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Robust Interbed Multiple Modelling and Attenuation for Variable-Density Surveys Onshore Oman
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 81st EAGE Conference and Exhibition 2019, Jun 2019, Volume 2019, p.1 - 5
Abstract
Pre-stack multiple modelling and attenuation remains a significant challenge for processing and imaging of onshore seismic surveys. Due mainly to noise in the data, as well as irregular and incomplete spatial sampling, pre-stack applications seem to lag behind the relatively complete theories available to model internal multiples. In practice, generation of inaccurate multiple models that are subsequently adapted to the data can easily cause signal damage where dip discrimination between primaries and multiples is low. This is often diagnosed by appreciable distortion of the multiple model during adaption. Using data from onshore Oman, pre-stack multiple modelling and attenuation performed with variations of the predictive deconvolution and correlation-convolution methods produce accurate multiple models that undergo little distortion during adaption. The methods appear robust for pre-stack use, with the eventual aim of both structural and AVO analysis of the data. Results were achieved with careful attention to the mechanics of the data-driven predictions, and by limiting the freedom of the methods to react to noise in the gathers. Improvements to the stability of AVO analysis were due particularly to increased fidelity of near-angle data.