Modeling of Land Subsidence in the South Pars Gas Field (Iran)

Mohammad Hossein Taherynia, Seyed Mahmoud Fatemi Aghda, Akbar Ghazifard

Department of Geology, Faculty of Sciences, Kharazmi University, Tehran, Iran.
Department of Geology, Faculty of Sciences, University of Isfahan, Isfahan, Iran.

DOI: 10.4236/ijg.2013.47103                

Abstract

The objective of this study is to predict the subsidence of the South Pars gas field at the end of production period. With respect to the notable reservoir thickness, significant pressure drop due to extraction and high areal extent of the South Pars gas field there is a high subsidence potential in this field. In order to determinate the maximum land subsidence and subsidence profile of the South Pars gas field, at first, the reservoir compaction was estimated based on the thickness of the reservoir, the pressure drop in the reservoir and the uniaxial compaction coefficient of the reservoir rock, and then the effect of the reservoir compaction on the field surface was modeled with the use of analytical and semi-numerical methods. The compaction of the reservoir at the end of production period was estimated to be about 0.48 m. Both of the subsidence modeling methods show similar results and predict that the maximum subsidence will reach about 0.6 m at the end of production period.

Keywords

Subsidence; South Pars; Compressibility; Reservoir Rock; Analytical Method; Semi-Analytical Method

Conflicts of Interest

The authors declare no conflicts of interest.

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