Rupture propagation animation of the 2004 sumatraandaman earthquake as imaged by the hinet array. Probabilistic seismic hazard map calculations using 3d. The software used to simulate the seismic wave propagation is. Shakemap is a product of the usgs earthquake hazards program in conjunction with the regional seismic networks. Then the user can select go to start the animation or can select which stations to use and which components for each station. By carefully examining these seismic wave fronts and their propagation, the seismic waves tool illustrates how earthquakes can provide evidence that allows us to. Acoustic fdtd solver ac2d is a software to simulate acoustic wave propagation in two dimensions based on the finitedifference timedomain fdtd method.
The p waves travel with the fastest velocity and are the first to arrive. Earth can also be illustrated effectively using the simulation software seismic waves. We present important extensions of the software seissol based on the arbitrary highorder discontinuous galerkin dg finiteelement method to model seismic wave propagation using nonconforming. Some of the wave energy reflects off the boundary between the mantle and core. We measure these waves with seismometers when they interact with the surface and cause the ground to move ground motion. Various algorithms are used to carry out elastic modeling of seismic wave propagation, allowing us to fully understand all aspects of the recorded information. S waves, known as secondary waves, are seismic waves that simply go about in an s shape, form, and is the second wave to arrive during an earthquake.
Usgs earthquake hazards program, responsible for monitoring, reporting, and. Seismic wave motions4 waves animated iris consortium. These animations are based on a simulated magnitude mw 7. The calculation is based on numerical solution of equation for a complex phase of the wave. This animation, called a ground motion visualization gmv, shows the motion of the ground as detected on seismometers across north america each dot is a seismic station and when the ground moves up it turns red and when it moves down it turns blue. Examine p and s waves moving through earths interior. An earthquake generates a series of seismic waves that travel through the interior or near the surface of the earth.
The propagation velocity of seismic waves depends on density and elasticity of the medium as well as the type of wave. We concatenated the frames into animations with the software mencoder using. The animations below illustrate both the propogation of the wave as well as the motion of. Seissol is a software package for simulating wave propagation and dynamic. The resulting ground motion collection will be processed, using sceccme software tools, into probabilistic seismic hazard maps for the region under study. Visualizing wave propagation file exchange matlab central. This code is equipped with a frequencyindependent attenuation model based on the. The animation also identifies the regions of compression and rarefaction. This is useful in several disciplines, including earthquake and oil exploration seismology, ocean acoustics, radar imaging, nondestructive evaluation, and others. P waves travel faster than other seismic waves and hence are the first signal from an earthquake to arrive at any affected location or at a seismograph. If an earthquake has large enough spatial and temporal extent, the rupture propagation can be imaged with great detail using this technique. This computer simulation shows how the seismic waves of the oct 30th 2018. Body waves include p and s waves, and these are the two types of waves that are used to determine the internal structure of the earth.
Seismic wave propagation is a ground motion phenomenon that relates to the passage of body waves, including compression waves and shear waves, radially from the source of earthquake energy release hypocenter into the surrounding rock and soil medium. Seismic waves are studied by geophysicists called seismologists. The earthquake depth is 600 km and the focal mechanism has a dip of 45 degrees, a slip of 0 degrees, and strike perpendicular to the direction of propagation. This work shows the strong effect of including the variation of wave speed through the top thirty meters of the earth. These highlight aftershocks and seismic wave propagation. Animations of seismic wave propagation home university of utah. Modeling of seismic wave propagation at the scale of the.
The below animation shows the propagation of a vertically polarized s wave. Animations illustrating simple wave propagation concepts propagation. This animation produced in conjunction with kqeds quest series, walks viewers through an easy to understand, playful introduction to earthquake basics and various different seismic waves. The package has a sequence of 6 models that have both a transient pulse excitation as well as a sine wave excitation. P waves, known as primary waves, are also part of a seismic wave. Seismic waves, shadow zone of pwaves and swaves pmf ias. P waves, also called compressional waves or primary waves, move through material by squeezing and stretching the material in the same direction as the wave is moving. We will show that two types of solutions are possible, corresponding to compressional p and shear s waves, and we will derive the. A wave set is a wave and some key waves that precede it.
Then the user can select go to start the animation or can select which stations to use and. Seismic waves viewer open resource seismic waves is a browserbased tool to visualize the propagation of seismic waves from historic earthquakes through earths interior and around its surface. Shakemaps provide nearrealtime maps of ground motion and shaking intensity following significant earthquakes. Details on the fault parameters and subsequent analysis at seattle and tacoma, washington, are available in titov et al.
These highlight aftershocks and seismic wave propagation, respectively, but potentially introduce distortions in the near field while permanent displacements are still accumulating. Animations are provided to view wave propagation in a 3dimensional solid for compressional p, shear s, rayleigh r and love l waves. This is an acoustic wave propagation model, but by using s wave velocities, it provides an adequate though incomplete simulation of sh wave propagation. Easytouse controls speedup, slowdown, or reverse the wave propagation.
