Compressed Seismic Wavefields in 3D Reverse Time Migration

Abstract

A three-dimensional (3D) seismic data set is partitioned into a plurality of 3D source wavefield subsets, each 3D source wavefield subset being stored in an array element of the array. For each array element, decompose the associated 3D source wavefield into smaller data units; randomly shift the data boundaries of the smaller data units; apply folding operations and sample operators to the smaller data units, to prevent smaller data units from overlapping; smooth the folded smaller data units to generate smoothed data; perform a quantization operation on the smoothed data to generate quantized data; and compressively encode the quantized data to generate compressed data. The compressed data associated with each array element is decompressed to generate a 3D seismic output image.

Description

[0001] priority statement [0002] This application claims priority to US Patent Application No. 62 / 484,101, filed April 11, 2017, the entire contents of which are hereby incorporated by reference. Background technique [0003] Seismic imaging is a tool that bounces sound waves off subsurface structures, such as rocks and other sedimentary layers or cavities, to reveal possible oil-bearing formations. Reverse time migration (RTM) is a seismic imaging method that provides accurate imaging in and below regions of complex structures and velocities. In RTM, seismic images are generated by zero-delay cross-correlation of source and receiver wavefields. The source wavefield is computed by forward propagation, while the receiver wavefield is computed by backward propagation. Due to the opposite directions of propagation relative to the source and receiver wavefields, the RTM first computes data for the entire source wavefield and stores this data in a data storage location such as ...

AI Technical Summary

Problems solved by technology

This approach consumes significant computational resources (e.g., processor cycles, data bus bandwidth, computational memory (e.g., random access memory (RAM)), network bandwidth due to the need to read / write very large data sets to storage locations and data storage space)

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