Hydraulic fracturing initiation and propagation in deep inclined open hole for Enhanced Geothermal System

Abstract

This paper describes the development of a generic geomechanical model for estimating the fracture initiation in open hole section and the overall fracturing propagation during the hydraulic stimulation in Enhanced Geothermal System. General studies on the effects in situ stress and open hole trajectory on hydraulic fracturing indicate that 1) the upward growth of vertical fracture is expected for normal faulting and strike slip stress regimes; 2) the fracture initiation at casing shoe section prevails for common stress range at deep formation; 3) an inclined open hole tends to decrease fracture pressure gradient for normal faulting and reverse faulting stress regimes and 4) an open hole with building up trajectory may shift fracture initiation location from casing shoe to well toe by a lower breakdown pressure. The proposed model predicts fracture initiation at well toe location for Jolokia-1 stimulation by NaBr brine.