NOVELTY - Hydrocarbon containing formation is treated in situ by using heat sources to heat portion of the hydrocarbon containing formation to temperatures that allow pyrolysis of the hydrocarbons.    USE - For in situ treatment of hydrocarbon containing formation, (e.g., formation containing coal, oil, shale and/or heavy hydrocarbons) for production of hydrocarbons, hydrogen, and/or other products e.g. fertilizer.    ADVANTAGE - The method yields high quality hydrocarbon products.    DETAILED DESCRIPTION - In situ treatment of hydrocarbon containing formation involves:    (i) providing heat from heat sources to at least a portion of the layer, where heat sources are positioned proximate to an edge of the layer;    (ii) allowing the heat to transfer from heat sources to a selected section of the layer so that superimposed heat from heat sources pyrolyzes hydrocarbons within the selected section of the formation; and    (iii) producing a mixture from the formation.    INDEPENDENT CLAIMS are included for the following:    (a) method of installing of wells in a hydrocarbon containing formation comprising forming a wellbore in the formation by geosteered drilling; and providing a heating mechanism within the wellbore so that the heating mechanism can transfer heat to at least a portion of the formation;    (b) system for heating hydrocarbon containing formation comprising a heater disposed in an opening in the formation; and a conduit for providing an oxidizing fluid from an oxidizing fluid to fluidize the hydrocarbons at the reaction zone during use so that heat is generated at the reaction zone;    (c) mixture produced from hydrocarbon containing formation comprising an olefin content of less than 10 wt.%; and an average carbon number less than 35; and    (d) method for in situ production of synthesis gas from a hydrocarbon containing formation comprising heating a section of the formation to a temperature to allow synthesis gas generation where a permeability of the section is uniform and greater than a permeability of an unheated section of the formation when the temperature to allow synthesis gas generation within the formation is achieved; providing a synthesis gas generating fluid to the section to generate synthesis gas; and removing synthesis gas from the formation.