In an embodiment, a method of treating a kerogen and liquid hydrocarbon containing
formation in situ may include providing heat from one or more heat sources to at
least a portion of the formation. Heat may be allowed to transfer from the one
or more heat sources to a part of the formation. In some embodiments, at least
a portion of liquid hydrocarbons in the part may be mobilized. At least a portion
of kerogen in the part may be pyrolyzed. In certain embodiments, a pressure within
at least a part of the formation may be controlled. The pressure may be controlled
to be at least about 2.0 bars absolute. A mixture may be produced from the formation.