| Abstract |
The Wairakei field has reached a mature stage of reservoir response, but new development has provided new data. We concentrate on data from new wells and one year of production fromthe western low pressure steam zone. The steam zone there is linked to the low pressure steam zone elsewhere, but the composition of the steam there prior to production reflected condensation and fluidrock interaction. The composition has now converged on that of the Western Borefield. The rate of change and the gas geothermometry show that steam is being provided by boiling from depth or from the east, rather than any substantial boiling of in-situ residual liquid. There is no evidence for a physical hydrological barrier on the western side of the field, nor is there evidence of cool water incursion due to pressure drawdown. The economic limit of the resource is smaller than the resistivity boundary. |