Scale effects on modelling the seismic signature of gas: results from an outcrop analogue

Maria-Daphne Mangriotis, Colin MacBeth, Angel Briceno

Research output: Contribution to journalArticle

16 Downloads (Pure)

Abstract

Numerous examples of reservoir fields from continental and marine environments involve thin‐bedded geology, yet, the inter‐relationship between thin‐bedded geology, fluid flow and seismic wave propagation is poorly understood. In this paper, we explore the 4D seismic signature due to saturation changes of gas within thin layers, and address the challenge of identifying the relevant scales and properties, which correctly define the geology, fluid flow and seismic wave propagation in the field. Based on the study of an outcrop analogue for a thin‐bedded turbidite, we model the time‐lapse seismic response to fluid saturation changes for different levels of model scale, and explore discrepancies in quantitative seismic attributes caused by upscaling. Our model reflects the geological complexity associated with thin‐bedded turbidites, and its coupling to fluid flow, which in turn affects the gas saturation distribution in space, and its time‐lapse seismic imprint. Rock matrix and fluid properties are modelled after selected fields to reproduce representative field models with realistic impedance contrasts. In addition, seismic modelling includes multiples, in order to assess their contribution in seismic propagation through thin gas layers. Our results show that multiples could contribute significantly to the measured amplitudes in the case of thin‐bedded geology. This suggests that forward/inverse modelling involving the flow simulation and seismic domains used in time‐lapse seismic interpretation should account for thin layers, when these are present in the geological setting.
Original languageEnglish
Pages (from-to)1159-1179
Number of pages21
JournalGeophysical Prospecting
Volume66
Issue number6
Early online date26 Apr 2018
DOIs
Publication statusPublished - Jul 2018

Fingerprint Dive into the research topics of 'Scale effects on modelling the seismic signature of gas: results from an outcrop analogue'. Together they form a unique fingerprint.

  • Cite this