03986557 is referenced by 220 patents and cites 7 patents.

A method of producing bitumen from a subterranean tar sand formation characterized by the following muti-step process. First, a continuous wellbore having a second section thereof contained within the formation and a first and a third section extending said second section to the earth's surface is formed. Next, a perforated liner is inserted into the wellbore extending the entire length thereof and having perforations so positioned thereon to be adjacent the second section of the wellbore. Thereafter, a heated fluid is circulated through the wellbore, contacting the formation via the perforations, thereby reducing the viscosity of the bitumen contained therein rendering it mobile. Subsequently, the mobilized bitumen is recovered via the wellbore.

Title
Production of bitumen from tar sands
Application Number
5/584517
Publication Number
3986557
Application Date
June 6, 1975
Publication Date
October 19, 1976
Inventor
Eddie Paul Howell
Plano
TX, US
John Howard Striegler
Richardson
TX, US
Agent
Ronnie D Wilson
Assignee
Atlantic Richfield Company
CA, US
IPC
E21B 43/24
E21B 7/04
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