A hydrocarbon containing 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. Heat may be supplied
to the formation by reacting an oxidant with hydrocarbons adjacent to heater wellbores
to generate heat. Generated heat may be transferred to the portion substantially
by conduction to pyrolyze at least a portion of hydrocarbon material within the portion.
