Seismic Interferometry for Surface Multiple Removal in OBC Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current techniques for removing surface multiples from seismic data, such as SRME, are ineffective when sources and receivers are spaced far apart, as in ocean bottom node (OBN)/ocean bottom cable (OBC) acquisitions, due to the requirement for surface consistency, which is not always feasible due to cost or practical limitations.
Innovation Solution
Applying seismic interferometry to generate additional seismic data that simulates surface consistent data, allowing for the prediction and removal of surface multiples without the need for companion streamer surveys, by cross-correlating wave field observations at different receiver locations to construct the necessary ray paths for Surface Related Multiple Elimination (SRME) processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional SRME techniques are used to remove surface multiples, then surface consistency is required for effective multiple elimination, but this requirement cannot be met in OBC acquisitions where sources and receivers are spaced far apart
Solution Approach 1:
The patent creates a virtual copy of the streamer acquisition geometry by using seismic interferometry to synthesize streamer-like data from OBC data. This virtual copy allows SRME to be applied indirectly - the synthesized data undergoes SRME processing, and the results are then used to predict and remove multiples from the actual OBC data, bypassing the surface consistency requirement for the original OBC acquisition
Solution Approach 2:
The patent introduces an intermediary step of seismic interferometry that bridges the gap between OBC data and SRME requirements. The interferometry process acts as a mediator that transforms OBC data into a form that satisfies SRME's surface consistency assumption, enabling multiple elimination without requiring the actual OBC acquisition to meet this assumption
2Reliability
If companion streamer surveys are conducted to provide surface consistent data for SRME, then surface consistency requirement is satisfied, but acquisition cost and complexity increase significantly
Solution Approach 1:
Instead of acquiring actual companion streamer data, the patent creates a virtual copy through seismic interferometry. This synthesized data provides the necessary surface consistency for SRME processing without requiring physical streamer deployment, thereby eliminating the additional acquisition complexity and cost while maintaining the reliability needed for effective multiple removal
3Area of stationary object
If sources and receivers are spaced far apart in OBC acquisitions, then subsurface imaging coverage is improved, but surface multiple removal becomes ineffective due to violation of surface consistency assumption
Solution Approach 1:
The patent creates a virtual streamer geometry copy that restores surface consistency while preserving the wide spacing benefits of OBC acquisition. The interferometry-based synthesis generates data that appears as if collected by closely-spaced streamers, allowing SRME to effectively remove multiples even though the actual physical spacing remains large for improved subsurface coverage
Solution Approach 2:
The patent effectively changes the geometric parameters of the data through interferometric transformation. By converting OBC data into an equivalent streamer geometry representation, the apparent source-receiver spacing is transformed, allowing the data to satisfy surface consistency assumptions without physically altering the original acquisition geometry that provided broad subsurface coverage
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables the effective removal of surface multiples from seismic data acquired using OBC systems, improving the accuracy of subsurface imaging by generating surface consistent data that can be used for SRME, even in scenarios where traditional methods fail due to source/receiver spacing issues.
Implementation Method 1
performing seismic interferometry on the received seismic data to generate additional seismic data
Implementation Method 2
by cross-correlating wave field observations at different receiver locations to construct the necessary ray paths
Data Source
AI summary
A system and method are disclosed for predicting, and optionally removing surface multiples from acquired seismic data that lacks surface consistency, such as seismic data acquired using an Ocean Bottom Cable (OBC) or Ocean Bottom Node (OBN) system where the sources are located at or near the water's surface and the receivers are located at or near the ocean's floor. By processing the acquired seismic data using seismic interferometry, source side and/or receiver side operators can be generated which satisfy the surface consistency requirement of techniques such as Surface Related Multiple Elimination (SRME) so that SRME or the like can be used to predict the surface multiples.