ARMA 12-408 Characterization of two shallow aquifers for produced water injection

摘要

The Statfjord field is an old field that has now entered its late life phase where the current strategy is deep depressurization to produce solution gas. The large amounts of water produced were initially planned to be disposed through injection in overlying shallow aquifer reservoirs. In order to be able to optimize sustainable injection design, two well tests were performed with long fall-offs. The main parameters determined are the reservoir connectivity, minimum stress, flow capacity and pore volume compressibility. This article presents the results of these well tests and to increase the confidence of our interpretation, we compare them with results from other wells and independent testing methods. We discuss the ambiguity and uncertainties of our interpretation. As a general conclusion we demonstrate that it is challenging to properly characterize shallow reservoirs. This article contributes to an oil industry workflow leading to a better understanding of the design of large scale shallow reservoir injection schemes.