The Adar oilfield, also known as the Adar Yale, Adar Yeil or Adaril field, is an oilfield situated in the Melut in South Sudan estimated to contain about of oil. The Chevron Corporation discovered the Adar Yale field in 1981, shortly before the start of the Second Sudanese Civil War (1983–2005). Soon after Chevron had suspended operations in 1984, Sudanese government troops began attacking civilian settlements in the area, burning the houses and driving the people away, and in the late 1990s, Nuer militias from Nasir helped the army in clearing away the people to make way for the roads and infrastructure of the oilfield.
President Omar al-Bashir inaugurated the site in March 1997, and it initially produced just a day. Production from this oilfield, which lies close to the borders with Sudan and Ethiopia, has the potential to bring significant economic benefits to the region. However, until recently the focus has been on clearing the population away from the oilfield rather than on a longer term strategy for developing the region. China has provided a large investment in the Adar oilfield and others in South Sudan and Sudan and has made plans to make extensive further investments.
Background and location
Adar is an area southwest of Mabaan, which lies on the White Nile in Upper Nile state, and to the west of Ethiopia. The Khor Adar, which drains the Machar Marshes, flows through the region in a northwest direction to the Nile, which it reaches just above Melut. The Khor Machar swamps lie in a triangle north of the Sobat River and east of the White Nile. When flooded during the wet season, they extend for . The swamps and marshes are fed by local rainfall and by many small torrents from the Ethiopian foothills, which extend for along the eastern border, and by spill water from channels of the Sobat.
Discharge from the marshes along the Adar river is low except in years with exceptionally heavy rainfall. Most of the water is lost through evaporation before reaching the Nile. It has been proposed to build a canal from Machar via Adar to the White Nile to increase the volume of water flowing to Northern Sudan and Egypt, which apparently could be done without major environmental impact, but political instability has prevented the project from starting.
The Chevron Corporation discovered the Adar Yale field in 1981, shortly before the start of the Second Sudanese Civil War (1983–2005). Four exploratory wells had flow rates that exceeded a day. The oil is held in the Yabus Formation sandstone from the Paleogene age. The field has an area of about but the average pay zone is only . Initially the field was estimated to hold , but Seismic data acquired in 2000 pushed that up to . Also, three small oil pools were discovered south of Adar-Yale with another . Chevron started to pull out of Sudan in 1984 when three of its employees were killed, finally selling all of its Sudanese interests in 1992.
Development and production
Chevron suspended operations in 1984, and their concession was later divided into smaller units. In 1992 Gulf Petroleum Corporation-Sudan (GPC) was awarded the Melut Basin - Blocks 3 and 7. GPC was owned 60% by Qatar's Gulf Petroleum Corporation, 20% by Sudapet and 20% by a company owned by the National Islamic Front (NIF) financier Mohamed Abdullah Jar al-Nabi. The GPC consortium was reported to have invested US$12m in developing the Adar Yale field. In October 1996 GPC began to drill and reopen Chevron's wells and to build an all-weather road connecting Adar Yale to the garrison town of Melut.
President Omar al-Bashir inaugurated the Adar Yale site in March 1997. At first, production was just a day, taken by truck to Melut and then by barge down the Nile to Khartoum for export. Although export volumes were tiny compared to the field's potential, it was the first Sudanese crude to be exported and therefore had symbolic significance. In March 2000 Fosters Resources, a Canadian company, signed an agreement with the government of Sudan to develop the concession that covered most of the Melut Basin, including the Adar Yeil field, in partnership with a consortium of Arab and Sudanese companies. Fosters was forced to withdraw in May 2000 when its financial backing collapsed due to pressure from human rights groups. The U.S. government had been highly critical of Canadian involvement in Sudan oil development and in February 2000 the U.S. Treasury announced that American persons were forbidden to do business with the Greater Nile Petroleum Operating Company (GNPOC) and Sudapet.