Pressure Buildup Monitoring of the Krafla Geothermal Field, Iceland

Abstract

A break in electrical power generation from the Krafla geothermal plant was planned from beginning o f May to early September 1984. Early in June most o f the production wells were shutin and their pressure recovery monitored. A regular monitoring o f the pressure buildup was carried out on a well to well basis until mid- August, when the wells were put back into production except for wells 12 and 16. They wera used to monitor the pressure drawdown due to the start of production. This was abruptly brought to an end by a nearby volcanic eruption in aarly September. The pressure buildup in the two-phase geothermal reservoir at Krafla is described and the first results presented. The results are compared with parameters determined on the completion of the wells and with predictions from numerical simulations of the reservoir. Finally the status o f the Krafla geothermal system is discussed with regard to the comparison.