| Abstract |
Large volume hydraulic injections into the Carnmenel is granite have been completed at the CSM Hot Iry Rock Project during the period October 1982 to July 1983, with small volume injection s before and after this period. The effects of the injection s on the hydraulic properties of the rock mass have been estimated by pressure transient analysis. The growth of the reservoir zone was tracked with microseismic locations, and the growth mechanism modelled with the computer program FRIP. The limited duration of the transients amenable to analysis and the tendency for growth below the injection zone meant that the inter - pretations could only describe hydraulic conditions within about 100 m of the wellbores. The effect of the large volume injections was to increase permeability values from less than 100 pd to greater than 5 md, and to decrease skin values from about -3 to about -6. The FRIP modelling explained the observed reservoir growth in plan with reference to measured in-situ stresses, jointing and rock properties and showed some of the limitations of continuum modelling. |