ICIPEG 2016 pp 45-59 | Cite as
Sensitivity Analysis of Sandstone Rock Elastic Properties to Effective Pressure Using a New Rock Physics Workflow and Its Application for Time-Lapse Seismic Data Analysis
Abstract
Sensitivity analysis of sandstone rock frame to pressure has been an appealing area of research in upstream oil and gas industry. Knowledge of the effects of various pressures on sandstone elastic properties has been used to interpret 3D seismic data and also to use time-lapse seismic data sets to monitor the dynamic changes in an oil and gas reservoir. Rock physics models build a relation between rock elastic properties and reservoir pressure; therefore, two rock physics approaches are used commonly to illustrate the dependency of rock elastic parameters to pressure. The first approach is empirical equations, and the second is to use contact theory models. Laboratory-derived empirical equations are used to relate rock elastic properties to pressure variations. Besides these equations, contact theory models also are used to investigate the sandstone rock elastic properties to pressure changes. The aim of this research is to present a new rock physics workflow to predict the effect of different pressures on dry sandstone rock elastic properties. Hertz–Mindlin contact theory in conjunction with the pore space stiffness theory is cooperated to model the pressure effects on dry rock seismic properties. This new rock physics workflow is calibrated with laboratory measurements on core samples. The results of the developed rock physics workflow show a perfect fit with the pressure laboratory measurements on core samples. Unlike other contact theory rock physics models, our workflow requires less time with a straightforward approach. An application of this rock physics workflow for time-lapse seismic feasibility modeling is also included in this research.
Keywords
4D seismic data Rock physics model Pressure sensitivity analysisNotes
Acknowledgements
The authors of this research papers want to express their deepest gratitude and thanks to PETRONAS for providing data and funding for this research. We are also so thankful of Universiti Technologi PETRONAS and University of Alberta, especially Tiewei He and Dr. Schmitt letting us to use the data and providing support for this research.
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