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:
Sep. 11, 1979
Filed:
Dec. 29, 1977
Richard D Ridley, Bakersfield, CA (US);
Occidental Oil Shale, Inc., Grand Junction, CO (US);
Abstract
An in situ oil shale retort is formed in a subterranean formation containing oil shale. The formation comprises at least one stratum of relatively higher average kerogen content which is included in formation of relatively lower average kerogen content. A void is excavated in a retort site in the formation, leaving a remaining portion of unfragmented formation within the retort site adjacent the void. The portion of unfragmented formation within the retort site is explosively expanded toward the void to form a fragmented permeable mass of formation particles containing oil shale in an in situ retort in which fragmented formation particles from the stratum of higher kerogen content have a larger void fraction than the averge void fraction of the fragmented mass. This can be accomplished by enlarging the void in the vicinity of the stratum having the higher kerogen content prior to explosive expansion. When the fragmented mass is retorted, there is no substantial increase in resistance to flow of gas through the fragmented mass due to the relatively higher thermal expansion of fragmented formation particles having the higher kerogen content.