The In-Situ Conversion Process (ICP) is the acceleration of natural maturation of kerogen "in place" (i.e. without mining).
ICP involves drilling heating wells into the oil shale with a smaller number of production wells strategically placed in the heating pattern. The heater wells gradually heat subsurface oil shale formation. The elevated temperature converts the kerogen into lighter hydrocarbons fractions, which are then brought to the surface through the production wells as light hydrocarbon fuel, leaving the coke residue in the reservoir.
The main features of ICP are: