Method of selecting a production well location in a hydrocarbon subsurface formation

A method for treating a tar sands formation, comprising:

• providing heat from one or more heaters to a hydrocarbon containing layer in the formation such that at least some hydrocarbons in the layer are mobilized;
• and
• producing at least some of the mobilized hydrocarbons through one or more production wells located in the hydrocarbon containing layer, wherein at least one of the production wells is located at a selected depth in the hydrocarbon containing layer so that hydrocarbons of a selected quality are produced from a part of the hydrocarbon containing layer.

A method for treating a tar sands formation, comprising:

• providing heat from one or more heaters to a hydrocarbon containing layer in the formation such that at least some hydrocarbons in the layer are mobilized;
• and
• producing at least some of the mobilized hydrocarbons through one or more production wells located in the hydrocarbon containing layer, wherein at least one of the production wells is located at a selected depth in the hydrocarbon containing layer so that hydrocarbons of a selected API gravity are produced from a part of the hydrocarbon containing layer.