A method for forming an in situ oil shale retort in a subterranean formation containing oil shale is provided. The in situ oil shale retort has a top boundary, generally vertically extending side boundaries, and a bottom boundary of unfragmented formation. A first portion of formation is excavated for...http://www.google.es/patents/US4360233?utm_source=gb-gplus-sharePatente US4360233 - Method of bulking an in situ oil shale retort substantially full of fragmented shale
Method of bulking an in situ oil shale retort substantially full of ...
