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Alaskan Update ALASKAN UPDATE ' ·, ''•·· ' ,~ fl' A Research Review Published by Member Companies of the Lease Planning and Research Committee Summer 1991 Volume 9, Number 2 ALBERTA TEST FACILITY DEMONSTRATES HEAVY OIL PRODUCTION FEASIBILITY Large deposits of bitumen, produced either by mining or naturally occurring asphalt, the surface, or drilling have been discovered in the horizontal wells into the Canadian province of Alberta. deeper formations (See Figure In fact, most of the one trillion 2, page 2). barrels of petroleum found in Alberta is contained in oil Surface Mining - Bitumen sands and heavy oil deposits. deposits found near the sur­ The largest of these deposits face are mined and the oil­ is in the Athabasca region saturated soils heated to li­ near Ft. McMurray (See quefy the oil and allow it to Figure 1, page 2). drain off. Once the mining At this time two commer­ activity is completed, the open­ cial projects are using surface pit mines are revegetated. mining techniques to produce oil. Ninety percent of the Horizontal Drilling - Deep estimated recoverable oil, During a March 1991 tour of AOSTRA facilities, LPRC member deposits are sometimes heated however, is buried too deeply company representatives examine the drilling rig which in situ (most commonly by for extraction by surface min- was modified to drill horizontal wells for the project. injecting high-presure steam ing. The Alberta Oil Sands into the bitumen) until the Technology and Research Authority Conventional Technology asphalt becomes fluid. The liquefied (AOSTRA) was created by the hydrocarbons are then produced Alberta government in 1974 to pro­ Until AOSTRA began testing using conventional oil well tech­ mote the development of new oil alternate production schemes, the nology. Both the injection and sands technology. Alberta oil sands deposits were Continued on page 2 U.S. Departntent of Energy Suntntarizes Arctic Data Development in the Arctic re­ computers (PC's). Its operational • a summary of the contents, quires that engineers have access to software and users' manual are con­ • the most efficient search a wide range of information from a tained on Compact Disk-Read-Only methodology, variety of sources. The information Memory (CD-ROM) media. • individual(s) to contact to obtain these engineers need includes The AORIS is made up of three the information, and history, culture, wildlife preserva­ components, the directory, the • the telephone number(s) of the tion, ice conditions, permafrost, soil bibliographic information system, contact(s). types, vegetation, etc. Recently, the and the scientific and engineering U. S. Department of Energy (DOE) information system. The com­ Information in the directory is developed a data base to provide ponents are linked to one another presented in a matrix which cross­ single-source bibliographic and so that the users may easily move references the sources of Arctic technical information which focuses from one component to another. information with major areas on the specific needs of offshore including energy development. Directory - The directory con­ • Arctic engineering, The DOE Arctic and Offshore tains a listing of 85 sources of • Geology and geophysics. Research Information System (AORIS) Arctic-related data. For each data • Geotechnical, .. runs on IBM-compatible personal base, the AORIS provides Continued on page 8 well drilling technology. Alberta Figure 1. A very large drilling rig Continued from page 1 ~lberta Test Facility Location was modified to handle a production wells are drill­ 12-foot diameter drill bit ed horizontally through and 10-foot diameter cas­ the hydrocarbon deposits ings. Conventional drill­ to increase the size of the ing muds were circulated production zone of each into the hole as drilling well (See Figure 2). The progressed to maintain cost of such wells is high. stability in the well bore. Further, the ''target The ten-foot casings were depth" (producing forma­ cemented into each shaft tion depth) for such wells to ensure hole stability must be fairly deep if and safe operations drillers are to achieve the throughout the life of the appropriate deviation of Ft. McMurray project. the well stem to complete a horizontal well. Drilling Rig - A custom drilling rig was designed to operate The "Missing" Zone - ALBERTA Between the deposits within the confined space near the surface and of the tunnel. Because those of sufficient depth the wells were drilled up­ to produce by directional ward and then diverted or horizontal drilling in a horizontal direction, techniques lies a "miss­ conventional top-down ing" zone. Researchers at drilling procedures were AOSTRA focused their not always applicable. attention on developing New techniques were technology for production developed