Numerical Investigations into the Formation of a 'High Temperature Reservoir'

Abstract

This paper summarizes an ongoing numerical modeling effort aimed at describing some of the thermodynamic conditions observed in vapor-dominated reservoirs, including the formation of a high temperature reservoir (HTR) beneath the "typical" reservoir. The modeled system begins as a hot water geothermal reservoir, and evolves through time into a vapor-dominated reservoir with a HTR at depth. This approach taken here to develop a vapor-dominated system is similar to that of Pruess (1985), and involves induced boiling through venting. The reservoir description is intentionally generic, but serves to describe a means of evolution of conditions observed (in particular) at The Geysers.