Producing shale oil by flowing hot aqueous fluid along vertically varied paths within leached oil shale

Claim 1

A process for producing oil from a subterranean oil shale deposit which comprises opening at least two wells into a relatively permeable leached zone within a soluble mineral-containing subterranean deposit of oil shale; initially injecting steam into a lower portion of the leached zone around at least one well while producing fluid from a lower portion of the leached zone around at least one other well; when plugging near an initial producing location becomes at least imminent, initiating fluid production substantially vertically above that location; terminating fluid production from the initial production location; injecting hot aqueous fluid into the initial fluid production location in a volume sufficient to at least significantly increase the effective permeability to the fluid being injected; and recovering shale oil from fluid produced from the leached zone.