MANAGED PRESSURE DRILLING

To properly use the Managed Pressure Drilling technique, a downhole valve, placed within the drillstring is highly beneficial. When combined with a rotating control device, drilling through thief zones and drilling while producing becomes possible. Using this combination of MPD techniques, authors from ConocoPhillips and Weatherford describe how they drilled extreme high-rate wells in an Indonesian gas field.

Using much of the same equipment, combined with computer control and a very sensitive flow meter for “micro-flux” control, authors from Chevron and Secure Drilling detail a new MPD method that was first used experimentally in 2006. This article tells how it has worked on the first 40,000 feet of wells drilled.

 HIGH PRESSURE/HIGH TEMPERATURE

Clear brine completions. Seven years of experience completing HPHT wells using cesium formate brines. Over 120 wells were studied to produce this paper. The results are discussed by authors from Statoil and Cabot Specialty Fluids.

 DEEPWATER

Downhole vibration mitigation for Chevron’s TD-record well in ultra-deepwater Walker Ridge field is accomplished using FEA-optimized drillstring and BHA analysis performed by Smith Technologies and the Smith Borehole Enlargement group. The optimization procedure involved static and dynamic modeling of the drillbit and BHA for each section of the St. Malo 3 well.

Completing extremely deep GOM wells for the Tahiti project presented a problem for setting sump packers. Chevron needed an alternative to tubing-conveyed hydrostatic packer setting. Another issue was that common explosive-type wireline setting tools have a hydrostatic pressure operational limit well less than Tahiti’s 20,000 psi BHP. This article by Halliburton and Chevron authors explains how these problems were overcome using a downhole power unit on a wireline, overcoming pressure and temperature constraints and saving significant rig time.

 DRILLING

Casing while drilling. Data from more than 250 wells drilled with casing while drilling technology provide extensive database for risk modeling and prediction. Authors from Fidelity Exploration & Production, Tesco and Turnkey E&P describe not only the benefits of casing while drilling, but statistically show what works in a particular application.

Friction and wear of hard-face claddings for deep-hole drilling. Authors from the University of Tennessee, Stoody and Oak Ridge National Laboratory describe the correlation between friction and wear of claddings and casings, and various factors effecting cladding wear. The article suggests that the selection of casing and cladding materials can affect sliding friction as much as slurry composition can.

The right fluid, hydraulics modeling and engineered sweeps make drilling and completing a difficult well possible. Authors from Mestena Operating and Halliburton tell how an engineering approach to lost circulation issues helped eliminate the need for a 7-in. intermediate string a well in Brooks County, Texas. Two offset wells with similar profiles had lost the battle to severe lost circulation in the Vicksburg sandstone, requiring the operator to routinely factor in $500,000 per well for intermediate casing.

 WELL LOGGING AND FORMATION EVALUATION

Latest advances in MWD and formation evaluation. This is our well-received, annual wrap-up of new technology in the areas of Logging While Drilling and Measuring While Drilling technology. The author is a former vice president of technology, and former editor of the SPWLA’s The Log Analyst.

Single-phase gas sampling. In vuggy formations in South Sumatra, reservoir pressure is typically just above dewpoint. This means that pressure must be maintained above dewpoint even with sampling operations. Using a new oval pad pump-out formation tester, with nitrogen gas charged sample bottles, good quality samples were obtained in these difficult fields, as told by authors from Halliburton and JOB Pertamina Hess.

 GEOLOGY/GEOPHYSICS

AVO has arguably been the one of the most useful techniques ever developed for looking at seismic data. There have been several ways to employ it. This article overviews the methods of Goodway, Shuey and Russell, among others, discusses the utility of each method for the appropriate situation, and gives examples.

Paleobiology as a driver in E&P activities. Two examples of enhanced exploration potential from the Dutch Upper Jurassic offshore Netherlands illustrate the point that this often overlooked science can be an essential tool for the explorationist. Authors from NTO-NITG discuss biostratigraphic techniques to identify stratigraphic sequences of the Upper Jurassic, a complicated non-marine-to-shallow-marine complex. Authors use newly identified sequences to explain, in two examples, the existence of only one economic oil field and the misplacement of exploration wells, showing the importance of paleo-environmental understanding for future exploration potential.

 RMOTC

More than two dozen new technologies are being developed to take advantage of the US’ new leasing program on federal lands containing oil shale. Several of these are making it to the pilot stage. The technology described here is a novel situ natural gas injection and extraction method for shale oil. The technology will be tested at the RMOTC testing center. It uses natural gas in a new, closed loop system to create the needed conditions for in situ conversion of oil shale into oil and oily products.