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. Slowly they deform, until their internal rigidity is exceeded. The theory also predicted, of course, that the place would be along read more. Which of the following is not explained by the elastic rebound theory. Over time stresses in the earth build up often caused by the slow movements of tectonic plates. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. This gradual accumulation and release of stress and strain is now referred to as the elastic rebound theory of earthquakes. Due to the motion of the earths tectonic plates, the ground beneath our feet is always moving, just too slow and g. What is the elastic rebound theory and how does it relate to.
In elastic rebound theory, what must occur to produce an earthquake. According to the elastic rebound hypothesis most earthquakes. The elastic rebound theory is an explanation for how energy is spread during earthquakes. This process of strain, stress, and failure is referred to as the elasticrebound theory. The elastic rebound theory is explained, as well as the different types of waves and how they are measured. On incorrectness in elastic rebound theory for cause of. However some of the characteristics of earthquakes can be explained by using a simple elastic rebound theory.
Basically elastic rebound is the primary reason earthquakes even happen. Nov, 2008 video lecture by ross stein of the usgs exerpt from the video, shock waves. Pdf on incorrectness in elastic rebound theory for cause of. The force per unit area acting on a rock is called stress. How is the elastic rebound theory related to earthquakes. This is why an earthquake s size is relative to the fault size. Ppt elastic rebound theory powerpoint presentation free. The elastic rebound theory was developed 100 years ago from the observations of coseismic surface ruptures induced by the 1906 california earthquake. It is estimated that only 10 percent or less of an earthquake s total energy is radiated as seismic energy.
Subsequently, the elastic rebound theory for the cause of earthquake was. Reid gave, for example, a crude forecast of the next great earthquake near san francisco. The base of the model is free to displace in a horizontal direc tion but not in a. This classroom activity would be useful for helping elementary, secondary, middle school, and university students understand this concept. 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. However, based on studies in the tonga islands, earthquakes occur within the weak, ductile. 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. The three types of directional stress experienced by rocks are compressional, tensional, and shear stress fig.
Ppt elastic rebound theory powerpoint presentation. Reid, who anal ysed geodetic surveys between 1851 and 1906 along the san andreas fault, as a comprehensive description of the earthquake mechanism and deformation in time along an active fault proved to be an effective addition to the free. Eventually, the strain is too much and the rest of the plate has moved too far and the fault releases the strain buildup all at once in a big stress release called an earthquake. 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. In his hitchcock lectures at the university of california in 1911. Previously it was thought that ruptures of the surface were the elastic rebound theory. What makes an elastic rebound possible during an earthquake. However, it is inconsistent and even violates many other phenomena that were present before, during and after earthquakes. In elastic rebound theory, what must occur to produce an. A collection of javascript utilities to be incorporated into scientific courseware.
While the elastic rebound theory predicts that large earthquakes occur. An elastic rebound model for normal fault earthquakes wiley. The stored elastic energy has to go somewhere because it has been suddenly released. Elastic rebound theory rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. It is only partially correct because it associates earthquakes with geological faults. This theory is known as the elastic rebound theory. 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. The elastic rebound theory predicts that earth quakes can be generated only in the lithosphere the layer of solid, rigid material. Most earthquakes are the result of the sudden elastic rebound of previously stored energy. Elasticreboundtheory elasticrebound theelasticreboundtheoryisanexplanationforhow energyisspreadduringearthquakes.
As rocks on oppo site sides of a fault are subjected to force and shift. Interestingly, these results are not in agreement with the classical view of the elastic rebound theory reid, 2. At some point the stresses become so great that the. A elastic rebound theory b slip on a fault with a uniform stress drop c seismic moment d energy release during an earthquake ii elastic rebound theory h. How does the elastic rebound theory, taken together with plate tectonics, predict recurring earthquakes at a plate boundary. In the theory, fault movements are based on the ability of rock to stick to each other while under stress. It is a way for the stored energy to be released through a sudden action. Faults occur in rocks of all ages and of all types. The elastic rebound theory was first stated in volume i, part i. The role of the elastic rebound theory in design and. When the strength of the rock is exceeded, it suddenly breaks, releasing some of its stored energy as seismic waves.