for drilling from the "missing" zone. fluid pressure control, about a half mile of tunnels (12 feet well surveys, logging, and running The AOSTRA Facilities high by 15 feet wide) extends from casing under pressure. the shafts. From the tunnels, wells The AOSTRA Underground Test are drilled at a shallow upward Pilot Project Tests Facility (UTF) consists of twin ver­ angle into the oil bearing strata (See tical shafts about 10 feet in diameter Figure 3, page 3). Oil has been produced from the and over 600 feet deep. The shafts To accomplish their work, engineers AOSTRA facility utilizing a steam­ terminate in the limestone underly­ employed highly-specialized equip­ assisted gravity drainage (SAGD) ing the oil sands. A network of ment. process. As shown in Figure 4, a pair of horizontal wells is drilled Vertical Shafts - The mine shafts through the oil bearing formation. ALASKAN UPDATE were drilled using conventional oil- High pressure steam is injected to Published periodically by the member companies of the Lease Planning and Research Committee (LPRC) of the . , Figure 2. Alaska Oil and Gas Association (AOGA). Conventional, Bitumen ·Production Technology Member companies are: Amoco Production Company ARCO Alaska, Inc. BP Exploration, Inc. Conoco, Inc. ALBERTA Chevron U.S.A., Inc. TEST FACILITY • Elf Exploration Exxon Company, U.S.A. Marathon Oil Company Surface Mobil Exploration&: Producing U.S., Inc. Mining Zone Shell Western E&:P, Inc. UNOCAL ''Missing'' Address correspondence to: Sue A. Duthweiler, Editor ~ ~ Zone Alaskan Update clo Alaska Oil and Gas Association 121 West Fireweed Lane #207 Directional/ Anchorage, Alaska 99503 Horizontal Mailing list: Any individual or group may Drilling Zone write the address above to be put on the mail­ ing list free of charge. Back issues are also available at no charge. ®:> Oil Sands 2 Alaskan Update Figure 3. Figure 4. Underground ~ Test Facility Cross-Section of Producing Well ~\\\\\\\~\\\\\\\~ Top of Reservoir- Steam Injection Oil and Condensate are Drained Continuously \\\ \\\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \\ Source: A OSTRA Bottom of Reservoir Source: AOSTRA warm the heavy oil. Once the oil is has resulted in development of market circumstances change, this liquefied it flows downward into the technology that is more economical form of in situ recovery may production line. The oil and water than that previously available. As become commercially viable. (condensed from the injected steam) are then pumped to the sur­ face for processing. Completed wells stand Initial project wells extended into ready to produce the producing formation about 180 heavy oil at the Ft. feet from the tunnels. Because of McMurray AOSTRA encouraging well test results, site. AOSTRA plans on testing additional wells which will be completed to 1,800 feet in horizontal length. Under present market conditions, the technology described here is not economic. The research, however, LPRC In 1978, the Alaska Oil and Gas being considered or already • To promote, conduct, or take Association established the Lease adopted by various governmen­ part in studies and investiga­ Planning and Research Committee tal agencies which affect the tions consistent with the Com­ as a special committee to coordinate Alaska exploration, develop­ mittee's overall goals. the Association's activities relating ment, and production industry to both Federal and State lease sales Since the Committee was in Alaska. More familiarly known as • To consult with governmental established its members have par­ the LPRC, the Committee is made agencies on issues affecting the ticipated in more than 380 research up of businesses engaged in explor­ petroleum industry in Alaska. projects on such topics as regional ing for, producing, transporting, or environmental conditions, ice refining petroleum products. The • To prepare and coordinate thicknesses and movements, off­ current membership includes presentations for public shore drilling structures, oil spill Amoco, ARCO Alaska, BP Explora­ hearings. cleanup, marine transportation, tion, Chevron, Conoco, Elf Explora­ gravel and ice island construction, tion, Exxon, Marathon, Mobil, Shell, • To work with committees, aca­ oceanography, and engineering for and UNOCAL. demic organizations, and local frontier areas. Expenditures for communities, to exchange ideas these projects total more than $330 The Committee's goals are: and views on matters of mutual million (See Alaskan Update, interest and to support studies Volume 9, Number 1). Brief reports • To conduct a cooperative effort which may increase the ability on current LPRC projects appear to become familiar with and to of the industry to conduct petro­ regularly in the Alaskan Update. stay informed of the laws, rules, leum operations
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