Explosive Stimulation of Geothermal Wells

Abstract

The widespread, economic utilization of geothermal energy is at least partly dependent on efficient methods for stimulation of geothermal wells and formations. Well stimulation has become routine in the petroleum industry and yet, in spite of decades of downhole experience, most of the successful petroleum techniques cannot be used in a geothermal application. The principal problem is temperature, which imposes chemical, physical and mechanical limitations on equipment and stimulatio n fluids. The restrictions become particularly serious when formation temperatures exceed the 350' to 4OO0F range which of course are the better geothermal zones. ironically, one stimulation technique which has lost favor in oil and gas fields offers promise geothermally. Explosive fracturing, particularly bore shooting, can be used to fracture formations adjacent to the well bore.