In Asia, two projects moving forward in extreme climates represent some of the coldest frontiers for exploration and production, and preparing for ice impact is a big feature for bo

Technology and innovation enable operators to pursue hydrocarbons in the world's most inhospitable locations, such as Kashagan field in the northern Caspian Sea.

In the northern Caspian Sea, Agip KCO, operator of what was the Offshore Kazakhstan International Operating Co. (OKIOC), is appraising the 20 billion- to 50 billion-bbl Kashagan field.
And off Russia's east coast, the ExxonMobil-operated Sakhalin 1 project reached a major milestone with a declaration of commerciality for the development.
For both projects, ice-bound operating conditions will be a challenge during the winter months.
For Kashagan, Deutag KCA is supplying one of two rigs appraising the field.
This unit has begun a fifth appraisal well, operating from an artificial island. Abbot Group of Aberdeen, Scotland, which owns KCA, is using KCA-Deutag's 3,000-hp T47 land rig, which previously saw service on BP's Wytch Farm project in southern England for extensive stepout drilling from shore, drilling up to 35,000 ft (10,700 m). The T47 is expected to remain in the north Caspian Sea for the next 5 years, doing development drilling on Kashagan.
The rig's ancillary drilling equipment underwent a substantial upgrade to cope with north Caspian winter conditions, where the mercury can dip below -5°F (-20°C) and summer temperatures can easily reach 103°F (40°C). Strong tidal currents and fluctuating sea levels also are part of the operating environment.
Fire and gas detection equipment and mud processing systems are kept in heated tents at the drilling site, and the facility has tracked Arktos ice escape vehicles and a waste treatment plant to keep the environment clean.
Drilling operations are carried out from an artificial island and may well represent the way in which Kashagan could be developed.
An ice-breaking ship towed equipment to the site, allowing 120 contractors and operating staff to live in relative comfort despite the remote and hostile environment.
Because of the shallow water depth - 7 ft to 30 ft (2 m to 10 m) - ice formed on the sea surface during the winter is easily forced by wind action into large piles. It is these ice piles that present a major physical hazard for the drill site. "One of the features of the island is its sloping sides, which are designed to push the ice upwards to generate ice rubble rather than allowing it to move across the island," said Ian Lane, KCA's operations director responsible for Kashagan.
Kashagan history
Testing on the giant field, discovered in 2000, began with the Kashagan East 1 well. Kashagan West 1 was spudded with a Sunkar rig Oct. 6, 2000, and completed to a 16,340-ft (4,982-m) TD. It encountered an oil-bearing Paleozoic Carbonate interval below 13,940 ft (4,250 m), which tested at 3,400 b/d of 42° to 45° API oil and 7.6 MMcf/d of gas in May 2001. The Sunkar is a converted swamp barge, and at 6,000 tonnes is claimed to be the largest in the world. Modified for Caspian operations, it features two 13-ft (4-m) -high tanks on each side to provide ice protection. It measures 278 ft by 174 ft (85 m by 53 m) and stands nearly 128 ft (5.5 m) high.
Based on data from West 1 production tests, operator Agip has suggested Kashagan wells could produce between 5,000 b/d and 20,000 b/d of oil.
The West 1 well was drilled 25 miles (40 km) west of East 1 and encountered the same reservoir. The second well on the field, West 1 is 47 miles (75 km) southeast of Atyrau in the northeast Caspian.
Kashagan East 2, the field's third well, began in May 2001, and was drilled by Parker Drilling's Rig 257 on the Sunkar unit to a depth of 13,585 ft (4,142 m), 5 miles (8 km) from the Kashagan East 1 appraisal. Good porosity, high permeability and a flow rate of 7,400 b/d of oil were detected following a logging and test program. The same unit is continuing appraisal of Kashagan East.
Following a declaration of commerciality, producible resources from the field were estimated at between 7 billion and 9 billion bbl of oil.
Control of Kashagan passed to Eni/Agip in August 2001 with the change of name from OKIOC to Agip KCO (Agip Kazakhstan North Caspian Operating), which operates the field for the seven-member international consortium comprising BG, Eni, ExxonMobil, Inpex, Phillips, Shell and TotalFinaElf.
Since 1977, Agip has worked with Halliburton Energy Services on technology for drilling Kashagan wells. Earlier this year the Italian group extended its integrated drilling services agreement with the contractor for another 2 years in a deal worth US $120 million to continue providing support for the field's appraisal program. Halliburton will provide well construction and data acquisition services as part of the drilling services contract. Waste treatment is an important part of the deal too, since the operator is obliged to ensure that the sensitive north Caspian ecology is left unharmed by the appraisal operations, regardless of the winter and summer temperatures.
