Multiples mitigation and imaging with incomplete seismic data

Abstract

Synthetic survey data is generated using a two-way or one-way wave propagator based on a current model of a target structure. The current model is modified to reduce a difference between the synthetic survey data and observed survey data, while maintaining unchanged a velocity component of the current model, where the modifying of the current model produces a modified model. The modified model is used to reduce an adverse effect of multiples in the target structure, or to promote a favorable effect of multiples in the target structure.

Description

Background technique [0001] Seismic surveys are used to image underground parts and / or identify underground elements of interest, such as hydrocarbon reservoirs, freshwater aquifers, gas injection areas, etc. In seismic surveys, seismic sources are activated to generate seismic waves that are directed into subsurface structures. [0002] The seismic wave generated by the seismic source travels into the subsurface structure of the earth, where a part of the seismic wave is reflected back to the surface by the subsurface rock structure, where a part of the seismic wave is generated by seismic sensors (e.g., geophones, Accelerometer, etc.) receive. These seismic sensors produce signals that represent the detected seismic waves reflected from structures below the surface. The signals from the seismic sensors can be processed to obtain information about the content and characteristics of underground structures and / or to generate images below the surface. In order to process informat...

AI Technical Summary

Problems solved by technology

However, prior seismic survey techniques did not compensate for lost recorded data when processing multiples as signals, and thus any area illumination gain from using multiples as signals was limited

[0006] Method error that uses recorded free surface multiples as signal (whether combined with recorded primary or not, and covers any processing or otherwise of internal multiples), but does not take steps to compensate for missing data accurately map some of the recorded free-surface multiples into subsurface structures, causing crosstalk or other types of noise in the seismic image

This noise degrades seismic image quality and can be difficult to remove

Images