Natural analogues are systems in nature, in which in historical or geological periods took place or recently are taking place physical and chemical processes similar to those, which can occur in an deep geological repository. Natural analogues represent excellent means, which enable the study of the ability of natural environment to halt and insulate radioactive material.

In natural reactors in Oklo (Gabon) about two billion years ago, as a result of fortunate aggregation of elements, spontaneous fission reaction took place, which lasted for about 500 thousand years. The same radionuclides originated as those originating in reactor of a nuclear power plant. Investigations in Oklo confirm an extraordinary capacity of local rock to halt radionuclides. Most of "radioactive waste" remained in the place of its origin or it moved away only minimally.

In Canada, under the Cigar Lake, in depth of 430 m in a crystallic rock under layer of loam, deposit of uranium ore occurs with uranium content up to 50 %, in form of uranium dioxide, similarly as in nuclear fuel. On the surface no sign is observable, which would provide indication about deposit's existence. System of engineering and geological barriers of deep repository is similar to geological barriers of this natural analogue.

Similarly to archaeological findings of glass and metal items dating from periods of more than several thousands of years ago demonstrating the speed of corrosion of containers and glass matrixes, examination of the copper cannon from the Swedish ship, the Kronan, which lay in the sediment in the Baltic Sea for 300 years, provided detailed information about the mechanisms of corrosion in a sedimentary environment. The results were used during assessment of the speed of corrosion of the Swedish and Finnish design of the container.