Abstract: A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the tar sands formation from a plurality of heaters located in the formation. Heat is allowed to transfer from the heaters to at least a portion of the formation. A pressure in the portion of the formation is controlled such that the pressure remains below a fracture pressure of the formation overburden while allowing the portion of the formation to heat to a selected average temperature of at least about 280° C. and at most about 300° C. The pressure in the portion of the formation is reduced to a selected pressure after the portion of the formation reaches the selected average temperature.

Abstract: Systems and methods used in treating a subsurface formation are described herein. Some embodiments also generally relate to barriers and/or methods to seal barriers. A method used to treat a subsurface formation may include heating a portion of a formation adjacent to a plurality of wellbores to raise a temperature of the formation adjacent to the wellbores above a mobilization temperature of bitumen and below a pyrolysis temperature of hydrocarbons in the formation; and allowing the bitumen to move outwards from the wellbores towards a portion of the formation comprising water cooler than the mobilization temperature of the bitumen so that the bitumen solidifies in the formation to form a barrier.

Abstract: Systems and methods for treating a subsurface formation are described herein. Some method include providing heat to a section of the formation from a plurality of heaters located in the formation, allowing the heat to transfer from the heaters to heat a portion of the section to a selected temperature to generate an in situ deasphalting fluid in the section, contacting at least a portion of the in situ deasphalting fluid with hydrocarbons in the section to remove at least some asphaltenes from the hydrocarbons in the section, and producing at least a portion of the deasphalted hydrocarbons from the formation. The in situ deasphalting fluid may include hydrocarbons having a boiling range distribution between 35° C. and 260° C. at 0.101 MPa. A majority of the hydrocarbons in the section may have a boiling point greater than 260° C. at 0.101 MPa.

Abstract: Systems and methods for treating a subsurface formation are described herein. Some method include providing heat to a section of the formation from a plurality of heaters located in the formation, allowing the heat to transfer from the heaters to heat a portion of the section to a selected temperature to generate an in situ deasphalting fluid in the section, contacting at least a portion of the in situ deasphalting fluid with hydrocarbons in the section to remove at least some asphaltenes from the hydrocarbons in the section, and producing at least a portion of the deasphalted hydrocarbons from the formation. The in situ deasphalting fluid may include hydrocarbons having a boiling range distribution between 35° C. and 260° C. at 0.101 MPa. A majority of the hydrocarbons in the section may have a boiling point greater than 260° C. at 0.101 MPa.

Abstract: Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons including mobilized hydrocarbons are produced from the portion.

Abstract: Systems and methods for treating a subsurface formation are described herein. Some method include providing heat to a section of the formation from a plurality of heaters located in the formation, allowing the heat to transfer from the heaters to heat a portion of the section to a selected temperature to generate an in situ deasphalting fluid in the section, contacting at least a portion of the in situ deasphalting fluid with hydrocarbons in the section to remove at least some asphaltenes from the hydrocarbons in the section, and producing at least a portion of the deasphalted hydrocarbons from the formation. The in situ deasphalting fluid may include hydrocarbons having a boiling range distribution between 35° C. and 260° C. at 0.101 MPa. A majority of the hydrocarbons in the section may have a boiling point greater than 260° C. at 0.101 MPa.

Abstract: Systems and methods for treating a subsurface formation are described herein. Some method include providing heat to a section of the formation from a plurality of heaters located in the formation, allowing the heat to transfer from the heaters to heat a portion of the section to a selected temperature to generate an in situ deasphalting fluid in the section, contacting at least a portion of the in situ deasphalting fluid with hydrocarbons in the section to remove at least some asphaltenes from the hydrocarbons in the section, and producing at least a portion of the deasphalted hydrocarbons from the formation. The in situ deasphalting fluid may include hydrocarbons having a boiling range distribution between 35° C. and 260° C. at 0.101 MPa. A majority of the hydrocarbons in the section may have a boiling point greater than 260° C. at 0.101 MPa.

