Method of rubbling a pillar

摘要: Shale oil is recovered from a subterranean formation containing shale by excavating to form at least one void, leaving zones of unfragmented above and below each void support pillar in the void. Explosive placed for explosively expanding zone toward The prepared explosive expansion drilling substantially horizontal blastholes loading charges into blastholes. Thereafter, are detonated single round explosions At then expanded fragmented permeable mass particles an situ retort. Gas introduced establishing retorting wherein retorted produce gaseous liquid products advancing through mass. Gaseous withdrawn