US 2013/0279293 A1 · VECTORIZATION OF FAST FOURIER TRANSFORM FOR ELASTIC WAVE PROPOGATION FOR USE IN SEISMIC UNDERWATER EXPLORATION OF GEOGRAPHICAL AREAS OF INTEREST

Abstract

Numerical simulations of elastic wave propagation algorithms are critical components for seismic imaging and inversion. Finite-difference schemes yield good efficiency but cannot ensure the accuracy of the high frequency component. Pseudo-spectral algorithms are accurate up to the Nyquist frequency, but its efficiency depends on the optimization of the fast Fourier transform (FFT) algorithm. The conventional FFT algorithms are optimized for signal processing, in which problems are generally one dimensional time series. For 3D wave propagation, FFT algorithms have the potential to be further optimized. Under current computer hardware architecture, a vectorization scheme for high dimensional FFTs is presented. Compared to conventional numerical scheme implementations, the systems and methods disclose herein has the best performance on the slowest or higher dimensions of data. For elastic wave propagation, vectorization improves the efficiency by more than a factor of two when compared to standard FFT algorithms.

Claims16

Dependent claims

A method for simulating and displaying wave propagation using reflection seismology in a geographical area of interest, the method comprising:

converting signals associated with marine seismic soundwaves into digital electronic form, and storing the same as single precision floating numbers in an array of size N;
converting the real array of size N into a complex array of size N/2;
determining a first derivative of the following elastic wave equation—
ρ

(
x
)

∂
2

u
i
∂
t
2
-
∂
∂
x
j

C
ijkl

∂
∂
x
l

u
k
=
f
i
using the following equation—
Z
k
′
=


(
N
4
+
N
4

sin

2

π


k
N
-
k
)

Z
k
+
N
4

cos

2

π


k
N

Z
k
†
*
wherein said determination of the first derivative includes the determination of a fast fourier transform using an FFT vectorization scheme;
using the calculated derivatives of the elastic wave equation to determine wavefield propagation underground;
and
processing the calculated derivatives into data that can be used to display the determined wavefields so that underground geographical features in the underground geographical area of interest can be determined.

84 more elements

A system for simulating and displaying wave propagation using reflection seismology in a geographical area of interest, the system comprising:

a processor configured to convert signals associated with marine seismic soundwaves into digital electronic form, and storing the same as single precision floating numbers in an array of size N, and wherein the processor is further configured to
convert the real array of size N into a complex array of size N/2;
determine a first derivative of the following elastic wave equation—
ρ

(
x
)

∂
2

u
i
∂
t
2
-
∂
∂
x
j

C
ijkl

∂
∂
x
l

u
k
=
f
i
using the following equation—
Z
k
′
=


(
N
4
+
N
4

sin

2


π


k
N
-
k
)

Z
k
+
N
4

cos

2

π


k
N

Z
k
†
*
wherein said determination of the first derivative includes the determination of a fast Fourier transform using an FFT vectorization scheme, and further wherein the processor is further configured to
use the calculated derivatives of the elastic wave equation to determine wavefield propagation underground, and
process the calculated derivatives into data that can be used to display the determined wavefields so that underground geographical features in the underground geographical area of interest can be determined.

84 more elements

Dependencies are inferred from the claim text.

Vectorization of fast fourier transform for elastic wave propogation for use in seismic underwater exploration of geographical areas of interest

Life of this patent

Vectorization of fast fourier transform for elastic wave propogation for use in seismic underwater exploration of geographical areas of interest

Life of this patent

Abstract

Claims16