# Estimating Oil Reservoir Permeability and Porosity from Two Interacting Wells

## Authors

• S. Sutawanir Statistics Research Division Institut Teknologi Bandung
• Agus Yodi Gunawan Industrial Financial Research Division, Institut Teknologi Bandung
• Nina Fitriyati Mathematics Department, UIN Syarif Hidayatullah
• Iskandar Fahmi Oil & Gas Drilling, Production & Management Research Division, Institut Teknologi Bandung
• Anggita Septiani Undergraduate student of Mathematics Study Program, Institut Teknologi Bandung
• Rini Marwati Universitas Pendidikan Indonesia

## Keywords:

ensemble Kalman filter, flow model, interacting well, sequential estimation, Laplace transform.

## Abstract

The Ensemble Kalman Filter (EnKF) can be used as a method to estimate reservoir parameters, such as permeability and porosity. These parameters play an important role in characterizing reservoir performance. The EnKF is a sequential estimation method that uses the parameters at t "? 1 (called prior) to estimate the parameters at t adjusted by observations at t (called posterior). In this paper, the EnKF was used to estimate the reservoir parameters for the case of a linear flow of two interacting production-injection oil wells. The Laplace transform was used to obtain an analytical solution of the diffusivity equation. A state space representation was generated using the analytical solution. A simulation study showed that the proposed method can be used successfully to estimate the reservoir parameters using well-pressure observations.

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