Pdf on incorrectness in elastic rebound theory for cause. Learning earthquake tip 1 earthquake design and construction. What makes an elastic rebound possible during an earthquake. Characterizing earthquake sources a elastic rebound. The elastic rebound theory of earthquake sources allows rough prediction of the occurrence of large shallow earthquakes. Reid gave, for example, a crude forecast of the next great earthquake near san francisco. Prior to an earthquake it was noted that the rocks adjacent to the fault were bending. However, based on studies in the tonga islands, earthquakes occur within the weak, ductile. When the strength of the rock is exceeded, it suddenly breaks, releasing some of its stored energy as seismic waves. The three types of directional stress experienced by rocks are compressional, tensional, and shear stress fig. Elastic rebound theory waves generated by earthquakes. The mechanisms and processes involved when earthquakes occur are extremely complex.
These intraplate earthquakes are caused by stresses within a plate. Over time stresses in the earth build up often caused by the slow movements of tectonic plates. Earthquakes are caused by plate interactions along tectonic plate. These bends disappeared after an earthquake suggesting that the energy stored in bending the rocks was suddenly released during the earthquake. What kinds of seismic waves are produced by earthquakes. When the stress becomes too great then the rocks separate and an earthquake results. As the earths crust deforms, the rocks which span the.
The elastic rebound theory states that pressure builds in rocks on opposite sides of a fault until. Elastic rebound theory earthquake locations are determined using triangulation from geos 1004 at virginia tech. Anatomy of an earthquake focus the location within earth along a. It is only partially correct because it associates earthquakes with geological faults. Reid see box below to explain how energy is released during earthquakes. Type of faults dip slip faults strike slip faults figure 6.
Earthquake precursors in the light of peroxy defects theory arxiv. The theory also predicted, of course, that the place would be along read more. 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. 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. Evaluate the knowledge you have gained about the causes of earthquakes with this quiz and worksheet.
At some point the stresses become so great that the. According to elastic rebound theory, earthquakes are generated when the rocks slide with each other at an instant where as it happens for a long period it would cause deformation in the rocks. 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. Reids elastic rebound theory, we now know that earthquakes are not completely. List the key observations that revealed earth to possess a. Elastic reboundtheory elasticrebound theelasticreboundtheoryisanexplanationforhow energyisspreadduringearthquakes. 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. The amplitude of the pwave displacement is used to determine the. 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. Lecture 16 earthquakes lecture 16 earthquakes what are earthquakes. For a century, the elastic rebound theory has been a foundation on which later seismic hypotheses were. Faults act like scars, they remain weaker than the surrounding crust. Reids elastic rebound theory rocks store elastic energy until they cannot store it any longer, then snap like a rubberband. As rocks on oppo site sides of a fault are subjected to force and shift.
Reids elastic rebound theory not only allowed to explain the. The gradual accumulation and release of stress and strain is called the elastic rebound theory of earthquakes. Previously it was thought that ruptures of the surface were the elastic rebound theory. Life after death experience nde with steve gardipee, vietnam war story one of the best ndes duration. Illuminates the causes of earthquakes by elastic rebound theory and earthquake location as focus and epicenter. Reids elastic rebound theory usgs earthquake hazard program.
Explain the elastic rebound theory, which provides an explanation for the origin of earthquakes. How rocks respond to stress is a fundamental concept, critical to forming explanatory models in the geosciences e. Slowly they deform, until their internal rigidity is exceeded. About 5% of earthquakes take place within a plate, away from plate boundaries. How is the elastic rebound theory related to earthquakes. The description of how earthquakes occur is called elastic rebound theory figure 1. Describe the characteristics of seismic waves and explain the difference between primary waves, secondary waves, and surface waves. An earthquake rupture occurs and relieves some of the stresses but generally not all. Some of what you will be tested on includes tectonic plates and elastic rebound theory. Elastic rebound theory earthquake locations are determined. The elastic rebound theory explains remarkably well the overall nature of major earthquakes. Elastic rebound theory in plate tectonics was introduced in 1906 by h. D all of the above elastic rebound theory suggests.
The force per unit area acting on a rock is called stress. 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. Following this concept, elastic dislocation models e. Nov 17, 20 the elastic rebound theory predicts that earthquakes can be generated only in the lithosphere. It is the first theory that explains why earthquakes happen. It can be done in small groups or as a classroom demonstration, with students recording data. 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. The elasticrebound theory of earthquakes harry fielding. Intraplate earthquakes happen along these zones of weakness. 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. The elastic rebound theory of earthquakes bulletin of the department of geology, calif university of california. Stresses build on both sides of a fault, causing the rocks to deform plastically time 2.
The more stress built up the greater the quake magnitude. Like all theories in any branch of physics, theories of the seismic source should be testable i. In elastic rebound theory, what must occur to produce an. Large thrust earthquakes generally occur along subduction zones where. Due to the motion of the earths tectonic plates, the ground beneath our feet is always moving, just too slow and g. 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. Tectonic movement, whether it is a divergent, convergent, or transform boundary, causes the plates to move and build up stress. Elastic rebound and friction lab lesson plan by deborah kane and dave van dusen. Previously it was thought that ruptures of the surface were the result of strong ground shaking.
The elastic rebound theory was developed 100 years ago from the observations of coseismic surface ruptures induced by the 1906 california earthquake. In geology, the elastic rebound theory is a theory which tries to explain why earthquakes occur. Earthquakes happen when so much stress builds up in the rocks that the rocks rupture. However, it is inconsistent and even violates many other phenomena that were present before, during and after earthquakes.
