A method for treating kerogen in a subterranean zone which includes the use of supercritical carbon dioxide or emulsions of liquid carbon dioxide and an aqueous fluid. The carbon dioxide or emulsions can further include oxidizers. The oxidizers can include inorganic oxidizers or organic oxidizers, for example an oxidizer including an organic cation and an oxidizing anion. Additional additives such as polymers, crosslinkers, clay inhibitors, scale inhibitors and corrosion inhibitors can further enhance the efficiency of the kerogen-treating carbon dioxide or emulsion.