Efficient Parallel Implementation of Multi-Arrival 3D Prestack Seismic Depth Migration

Alexander L Pleshkevich ,V D Levchenko ,Sergey A Khilkov ,А В Иванов ,Boris P Moroz

doi:10.14529/jsfi190101

Abstract

The goal of seismic migration is to reconstruct the image of Earth's depth inhomogeneities on the base of seismic data. Seismic data is obtained using shots in shallow wells that are located in a dense grid points. Those shots could be considered as special point sources. A reflected and scattered seismic waves from the depth inhomogeneities are received by geophones located also in a dense grid points on a surface. A seismic image of depth inhomogeneities can be constructed based on these waves. The implementation of 3-D seismic migration implies the solution of about 10 4÷5 3-D direct problems of wave propagation. Hence efficient asymptotic methods are of a great practical importance. The multi-arrival 3-D seismic migration program is implemented based on a new asymptotic method. It takes into account multi-pass wave propagation and caustics. The program uses parallel calculations in an MPI environment on hundreds and thousands of processor cores. The program was successfully tested on an international synthetic SEG salt data set and on real data. A seismic image cube for Timan-Pechora region is given as an example.

Highlights

Among all the tools applied for oil and gas exploration at the moment seismic prospecting is the most accurate and widely used method to study the structure of the inhomogeneous Earth’s medium
Seismic imaging implementation based on reflected and scattered seismic waves from the depth geological structures is known as a seismic migration
Geophones on the surface register scattered and reflected waves from the depth inhomogeneities. These waves are produced by special shots in shallow wells as sources

Summary

Introduction

Among all the tools applied for oil and gas exploration at the moment seismic prospecting is the most accurate and widely used method to study the structure of the inhomogeneous Earth’s medium. Seismic imaging implementation based on reflected and scattered seismic waves from the depth geological structures is known as a seismic migration. Geophones on the surface register scattered and reflected waves from the depth inhomogeneities. These waves are produced by special shots in shallow wells as sources. The seismic migration process demands to solve numerous problems of wave propagation in heterogeneous medium. It is common practice to use a singlebeam assumption. It states that there is only one ray from the source to an arbitrary point in the medium, the one which passes through the point at the shortest time. The seismic migration based on this approach and its efficient implementation are the main topics of the authors’ research

Formulation of Seismic Migration

Algorithm and Implementation Specific Features

Conclusion