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Post- and pre-stack attribute analysis and inversion of Blackfoot 3Dseismic dataset

The objective of this research is comparative analysis of several standard and one new seismic post- and pre-stack inversion methods and Amplitude Variation with Offset (AVO) attribute analysis in application to the CREWES Blackfoot 3D dataset. To prepare the data to the inversion, I start with processing the dataset by using ProMAX software. This processing, in general, includes static and refraction corrections, velocity analysis and stacking the data. The results show good quality images, which are suitable for inversion.<p>
Five types of inversion methods are applied to the dataset and compared. Three of these methods produce solutions for the post-stack Acoustic Impedance (AI) and are per-formed by using the industry-standard Hampson-Russell software. The fourth method uses our in-house algorithm called SILC and implemented in IGeoS seismic processing system. In the fifth approach, the pre-stack gathers are inverted for elastic impedance by range-limited stacking of the common-midpoint (CMP) gathers in offsets and/or angles and then performing independent inversion of angle stack. Further, simultaneous inversion is applied to pre-stack seismic data to invert for both the P- and S-wave impedances. These im-pedances are used to extract the Lamé parameters multiplied by density (LMR), and used to extract the ratios between the P- and S-wave velocities. In addition, CMP gathers are used to produce AVO attribute images, which are good indicators of gas reservoirs. Fi-nally, the results of the different inversion techniques are interpreted and correlated with well-log data and used to characterize the reservoir.<p>
The different inversion results show clearly the reservoir with its related low im-pedance within the channel. The post-stack inversion gives the best results; in particular, the model-based inversion shows smoothed images of it while SILC provides a different, higher-resolution image. The elastic impedance also gives results similar to the post-stack inversion. Pre-stack inversion and AVO attributes give reasonable results in cross sections near the center of study area. In other areas, performance of pre-stack inversion is poorer, apparently because of reflection aperture limitations.

Identiferoai:union.ndltd.org:USASK/oai:usask.ca:etd-10082009-155134
Date19 October 2009
CreatorsSwisi, Abdulsalam Amer
ContributorsMorozov, Igor
PublisherUniversity of Saskatchewan
Source SetsUniversity of Saskatchewan Library
LanguageEnglish
Detected LanguageEnglish
Typetext
Formatapplication/pdf
Sourcehttp://library.usask.ca/theses/available/etd-10082009-155134/
Rightsunrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to University of Saskatchewan or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.

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