DRILLING AND COMPLETION TECHNOLOGY

How much is left of your centralizer after exiting a casing window in an extended-reach, horizontal multilateral? This mouthful of terminology relates to problems and solutions experienced by ConocoPhillips during its development of Alaska’s West Sak oil field with extended-reach multilateral wells. In these wells, horizontal slotted liners are utilized in conjunction with Level 3 multilateral junction systems. Accordingly, centralizers are required on the slotted liners. However, there were several failures of centralizers run through casing exits. Authors from ConocoPhillips and Baker Oil Tools describe how the problem was studied and solved with modeling and yard tests on various types of centralizers.

The effect of well trajectory on horizontal well performance. As horizontal wells get longer and more complicated, wellbore hydrodynamics becomes an issue with well performance. Elevation change in well trajectory can affect well performance, and when vertical permeability is much smaller than horizontal permeability, then an undulating wellbore may be favorable to overcome the low vertical permeability. Authors from Pioneer Natural Resources and Texas A&M University discuss how a simple analytical model is used to examine flow conditions for inclined or undulated horizontal wells, and how that model was then used to analyze the development plan for Alaska’s Cosmopolitan oil field.

In Alaska’s Alpine Field on the North Slope more than 600,000 feet of hole has been drilled in some 100 horizontal wells. Authors from ConocoPhillips Alaska Inc.; Halliburton Sperry Drilling Services, Halliburton Security DBS and Alaskan Energy Resources share how they increased drilling performance in the intermediate 8 ½-in. hole section by “matching” downhole tools and bits.

Just how far can extended reach go? Using the latest drill pipe improvements (titanium), coupled with friction reducers and mono-diameter well construction, ERD can go farther than ever imagined. This article describes the cutting edge of extended reach technologies.

Horizontal wells used in SAGD developments are typically completed with slotted liners to control sand. These devices are subject to many high installation and operational loads that can affect their performance. This article from an expert at C-FER Technologies presents several considerations for slotted liner design.

 PRODUCED WATER REPORT

DOE produced water information resource. A new Produced Water Management Information System developed by Argonne National Laboratory for the U.S. Department of Energy promises to benefit the oil and gas industry by offering easy access to unbiased information on produced water management options and regulations. The Website includes: 1) a technology description module providing fact sheets about currently employed PW management practices; 2) a regulatory module summarizing state and federal regulations; and 3) technology identification module that creates a decision tree identifying appropriate options based on user cues. The article describes the Website and explains how to use it.

 EXPLORATION

A new paradigm for explaining the origins of the Lower Tertiary in the Deepwater Gulf of Mexico. Recent commercial exploration success of over 60% in drilling the deepest wells in the deepest water point to a thick, regionally extensive sand body, The Whopper. How did it get there, over 200 miles from the nearest coastline of any age?

The concept of turning geophones into “virtual sources”� allowing them to be put almost anywhere, even below problem surfaces. Virtual sources can only be produced within the physical illumination bandwidth and the physical illumination aperture. To define them, all you need is the velocity model between the target and the virtual source, not between physical sources and receivers. They are particularly useful in 4D and problematic statics applications. An author from Shell explains the concept and uses.

 DRILLING, COMPLETION AND WORKOVER FLUIDS

World Oil’s exclusive annual reference comprises about 25 pages that show trade names, generic descriptions, recommended usage and suppliers of nearly 2,400 fluid systems/additives for drilling, completion and workover.