Use of complex attrubute analysis as a faults’ detection instrument to localize tectonic traps

   Introduction. A significant number of faults having various amplitude and rank within the Pur-Taz oil and gas region were recently detected. Basic principles of fault mapping make it possible to identify few of them, mainly more major in terms of amplitude and contrast; the main problem remains the identification of low-amplitude faults and faults without displacement. Therefore, fault detection algorithms need to be improved, which allow analyzing the spatial position of faults based on seismic attributes comprehensive analysis.

   Aim. The aim of the work is to clarify the geological & tectonic structure of the site under consideration, as well as the impact of identifi ed faults on development.

   For this purpose, the authors propose the use of complex attribute analysis as instrument of faults’ detection with various ranks.

   Materials and methods. The methodology of fault identifi cation based on the complex analysis of seismic attributes, emphasizing noise suppression and amplifying signals of faults. The workfl ow is based on the selection of the sequence of calculation of attributes. The developed methodology consists of three main stages — data preparation and noise suppression, faults’ borders highlighting, faults detection and quality control.

   Results. The optimal workfl ow of calculating attributes has been developed. Complex attribute analysis as a tool for identifying disjunctive disorders was applied at one of the fi elds within the Pur-Taz region. According to the results of the interpretation of tectonic disturbances in the work area, about 30 % of new faults were additionally identified. Moreover, the geometry of existing faults was clarifi ed.

   Conclusion. The authors propose the use of complex attribute analysis as a tool for identifying faults in order to localize structural and tectonic traps. Additionally, an analysis of the impact on the development of accounting for identified violations was carried out.

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