Seismic Wavefield Separation Using Dual-Stage Processing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for separating up- and down-going wavefields in seismic data acquisition are inadequate when using multicomponent seismic data, which includes pressure and particle motion measurements, as they fail to accurately process particle motion data and introduce noise, leading to inaccurate subsurface imaging.
Innovation Solution
A method involving two wave-field separation processes, where the second process is constrained by the first, using hydrophone and particle velocity data to improve the accuracy of subsurface imaging by separating up- and down-going wavefields independently and then using the output for further processing, incorporating low-cut and high-cut filters to reduce noise and obliquity corrections.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If existing methods for separating up- and down-going wavefields are used with multicomponent seismic data, then pressure data can be processed, but particle motion data introduces noise and reduces accuracy
Solution Approach 1:
The wavefield separation is divided into two independent processes: a first separation that processes pressure and particle motion data independently, and a second separation that combines their outputs. This segmentation allows each process to optimize for its specific data type, reducing noise propagation from particle motion data while preserving accurate pressure data processing.
Solution Approach 2:
The first wavefield separation acts as an intermediary process that prepares cleaned wavefield components before they are combined in the second separation. This intermediary step filters out noise from particle motion data while maintaining the useful information needed for accurate subsurface imaging.
2Measurement precision
If a single wavefield separation process is used, then processing is simpler, but accuracy of separating up- and down-going wavefields is insufficient
Solution Approach 1:
The processing system is segmented into two distinct wavefield separation processes, each optimized for specific aspects of the data. The first separation handles independent processing of pressure and particle motion data, while the second separation integrates their outputs. This segmentation improves accuracy despite increased complexity.
Solution Approach 2:
The outputs from the first wavefield separation process are merged as inputs to the second separation process. This combining allows the system to leverage the strengths of both pressure and particle motion data processing while maintaining independent optimization in each stage.
3Productivity
If particle motion data is processed without special handling, then all available data is used, but noise is introduced that degrades imaging quality
Solution Approach 1:
The processing methodology segments particle motion data handling into distinct stages: first separation processes it independently with appropriate filtering, then the second separation integrates it with pressure data. This segmented approach ensures full data utilization while maintaining reliability through noise reduction at each stage.
Solution Approach 2:
The first wavefield separation process applies partial processing to particle motion data, focusing on extracting useful information while filtering out noise. This partial action approach processes only the necessary components of particle motion data, avoiding over-processing that would introduce excessive noise.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Computing device, computer instructions and method for for up-down separation of seismic data. The method includes receiving (500) the seismic data, which includes hydrophone data and particle motion data; performing (502) a first up-down separation, which is independent of a ghost model, using as input the hydrophone data and the particle motion data, to obtain first up-down separated data; performing (504) a second up-down separation by using as input a combination of (i) the hydrophone data and/or the particle motion data and (ii) the first up-down separated data, wherein an output of the second up-down separation is second up-down separated data; and generating (506) an image of the subsurface based on the second up-down separated data.