US 4,223,734 A · Process of breaking and rendering permeable a subterranean rock mass

Abstract

The process of the present invention involves the following steps: producing, as by hydrofracing, a substantially horizontal fracture in the subterranean rock mass to be processed; emplacing an explosive charge in the mass in spaced juxtaposed position to the fracture; enlarging the fracture to create a void space thereat, an initial lifting of the overburden, and to provide a free face juxtaposed to and arranged to cooperate with the emplaced explosive charge; and exploding the charge against the free face for fragmenting the rock and to distribute the space, thus providing fractured, pervious, rubble-ized rock in an enclosed subterranean chamber. Firing of the charge provides a further lifting of the overburden, an enlargement of the chamber and a larger void space to distribute throughout the rubble-ized rock within the chamber. In some forms of the invention an explosive charge is used to produce a transitory enlargement of the fracture, and the juxtaposed emplaced charge is fired during the critical period of enlargement of the fracture.

Claims10

Dependent claims

The process for breaking and rendering permeable a subterranean mass of rock comprising:

hydrofracing substantially vertically superimposed substantially horizontally extending fractures in said mass delineating rock to be fragmented;
pumping of a liquid explosive into one of said fractures;
firing an explosive in the other of said fractures to produce a transitory enlargement thereof and to provide a free face;
and
firing said liquid explosive during the period of said enlargement.

2 more elements

The process of creating a fracture in a subterranean rock mass comprising:

boring a plurality of substantially vertical holes from the surface into said mass, said holes being arranged in a pattern having a center hole and a plurality of outer holes circumferentially positioned around said center hole;
hydrofracing from said center hole to produce a fracture driven outwardly therefrom to intersect said outer holes;
injecting hydrofracing fluid through said outer holes into said fracture, thereby extending said fracture laterally and producing an enlargement thereof;
emplacing explosive charges in said holes in spaced confronting relation to said fracture;
firing an explosive in said fracture to produce a transitory enlargement thereof and a free face confronting said charges;
and
exploding said charges during the period of said enlargement.

4 more elements

Dependencies are inferred from the claim text.

Process of breaking and rendering permeable a subterranean rock mass

Life of this patent

Process of breaking and rendering permeable a subterranean rock mass

Life of this patent

Abstract

Claims10