Thermal Behavior Analysis of Geothermal Systems under the Influence of Rock-Formation Structures

Abstract

As part of the reservoir static characterization technique, behavior analyses of some of the obtained variables during the drilling and completion stages of wells of the Los Humeros Geothermal field (LHGF) are shown. It was used information obtained during both, the drilling and completion stages of the wells. The base information used data are those from thermodynamic measurements (temperature, pressure) and fluid circulation losses profiles. The determination of reservoir thermodynamic parameters initial conditions together with the analysis used at the completion stage allows identifying the thickness of the rock formation which in some cases be used for exploitation. The anisotropy of the rock formation shown through the heterogeneous behavior of the field wells is related to its volcanic environment and structures. Through the application of the analysis of thermodynamic behavior after well completion, were identified individual behavior profiles in each of them. However, after the selection of profiles with a similar trend, it was found that these, are related to location of each well. The particular behavior of some of the LHGF wells is used to identify compartments existence in the system which influences both, rock formation continuity at depth and geological structures that impact in fluid flow and its thermodynamic parameters. The found parameters during drilling wells are the technical sustain for taking decisions on its best completion depth. This information also is useful for selecting the thickness which must be exploited, in order to assure wells productivity. Through the different analyses applied in LHGF, besides obtaining reservoir static characterization can be identified that the geological structures influence its behavior.