake occurs. Numerical modeling of shear stress and displacement. Elastic rebound theory article about elastic rebound theory. Basically elastic rebound is the primary reason earthquakes even happen. Reids theory extended earlier insights into the earthquake process by g.
As the earths crust deforms, the rocks which span the opposing sides of a fault are subjected to shear stress. 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. According to the elastic rebound theory reid, 1910, the seismic cycle consists of two phases. On incorrectness in elastic rebound theory for cause of. The first is the interseismic stage, during which elastic strain accumulates slowly with time due to.
To a greater or lesser extent, most solid materials exhibit elastic behaviour, but there. 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. Fixed recurrence and slip models better predict earthquake. Previously it was thought that ruptures of the surface were the result of strong ground shaking. Prior to an earthquake it was noted that the rocks adjacent to the fault were bending theserocks adjacent to the fault were bending. How is the elastic rebound theory related to earthquakes.
Fixed recurrence and slip models better predict earthquake behavior. Due to the motion of the earths tectonic plates, the ground beneath our feet is always moving, just too slow and g. Elastic rebound theory tells us that the elastic strain energy, when not released immediately through creep or other anelastic processes. Reid, 1910 has been used to describe the behavior of faults and fault systems.
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