Multiple Attenuation and Imaging Using Incomplete Seismic Data

Abstract

Current models based on target structures use bidirectional or unidirectional wave propagators to generate synthetic survey data. The current model is modified to reduce a difference between the synthetic survey data and the observed survey data while maintaining a velocity component of the current model constant, wherein the modification to the current model produces a modified model. The modified model is used to reduce the adverse effect of multiples in the target structure, or to promote the beneficial effect of multiples in the target structure.

Description

Background technique [0001] Seismic surveys are used to image subsurface portions and / or identify subsurface elements of interest, such as hydrocarbon reservoirs, freshwater aquifers, gas injection zones, and the like. In seismic surveying, seismic sources are activated to generate seismic waves that are directed into subsurface structures. [0002] Seismic waves generated by seismic sources travel into the Earth's subsurface structure, where a portion of the seismic wave is reflected by the subsurface rock structure back to the surface, where it is detected by seismic sensors (e.g., geophones, accelerometer, etc.) to receive. These seismic sensors generate signals representative of detected seismic waves reflected from subsurface structures. Signals from the seismic sensors may be processed to obtain information about the contents and properties of subsurface structures and / or to generate images of the subsurface. In order to process information about the content and prope...

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