Abstract: Systems and methods used in treating a subsurface formation are described herein. Some embodiments also generally relate to barriers and/or methods to seal barriers. A method used to treat a subsurface formation may include heating a portion of a formation adjacent to a plurality of wellbores to raise a temperature of the formation adjacent to the wellbores above a mobilization temperature of bitumen and below a pyrolysis temperature of hydrocarbons in the formation; and allowing the bitumen to move outwards from the wellbores towards a portion of the formation comprising water cooler than the mobilization temperature of the bitumen so that the bitumen solidifies in the formation to form a barrier.

Abstract: Methods and systems for treating a hydrocarbon containing formation described herein include providing heat to a first portion of the formation from a plurality of heaters in the first portion, producing produced through one or more production wells in a second portion of the formation, reducing or turning off heat provided to the first portion after a selected time, providing an oxidizing fluid through one or more of the heater wells in the first portion, providing heat to the first portion and the second portion through oxidation of at least some hydrocarbons in the first portion, and producing fluids through at least one of the production wells in the second portion. The produced fluids may include at least some oxidized hydrocarbons produced in the first portion.

Abstract: Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons including mobilized hydrocarbons are produced from the portion.

Abstract: Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons are produced from the portion.

Abstract: Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. A pressure in the majority of the section may be maintained below a fracture pressure of the formation. The pressure in the majority of the section may be reduced to a selected pressure after the average temperature reaches a temperature that is above 240° C. and is at or below pyrolysis temperatures of hydrocarbons in the section. At least some hydrocarbon fluids may be produced from the formation.

Abstract: A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the tar sands formation from a plurality of heaters located in the formation. Heat is allowed to transfer from the heaters to at least a portion of the formation. A pressure in the portion of the formation is controlled such that the pressure remains below a fracture pressure of the formation overburden while allowing the portion of the formation to heat to a selected average temperature of at least about 280° C. and at most about 300° C. The pressure in the portion of the formation is reduced to a selected pressure after the portion of the formation reaches the selected average temperature.

Abstract: Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat may be controlled so that at least a majority of the section reaches an average temperature of between 200° C. and 240° C., which results in visbreaking of at least some hydrocarbons in the section. At least some visbroken hydrocarbon fluids may be produced from the formation.

Abstract: Methods and systems for treating a hydrocarbon containing formation described herein include providing heat to a first portion of the formation from a plurality of heaters in the first portion, producing produced through one or more production wells in a second portion of the formation, reducing or turning off heat provided to the first portion after a selected time, providing an oxidizing fluid through one or more of the heater wells in the first portion, providing heat to the first portion and the second portion through oxidation of at least some hydrocarbons in the first portion, and producing fluids through at least one of the production wells in the second portion. The produced fluids may include at least some oxidized hydrocarbons produced in the first portion.

Abstract: Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat may be controlled so that at least a majority of the section reaches an average temperature of between 200° C. and 240° C., which results in visbreaking of at least some hydrocarbons in the section. At least some visbroken hydrocarbon fluids may be produced from the formation.

Abstract: Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. A pressure in the majority of the section may be maintained below a fracture pressure of the formation. The pressure in the majority of the section may be reduced to a selected pressure after the average temperature reaches a temperature that is above 240° C. and is at or below pyrolysis temperatures of hydrocarbons in the section. At least some hydrocarbon fluids may be produced from the formation.

Abstract: Methods for treating a tar sands formation are described herein. Methods for treating a tar sands may include heating a portion of a hydrocarbon layer in the formation from one or more heaters located in the portion. The heat may be controlled to increase the permeability of at least part of the portion to create an injection zone in the portion with an average permeability sufficient to allow injection of a fluid through the injection zone. A drive fluid and/or an oxidizing fluid may be provided into the injection zone. At least some hydrocarbons are produced from the portion.