In an embodiment, a method for heating a hydrocarbon containing formation
may include providing heat from one or more heaters to an opening in the
formation. A first end of the opening may contact the earth's surface at
a first location and a second end of the opening may contact the earth's
surface at a second location. The heat may be allowed to transfer from
the opening to at least a part of the formation. The transferred heat may
pyrolyze at least some hydrocarbons in the formation. In certain
embodiments, providing the heat to the opening may include providing
heat, heated materials, and/or oxidation products from at least one
heater to the opening.