04254828 is referenced by 5 patents and cites 9 patents.

A method of producing fractures or gaps in geological formations of crystalline rocks in order to utilize the heat of the earth surrounding the gaps, comprises, drilling at least one bore into the rock, producing a pressure fluid in the bore adjacent the rock by introducing pressure gas-producing propellants into the bores to a location within the rock formation and reacting the pellants after they have been sealed off from the top of the bore and discharging the fluid pressure into the bore to put the rock under a pressure above its breaking limit so as to produce a large surface gap. The apparatus advantageously comprises a pressure gas generator which operates from a monergolic propellant which is decomposed catalytically and which includes a sealing bellows arranged around a reaction chamber at the bottom of the bore which is sealed at the upper end or to the rear and is connected with the pressure gas chamber and an outlet into the forming gap having a non-return valve therein.

Title
Apparatus for producing fractures and gaps in geological formations for utilizing the heat of the earth
Application Number
5/967839
Publication Number
4254828
Application Date
December 8, 1978
Publication Date
March 10, 1981
Inventor
German Munding
Bad Friedrichshall
DE
Armin Sowa
Ottobrunn
DE
Agent
McGlew and Tuttle
Assignee
Messerschmitt Bolkow Blohm
DE
IPC
E21B 43/26
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