Fracture Acidization Study of Calcareous Siltstone from a Geothermal Reservoir

Wolgemuth, K.M. ; Abou-Sayed, A.S. ; Ahmed, U. ; Schatz, J.F. ; Jones, A.H.
Paper presented at Geothermal Resource Council; Vol/Issue: 4; Geothermal Resource Council annual meeting; 9 Sep 1980; Salt Lake City, UT

Abstract

Laboratory tests have been performed to evaluate the effects of hydrochloric and acetic acids on fracture conductivity at in situ conditions. This work was done on core samples of calcereous silstone from the Salt Lake Formation (the injection horizon) at the Raft River geothermal area to assess whether an acid hydraulic fracture would improve injectivity. Acid treatment resulted in reduced fracture conductivity caused by partial dissolution of the calcite matrix and the subsequent closure of the fracture.