High Performance Seismic Trace Compression
P. L. Donoho, R. A. Ergas, and J. D. Villasenor
We have developed an algorithm for the compression of seismic data capable of
compression ratios in excess of 100:1 for a wide range of datasets representing
both prestack and poststack data. Although the compression algorithm is lossy,
in the sense that its use introduces noise into the final reconstituted dataset,
the compression noise leads to no observable loss of geophysical information at
compression ratios substantially greater than 1OO:1. The compression algorithm
employs the wavelet transform to represent the data in a basis characterized by
a number of subbands having different temporal and spatial frequency content.
The coherency and redundancy of multidimensional seismic datasets, ranging from
prestack field data to migrated 3D stack cubes, permits efficient qantization of
the data by each wavelet-transform subband, such that a very small number of
bits per data sample will accurately represent the data. The ability to compress
data by such large factors leads to the possibility of transmitting entire field
datasets from a multistreamer marine survey directly to a processing center in
nearly real time. Complete 3D prestack datasets can be easily maintained online
with realizable disk storage at 100:1 compression ratio. Network transmission
and disk storage costs for other applications can also be reduced by large
factors. The algorithm described here has been optimized for speed in
compressing large 3D datasets, requiring typically the same amount of time as
other processing steps, such as NMO
.
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California