The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 10, 1984
Filed:
Mar. 25, 1983
Thomas E Ricketts, Grand Junction, CO (US);
Occidental Oil Shale, Inc., Grand Junction, CO (US);
Abstract
There is provided a method for forming an in situ retort containing a fragmented permeable mass of formation particles in a retort site within a subterranean formation. A void is excavated into the formation and a zone of unfragmented formation is left adjacent the void. A plurality of explosive charges are formed in the zone of unfragmented formation. At least one central explosive charge is in a central portion of the zone of unfragmented formation, and a plurality of outer explosive charges are in the zone of unfragmented formation nearer the side walls of the void than the central explosive charge. The distance from each such outer explosive charge to an adjacent side wall of the void is about equal to the crater radius of the outer explosive charge. The central and outer explosive charges are detonated for explosively expanding the zone of unfragmented formation toward the void for forming a fragmented permeable mass of formation particles in the in situ retort. The retort has a horizontal cross-sectional area at an intermediate elevation which is less than the horizontal cross-sectional area of the retort at elevations above and below the intermediate elevation.