Page 54: of Offshore Engineer Magazine (May/Jun 2015)

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Drilling

Advances in technologies for additives and ? uids

Drilling in deeper waters calls

Gulf of Mexico ?eld discoveries for more advanced technology. 50

Mark R. Luyster provides an overview of recent ? uid 40 advances for the completion phase of deepwater projects.

30 he industry has evolved in the last decade to further drilling 20

T and completion ? uids that can attain the required density and integrity for deepwater Gulf of Mexico projects.

Annual reported discoveries

However, the desired parameters or 10 objectives for such systems breach the density and environmental limits, and challenge the industry to develop ? uid 0 systems that ultimately reduce the ’14 ’13 ’12 ’11 ’10 ’09 ’08 ’07 ’06 ’05 ’04 ’03 ’02 ’01 ’00 ’99 ’98 ’97 ’96 ’95 ’94 ’93 ’92 ’91 ’90

Year risk of failure. While proven technol- ogy reduces risk, the following article

Fig. 1 - Water depths greater than 4600ft. Source: BSEE.

includes a few potential advances with respect to the selection of the required the near recent discoveries will require 2003-2010 are now either advanced with ? uid systems and additives for these proven and new technology to develop respect to planning for ? rst oil or real- deepwater prospects, which will also and advance the infrastructure, drilling ized ? rst oil with one or more comple- require greater volumes during their and completion phases. These phases tions. Recent reports show more than 40 development phase. may well require technology that has prospects that may realize ? rst oil in the

Data from the US Bureau of Safety and not been devised, which contrasts with next few years. The maximum measured

Environmental Enforcement (BSEE) from proven technology that serves to reduce depth to attain the target reservoir for 1990 to present shows a relative increase risk. the appraisal and/or development wells in the number of discoveries between During the period between 2003-2010, approaches 32,000ft. These target reser- 1998-2002 (Fig. 1), approximately 32 the Gulf of Mexico realized exploration voirs range in age from lower Miocene per year while discoveries after 2002- drilling, appraisal and development in to Eocene-Paleocene to Upper Jurassic or 2010 range from 8-19 or 12 per year. water as deep as approximately 9575ft. approximately 33-65 million years to 160

BSEE’s data shows a marked decrease in Some of these prospects exhibited poten- million years for the latter. The reser- annual discoveries after 2010 (the year tial hydrocarbons/reserves estimated voir temperature for the Miocene can o

Deepwater Horizon happened), four per greater than 6 billion boe and operators exceed 200 F while the Eocene-Paleocene o year. However, BSEE’s data also shows a projected ? eld life up to 40 years. In the reservoirs can approach 250-270 F o marked increase for the water depth of last few years, some of these prospects and the Upper Jurassic over 300 F. The these discoveries nearly 1000ft for each are now realizing initial production uncompleted reservoir pressures for the of the aforementioned periods starting while several are pre-planning for their Miocene prospects may exceed 20,000psi with 1998-2002. If the same data is nor- development phase. One area of technol- while the Eocene-Paleocene can exceed malized for discoveries in water greater ogy that will play a role to successfully 22,000psi. Thus the equivalent density than 4600ft (Fig. 2) there is not only a complete these prospects is the required for these reservoirs range up to 14.5 relative increase as expected but all the ? uids and the additives and products lb/gal whereby a required drilling or discoveries for the period 2011-2013 are that are used to formulate these ? uids; completion ? uid approximates 15.5 lb/ 100% of this baseline as they represent also referred to as systems. Speci? cally gal. These reservoir parameters dictate a water depths from 5440-8553ft. It fol- the systems required to drill and com- need for drilling and completion ? uids lows that the subsequent appraisal and plete in the target reservoirs. (and their associated additives) with development wells from 2003-2010 and Several discoveries from the period relatively greater density and superior

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