A Summary of Recent Study on the Initial State of the Matsukawa Geothermal Reservoir

Abstract

Feed point pressures of some of the earliest production wells i n Matsukawa were reconstructed from water levels and temperature profiles measured during warm up of the wells immediately after drilling . Although most of the wells currently produce dry superheated steam, the reconstructed pressures indicate that the pressure gradient of the production zone was super-hydrostatic and was similar to that of Kakkonda. which is a liquid-dominated system. It implies that the current production zone of the Matsukawa reservoir was induced to produce dry superheated steam mainly by little water recharge and high heat flow.