Aug 02, 2018 elastic rebound theory in plate tectonics was introduced in 1906 by h. This activity helps learners see the elastic properties of rocks by actually bending marble. Elastic rebound theory elastic rebound the sudden return of elastically deformed rock to its undeformed shape earthquakes occur when rocks under stress suddenly shift along a fault. Why we need a new paradigm of earthquake occurrence. 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. An earthquake is sudden ground movement caused by the sudden release of energy stored in rocks, called the elastic rebound theory. This is the principle that reid proposes through his elastic rebound theory of earthquakes. 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. 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.
The arrival of earthquakes waves is recorded by a seismograph. When the stresses become too great, the rocks break and end up in a different location time 3. From an examination of the displacement of the ground surface which accompanied the 1906 earthquake, henry fielding reid. Elastic rebound theory this theory was discovered by making measurements at a number of points across a fault. 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. The elasticrebound theory of earthquakes bulletin of. Duponts plasticslip theory rocks store bending energy until they cannot store it any longer, then snap like a rubber ball. This scenario can happen repeatedly on a 100500 year cycle. Ppt elastic rebound theory powerpoint presentation.
Most of the motion along faults can be explained by the plate tectonics theory. P waves, s waves, surface waves locating earthquakes. Observation and interpretation of precursory phenomena. Elastic rebound theory is directly related to earthquakes. The elastic rebound theory predicts that earthquakes can be generated only in the lithosphere. Elastic rebound theory rocks at the edges of tectonic plates are subject to tremendous forces resulting in intense deformation. By combining seismicity data for more than 100 active fault. It is a way for the stored energy to be released through a sudden action. 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 occurrence of tectonic earthquakes can be explained by the theory of elastic rebound, first advanced by h. Earthquakes are vibrations of the earth caused by the sudden release of energy, usually along a fault. Each year there are more than 150,000 earthquakes strong. 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 tectonic plates are made of elastic but brittle rocky material. 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. D all of the above elastic rebound theory suggests that. 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. In other instances, they rupture large sections of faults, combining patches that had not been known to. In the theory, fault movements are based on the ability of rock to stick to each other while under stress. 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. As the earths crust deforms, the rocks which span the opposing sides of a fault are subjected to shear stress.
Elastic rebound theory is the concept that earthquakes happen because stresses build up, causing rock to bend elastically until slip on a fault occurs. Earthquakes occur when strain exceeds the strength of the rock and the rock fractures. When the in geology, the elastic rebound theory was the first theory to satisfactorily explain earthquakes. Dows recovery theory rocks recover violently when a mass collides with them. Henry fielding reid, professor of geology at john hopkins university, baltimore developed the elastic rebound theory discussed. Reid, university of california publications, bulletin of the department of geology, 6, 19, 1911. A fault is a break in a body of rock along which one block moves relative to another. However some of the characteristics of earthquakes can be explained by using a simple elastic rebound theory. Reids elastic rebound theory usgs earthquake hazards. That low rumbling emanating from california is no earthquake. How do earth scientists explain this contradiction. According to the elastic rebound model, earthquakes are.
Earthquake prediction is a branch of the science of seismology concerned with the specification of the time, location, and magnitude of future earthquakes within stated limits, and particularly the determination of parameters for the next strong earthquake to occur in a region. Video lecture by ross stein of the usgs exerpt from the video, shock waves. Elastic strain buildup and brittle rupture stage b figure 7. According to the elastic rebound model, earthquakes are caused by energy released when a. The plate moves over a spherical surface, creating zones of weakness. The elastic rebound theory is an explanation for how energy is spread during earthquakes.
When bending rocks fails, the stress energy releases in the form of the earthquake. Similarly, the crust of the earth can gradually store elastic stress that is released suddenly during an earthquake. 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. Elastic rebound theory turkey, 1999 elastic deformation. Prior to a rupture event producing an earthquake, a body of rock experiences a certain amount of elastic deformation during which energy is stored strain energy. Basically elastic rebound is the primary reason earthquakes even happen. Earthquakes are caused by active faults, which are, caused by the sudden movement of the two sides of a fault with respect to another. In geology, the elastic rebound theory is an explanation for how energy is released during an earthquake. Earthquakes can be caused by faults, the motion of magma, and explosions e. Most earthquakes are the result of the sudden elastic rebound of previously stored energy.
This gradual accumulation and release of stress and strain is now referred to as the elastic rebound theory of earthquakes. This activity was developed for use in a high school grades 912 earth science class. On incorrectness in elastic rebound theory for cause of. According to the elastic rebound hypothesis most earthquakes. 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. The stored elastic energy has to go somewhere because it has been suddenly released. Earthquake research institute, tokyo university, tokyo, japan. However, based on studies done in the tonga islands, earthquakes occur within the weak, ductile asthenosphere.
This lab exercise teaches students about elastic rebound and friction and how these concepts related to earthquakes. Learn vocabulary, terms, and more with flashcards, games, and other study tools. In geology, the elasticrebound theory is an explanation for how energy is released during an earthquake. Stickslip behavior describes when earthquakes occur due to slip on a preexisting fault. Terms in this set 11 how does the elastic rebound theory explain the occurrence of earthquakes. In geology, the elastic rebound theory was the first theory to satisfactorily explain earthquakes.
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