seismic wave propagation on the tablet computeremoto/material/poster_agu2015.pdf · 2015-12-11 ·...

, : Lame parameter: Velocity, : Stress, : Density

Seismic Wave Propagation on the Tablet Computer T13D - 3041

Kentaro EMOTO (Geophys, Science, Tohoku University, Japan) emoto@zisin.gp.tohoku.ac.jp

Name: Seismic WaveRelease: 1 April 2015Category: EducationSize: 1.5 MB

Simulator of the seismic wave propagation in 2D.

Intuitive, Accessible, Interactive, Simple

iPad App

- Special knowledge is not necessary- Double-couple source- Propagation of P, S and surface waves- Reflection, refraction and transmission- Scattering due to the heterogeneous structure

iPad AirCPU: Apple A7

(1.4 GHz, dual-core)Memory: 1 GB

App usageCPU: ~ 180 %Memory: 80 ~ 100 MB

- High performance (CPU, Memory, Rendering)- Parallel computing- Enough for the small 2D numerical simulation (Simultaneous calculation and rendering)- Complex & professional simulations PC or supercomputer

- Staggered-grid finite difference scheme (Solve the velocity & stress at every half time step, alternately)- Precision: 2nd order in both time & space- Velocity structure: 3 layers- Boundary: Absorbing (side & bottom), Free surface (top)- Source: double-couple point source- Receiver: recording the x & z-component velocity (plot the waveform in real time)

Equation of motion

Required time for 2000 steps (20s)

Grid

Draw

300

150 x 1 px 300 x 1 px 150 x 2 px 300 x 1 px 300 x 2 px

- Calculate P and S wave energy by taking div. and rot.- Draw the wavefield every 20 steps- Asynchronous drawing- Calculation time grid size & image resolution

300 300 600 300

- Movable Layer boundary Receiver & source

- Variable Fault geometry Source time function

- Variable Colors of wavefields Layer velocity

- Save & load Favorite structure Image of the wavefield

- Advanced Random fluctuation Scattering Variable PSDF Any type of random

- Future development Movable topography Multiple receivers Array analysis Multiple sources Finite fault Tsunami (2D simulation)

地震

10s

20s

30s