Another challenge imposed by the environment is the requirement to protect flora and fauna. The north Caspian Sea is home to a substantial sturgeon population, so spillage must be carefully avoided.
On the drilling front, Halliburton will continue to provide advice and solutions for the deep wells, which are encountering unstable salt, high pressures and high levels of hydrogen sulfide gas, along with the potential for high losses of drilling mud.
Concrete island
Like Kashagan, Sakhalin I also must overcome an ice-bound environment.
Operator ExxonMobil is relying on a concrete island to provide a drilling platform for its operations there. Exxon first used the Orlan in 1984 to drill in the Beaufort Sea off Alaska's North Slope.
Orlan features a steel mud base, a concrete midsection and two steel decks. It was engineered for year-round operations in Arctic conditions.
Earlier this year a Russian company was selected to upgrade the Orlan. Exxon Neftegas (ENL) awarded a $140 million fixed-price contract in May to Amur Shipbuilding Plant (ASP) in Komsomol'sk-na-Amur in Russia's far east to refurbish the Orlan facility. The contract covered engineering, procurement, construction and platform installation work.
Neil Duffin, ENL president, said awarding this contract to a Russian company was proof of the Sakhalin group's desire to maximize Russian content for phase one. "We are pleased this contract has been awarded to a Russian company that is well qualified for this type of work," he said. "We will continue to seek Russian expertise and integrate our collective skills and experience to address the many challenges involved in this project."
Upgrading the Orlan began in June after a tow in 2001 from Alaska's Bering Sea to the Russian port of Sov Gavan, and the platform is due for installation in 2004. ASP was founded in the 1930s - two decades after the Russian revolution - and has built military and commercial vessels.
More recently it constructed foundations and topsides modules for other Russian far east projects, and ASP's contract takes the value of awards to Russian suppliers for Sakhalin I up to $530 million since 1996.
"It is a large structure that can survive the ice floes," said ExxonMobil's Tom Hall, Sakhalin I project manager.
Orlan takes its name from a white-shouldered sea eagle, said to symbolize strength, boldness and speed and indigenous to Sakhalin Island.
Three offshore fields in the Sea of Okhotsk - Chayvo, Odoptu and Arkutun-Dagi - are due to be tapped in four phases as part of Sakhalin I. First oil is due late 2005, with 250,000 b/d of oil anticipated at peak from Chayvo.
Up to 55 wells are planned for Sakhalin, with horizontal stepouts of between 20,000 ft and 36,000 ft (6,097 m and 10,975 m).
Once the Orlan upgrade is complete for phase one, it is due to be installed 7 miles (11 km) offshore in 50-ft (15-m) waters. Twenty wells will be drilled from the platform. Another nine wells will be drilled into the northwest flank of Chayvo and Odoptu from an onshore facility for phase one. In March Parker Drilling landed a deal with the Sakhalin 1 operator to construct and operate a new land rig for the onshore drilling site at Sakhalin Island, due to be completed by now.
Robert L. Parker Jr., president and chief executive officer of Parker Drilling, said, "The new Sakhalin rig, engineered exclusively for this project, will be the most sophisticated land drilling rig in the world, designed to withstand earthquakes and operate in the frigid winters where ice covers the Sea of Okhotsk for 6 months of the year."
Ice-breaking support
vessels will provide year-round supplies for the drilling operations.
Like Kashagan, Sakhalin is a shallowwater project with big reserves; 2.5 billion bbl of oil and 17 Tcf of gas are estimated for Sakhalin, with investment projected at up to $3.7 billion. It represents the largest direct foreign investment project in Russia.
"Industry-leading arctic technology is being utilized to better define ice, wave and seismic loads and enable the design of safe, cost-effective producing systems for fields offshore Sakhalin Island," ExxonMobil said. "An understanding of arctic technology fundamentals is also the key to designing pipelines carrying fluids to and from onshore processing facilities."
Winter weather in the region brings severe storm conditions, and ice floes are a hazard all the way down the eastern coastline of the island as far as Japan. Furthermore, the region is known for seismic activity. Here, ExxonMobil will have to employ expertise gained from other seismically active areas.
Additionally, a gas export pipeline is planed from north Sakhalin south to Tokyo, Japan. In May 1999 Exxon Japan Pipeline agreed with Japan Sakhalin Pipeline FS Co. - owned by Japan Petroleum Exploration, Itochu Corp. and Marubeni Corp. - to investigate the feasibility of a gas pipeline from the Russian Sakhalin border to Japan, using Chayvo gas for supplies. While ExxonMobil is pursuing gas exports sales, efforts are under way to develop a framework for commercial gas supplies from the area to Russia's domestic market.

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