Nonlinear-Parameter Estimation Based on History Matching of Temperature Measurements from Single-Phase Liquid-Water Geothermal Reservoirs

Abstract

In this study, the main objective is to investigate the use of temperature data through history matching for estimating the reservoir parameters related to fluid and heat flow. The investigation is conducted by using an analytical solution based on the modification of the analytical solution of Chekalyuk (1965) as a forward model to compute both transient pressure and temperature behaviors of a single-phase, liquid-water infinite-acting geothermal system. Our modification involves the incorporation of the skin factor into the original solution of Chekalyuk (1965) who did not consider the skin effects in temperature solution. Only, the constant-rate production tests were considered. Both the gradient based Levenberg-Marquardt and non-gradient Ensemble Kalman Filters (EnKF) have been considered as the non-linear parameter estimation methods. To simulate real cases, temperature data generated from the analytical solution were corrupted with normally distributed noise. The results show which of the reservoir parameters (e.g., skin, porosity, permeability, fluid and rock densities and heat capacities) can be reliably estimated from the sandface temperature transient data in the presence of noise, recorded during constant-rate drawdown tests. A comparison of the Levenberg-Marquardt and the EnKF in terms of estimation procedure and computational performance for the problem of interest is also provided.