Surface wave, rayleigh and love, propagation animations. Seismic waves is a browserbased tool to visualize the propagation of seismic waves from historic earthquakes through earths interior and around its surface. The raytracing, however, is helpful in following individual packets of energy, and helps in understanding the generation of travel time curves, which show the arrival times of phase as functions of distance traveled. The user can select from one of several earthquakes distributed with the program. Codes for wave propagation and earthquake dynamics. This program is necessary to calculate of xrays wave focusing by xray microscope. A visualization of earthquake waves traveling both through earths interior and radiating outward on the surface.
Iris authored software community authored software. An earthquake generates seismic waves that penetrate the earth as body waves p. S waves, also called shear waves or secondary waves, move materials at right angles to the wave direction. The velocity model is from wald, et al bssa 81,15401572, 1991 with the top layer removed. Is there any software or codes for modeling the seismic. Seismic waves is a windows program which illustrates how waves propagate from an earthquake hypocenter to seismic stations throughout the earth. Global seismic wave propagation simulations were computed with the shaxi and psvaxi methods. Here is an animation of s wave amplification at san francisco due to the loma prieta earthquake. Seismic wave propagation an overview sciencedirect topics.
For the numerical simulation of 2d earthquake dynamics, the spectral boundary integral equation code bimat is well suited for planar faults in homogeneous and bimaterial media, and the spectral element code sem2dpack is well suited for nonplanar faults in heterogeneous or nonlinear media. Seismic waves are fundamentally of two types, compressional, longitudinal waves or shear, transverse waves. A scientific software for the numerical simulation of seismic wave phenomena. Use the movie controls to examine the motion of the waves. Seismic wave animations are used to illustrate different types of wave propagation through elastic materials.
Note that an s wave could also be horizontally polarized, meaning that particle motion would be in the y direction in the coordinate system of the animation, as opposed to the z direction for vertical polarization. This simulation shows the motion of p and s waves generated by a single earthquake. The second animation at right shows the difference between the oscillatory motion of individual particles and the propagation of the wave through the medium. The wavefront observed by the array is collapsed back in space and time backprojected to the target region to determine the timing and location of the energy source that generated the seismic waves. P waves may be transmitted through gases, liquids, or solids nomenclature.
It illustrates how earthquake waves propagate through the earth. S waves cannot travel through liquids, they can travel through solids. A series of animations is presented here, which show the way that seismic shear waves propagate through the mantle of the earth from an earthquake. Software development that made the production of these animations. This wave equation is solved using the finitedifference method a 2nd order stencil with the purpose of modeling wave propagation in the medium. Seismic waves earthquakes discovering geology british. The waveform animation gives an intuitive sense of the true wave propagation, including relative wave amplitudes. There were challenging logistics in planting and cabling them, and in their recording with three times the normal number of channels. Wave propagation is a natural phenomenon that is important in many physical systems. Animations are provided to view wave propagation in a. A p wave is one of the two main types of elastic body waves, called seismic waves in seismology. There are other types of seismic waves, but they relate to surface damage and only travel through the earths crust, not the entire.
Wave propagation in the earth an earthquake emits elastic energy in the form of waves seismic waves. Seismic wave fields are recorded by a seismometer, hydrophone in water, or accelerometer. The shaxi source code can be downloaded at the spice webpage. Seismic wave propagation in a spherically symmetric earth model.
The propagation of shear s and compression p waves within the earth allows geologists to track seismic events and to identify subterranean structure. The p waves primary waves in an earthquake are examples of longitudinal waves. The animations below show coordinate variations every 1 sec. This rupturing process creates elastic waves in the earth that propagate away from the rupture front at a. This activity includes both the seismic waves viewer and the seismic eruption software to help learners better understand earthquakes, volcanoes, and the structure of the earth. To model the seismic wave propagation in random media, what software. Seismic waves viewer incorporated research institutions. The animations below illustrate both the propogation of the wave as well as the motion of particles as the wave passes. We advise comparison to animation s1 before drawing conclusions about near. Is there any software or codes for modeling the seismic wave propagation in 3d random scattering media. Ppt seismic%20waves powerpoint presentation free to. We have developed an opensource software package, opensource seismic wave propagation code openswpc, for parallel numerical simulations of seismic wave propagation in 3d and 2d psv and sh viscoelastic media based on the finite difference method in localtoregional scales.
The work described in this page is based on using the sw4 or wpp codes, which implement many of the numerical discretization techniques from our project see our theory and software pages. The codes of subprograms in c, which simulate the xrays wave propagation through berillium lenses and air. The waves spread through the planet in a series of expanding spheres. Each wave has a characteristic speed and style of motion. One sees waves propagating out from the epicenter on a threedimensional view of the earth at the same time one sees waves propagating through a crosssectional view of the earth. Text books leave much to be desired regarding visualization of wave propagation since they are not animated. The seismic wave equation using the stress and strain theory developed in the previous chapter, we now construct and solve the seismic wave equation for elastic wave propagation in a uniform whole space. Seismic wave propagation an important application of our wave propagation work is the visco elastic wave equation, which governs seismic wave propagation. By carefully examining these seismic wave fronts and their. Seismic waves viewer incorporated research institutions for.