This process of gradual buildup of strain and stress punctuated by occasional sudden earthquake failure is referred to as the elasticrebound theory. Multiple choice questions for earthquakes chapter 16 each chapter will include a few questions designed to test your knowledge of material covered in the chapter and in the internetbased resources. Start off with facts about why quakes happen, the elastic rebound theory, the three kinds of seismic waves, and the role played by plate tectonics in causing big shakes. Rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. The mechanisms and processes involved when earthquakes occur are extremely complex. You will also understand the theory of elastic rebound, and how. Reids elastic rebound theory not only allowed to explain the. Theyll learn all about the richter scale and visit parkfield, california a town dedicated to experiments that.
Reid see box below to explain how energy is released during earthquakes. Elastic rebound theory the elastic rebound theory of shallow tectonic earthquakes proposed by h. Oblique view of a highly generalized animation of a subduction zone where an oceanic plate is subducting beneath a continental plate. In this video lesson you will learn what causes earthquakes and where they occur. This is called the elastic rebound theory, and it explains most but not all movements. Similarly, the crust of the earth can gradually store elastic stress that is released suddenly during an earthquake. Request pdf on incorrectness in elastic rebound theory for cause of earthquakes the elastic rebound theory was developed 100 years ago from the observations of coseismic surface ruptures. 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. 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. The elastic rebound theory of earthquake sources allows rough prediction of the occurrence of large shallow earthquakes. The above text is excerpted from the wikipedia article elasticrebound theory of earthquakes, which has been released under the gnu free. Previously it was thought that ruptures of the surface were the result of strong ground shaking.
Nov 28, 2006 eventually, the strain is too much and the rest of the plate has moved too far and the fault releases the strain buildup all at once in a big stress release called an earthquake. Where does rock behave as an elasticbrittle material. Elastic rebound theory is directly related to earthquakes. When the stress becomes too great then the rocks separate and an earthquake results.
Most of the motion along faults can be explained by the plate tectonics theory. While the elastic rebound theory predicts that large earthquakes occur at the. In geology, the elastic rebound theory was the first theory to satisfactorily explain earthquakes. Multiple choice questions for earthquakes chapter 16. In geology, the elastic rebound theory is a theory which tries to explain why earthquakes occur. Evaluate the knowledge you have gained about the causes of earthquakes with this quiz and worksheet. 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. The seismic gap hypothesis holds that most longterm geo. The elastic rebound theory predicts that earth quakes can be.
This scenario can happen repeatedly on a 100500 year cycle. As the earths crust deforms, the rocks which span the opposing sides of a fault are subjected to shear stress. The gradual accumulation and release of stress and strain is called the elastic rebound theory of earthquakes. When the in geology, the elastic rebound theory was the first theory to satisfactorily explain earthquakes. Earthquakes can be caused by faults, the motion of magma, and explosions e. Passing right down the middle of the orchard, and across the road, is a fault zone. The following animation shows a birds eye view of a country road that cuts through an orchard. This lesson plan demonstrates stickslip or elastic rebound theory through a classroom project. Measuring and predicting earthquakes, for kids, is up next. This is the principle that reid proposes through his elastic rebound theory of earthquakes. However, based on studies in the tonga islands, earthquakes occur within the weak, ductile asthenosphere. 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.
The energy liberated at the time of an earthquake was present there in the form of energy of elastic strain of the rock. In geology, the elasticrebound theory is an explanation for how energy is released during an earthquake. Video lecture by ross stein of the usgs exerpt from the video, shock waves. In geology, the elastic rebound theory is an explanation for how energy is released during an earthquake. Earthquake precursors in the light of peroxy defects theory arxiv. Some of what you will be tested on includes tectonic plates and elastic rebound theory. Where does rock behave as an elasticplastic material. Presently, no models of normal fault earthquake cycles exist, and in. Who observed what and where to arrive at the idea of elastic rebound. 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. Elastic rebound theory in plate tectonics was introduced in 1906 by h. Elastic reboundtheory elasticrebound theelasticreboundtheoryisanexplanationforhow energyisspreadduringearthquakes. 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. Earthquake classroom activities and lesson plans geology.
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