THE world counts on Saudi Aramco to deliver a reliable supply of petroleum.
Even though Saudi Arabia has sufficient reserves to produce oil at its current rate for many decades to come, it is constantly seeking to expand its reserves base. The company has achieved crude oil reserves replacement of 104 per cent, adding 3.6 billion barrels. In addition, it doubled its target for new non-associated gas reserves, adding 10.4 trillion cubic feet.
As technology has advanced and the understanding of petroleum geology and reservoir behavior has increased, projections of both oil in place and proven reserves have grown steadily, whether at the level of individual fields or global reserves.
Aramco has embarked upon an expanded exploration programme, designed to grow the kingdom’s proven reserves of oil and natural gas both onshore and offshore. With greater emphasis on increasing production of natural gas to fuel the domestic economy, its major discoveries recently were gas fields, the company says in its 2006 Annual Review.
It plans to drill more than 300 gas development wells and 230 exploration and delineation wells by 2011. In the next 10 years, the company hopes to add 50 trillion cubic feet (tcf) to its current 248.5 tcf of gas reserves.
In addition to three new gas fields the company discovered a new reservoir of non-associated gas in the Karan oil field, which was discovered in 1967.
Karan is now its largest offshore gas field. The Midrikah gas field, discovered in 2005, was completed in February 2006, flowing 30 million cu ft per day of gas with 900 bpd of condensate. Meanwhile, in the Rub Al-Khali, or Empty Quarter, Saudi Aramco’s four Upstream Gas Joint Ventures — South Rub’ Al Khali Company, Luksar Energy Limited, Sino Saudi Gas Limited and EniRepSa Gas Limited — reached a number of milestones.
All four companies met their seismic commitment programmes for the First Exploration Period, and at least three were considering additional seismic acquisition above their minimum commitment.
Preliminary drilling results have been encouraging. In support of the ongoing activities, two of the companies have set up seismic processing centres in kingdom. Aramco’s expanded exploration activities require massive investments in seismic acquisition and processing, and in reservoir characterisation.
The company has completed its two-year 3-D seismic survey of the Qatif field. The project covered about 653 square miles (1,692 sq km) of land, marine and transitional zone, which included towns, farms and the Ras Tanura Refinery and Terminal.
The project to acquire and process 3-D seismic data for the Khurais oil field that began in December 2004 was completed in September 2006. This was one of Aramco’s largest integrated programmes, covering more than 2,700 square miles (7,000 sq km) and 2.8 million recording profiles.
The final image volume covers the Khurais field and the neighbouring Abu Jifan field. Saudi Aramco geoscientists have developed a series of innovative technologies to estimate and subsequently remove unwanted multiple reflections from seismic data, which mask primary events indicative of oil and gas reservoirs.
These technologies have considerably reduced the risk associated with wildcat and developmental drilling and are expected to play a key role in processing seismic data from the Red Sea. Aramco is also conducting extensive integrated geological and simulation studies to optimise the new increments in Khurais, AFK (Abu Hadriyah, Fadhili and Khursaniyah), Manifa, Shaybah and Nuayyim.
The petroleum industry is witnessing tremendous advances in a wide range of technologies, including the massive computing power that supports numerous upstream applications. For example, the computing capacity at Saudi Aramco’s Exploration and Petroleum Engineering Center (Expec) has reached 34 teraflops, or 34 trillion floating point operations per second.
This represents a 300-fold increase in computing capacity since 1999, and indicates the exponential rate of development of upstream technology as a whole. The seismic processing environment in its Expec Computer Center (ECC) continues to grow.
The company has completed the largest disk installation and seismic data migration in the centre’s history. A total of 650 terabytes of new storage was installed for conventional seismic processing. Additional computer capacity was achieved through new and faster High Performance Computing clusters based on commodity PC hardware. The new seismic processing environment has increased computing capacity by 47 per cent and storage by 46 per cent.
Its computing capacity is helping it keep ahead of the curve in the crucial search for and characterisation of new reserves.
Aramco’s own Powers’ simulator employs refined multimillion cell models to optimise development of multilateral maximum reservoir contact (MRC) wells, equipped with “Intelligent Well” completions. Powerful parallel processors enable it to reduce computational time from a few days to a few hours.
The ECC designed and opened the Event Solution Centre, a state-of-the-art approach to reservoir studies wherein the collective skills of multi-disciplinary experts are focused on detailed uncertainty analyses and risk assessment processes. This approach, which compresses major decision cycles, reduces uncertainty and provides a wider range of alternatives, has yielded success in the Safaniyah and Manifa fields and is being applied in North ‘Uthmaniyah. Completion time for studies has been reduced from one to two years to one to three months. Given the scope of Aramco’s operations, it is no surprise that the company has more than 4 million engineering drawings representing the logical and physical design of its facilities.
Engineers e these drawings in performing daily operations at the plants, and quick access to accurate drawings is especially critical in responding to emergencies. Aramco has embarked on a corporatewide effort to implement “intelligent engineering drawings,” transforming its file-based graphical data into information stored in databases. This approach was adopted during the detailed design work on the AFK project, and will be deployed on the Khurais programme and the expansion projects at Shaybah and Hawiyah and Yanbu’ gas plants.
The company operates in very remote areas in the kingdom, and some of these remote operations are mobile, such as for exploration, drilling and marine activities. The communication needs for these activities can be met only with specialised satellite systems known as VSATs (Very Small Aperture Terminals). Aramco has ed this technology since 2001, but as its drilling schedule has accelerated, the need for greater highcapacity communications links has grown. To meet this need, the company has tripled the amount of bandwidth it leases, raising the total from 72 to 216 megahertz.
The new VSAT system provides robust communications to 300 remote sites and allows higher transmission speeds in support of powerful computing applications such as real-time well log data and remote monitoring of seismic activities.
In addition to its efforts to leverage technology above ground, Aramco is also utilising technologies below ground as it seeks to maximise ultimate recovery from its fields.
“We are widely recognised as an industry leader in using advanced technology throughout our upstream operations. Today, Intelligent Well technology, geosteering, MRC wells and the revolutionary i-Field or “Intelligent Field” concept are routinely applied in our new crude oil developments,” the company says.
A key indicator of the role improved technology can play in maximising production is that, for the seventh straight year, the company lowered the aggregate water-cut in its producing fields to an overall average of less than 25 per cent.
Recent advances in drilling technology are helping it meet its commitment to increased production – faster, better and at lower cost. For example, modification of the 18-5/8-inch casing point has enabled to drill a smaller 16-inch hole section in certain reservoirs with a better rate of penetration. Net savings are 15 days of rig time.
“We expanded the use of batch drilling to areas of higher geological uncertainty. Batch drilling involves drilling in succession the same hole section in each well on a given platform, rather than drilling each well individually. Once the same section is drilled in every well on the platform, then the next section is drilled on each well in succession. As each section is drilled, the rig crew learns the characteristics of that section from the first well and applies this knowledge when drilling the same section on subsequent wells,” the company says.
