A coal formation may be treated using an in situ thermal process. A mixture of
hydrocarbons, H2, and/or other formation fluids may be produced from
the formation. Heat may be applied to the formation to raise a temperature of a
portion of the formation to a pyrolysis temperature. Pressure within the formation
may be controlled as a function of temperature or temperature within the formation
may be controlled as a function of pressure to yield a desired mixture.
