Here's some stuff to get you started:

http://www.hrw.org/reports/2003/sudan1103/8.htm#_Toc54492553

"The large-scale exploitation of oil by foreign companies operating in the theatre of war in southern Sudan has increased human rights abuses there and has exacerbated the long-running conflict in Sudan, a conflict marked already by gross human rights abuses—two million dead, four million displaced since 1983—and recurring famine and epidemics.

Forced displacement of the civilian population, and the death and destruction that have accompanied it, are the central human rights issues relating to oil development in Sudan. The government is directly responsible for this forced displacement, which it has undertaken to provide security to the operations of its partners, the international and mostly foreign state-owned oil companies. In the government's eyes, the centuries-long residents of the oilfields, the Nuer, Dinka, and other southern Sudanese, pose a security threat to the oilfields because control and ownership of the south's natural resources are contested by southern rebels and government officials perceive the pastoral peoples as sympathetic to the rebels. But the Sudanese government itself has helped to create the threat by forging ahead with oil development in southern territory under circumstances in which its residents have no right to participate in their own governance nor share the benefits of oil development. Brute force has been a key component of the government's oil development strategy.

The oil in the ground and flowing through the pipeline to the Red Sea supertanker port has driven expulsions from Western Upper Nile/Unity State, the area of the main oil production today. In earlier campaigns in the 1980s government troops and horsebacked militia of the Baggara, Arabized cattle nomads of Darfur and Kordofan, invaded from the northwest, destroying communities and expelling much of the population from the initial exploration areas, in Blocks 1, 2, and 4, dangerously situated on the north-south border of Sudan. (Map B)

In the 1990s the government embarked upon a more sophisticated displacement campaign, through the use of divide-and-conquer tactics: it bought off rebel factions and exacerbated south-south ethnic differences with arms supplies. Mostly Nuer factions with political and other grievances against the Dinka-officered rebel Sudan People's Liberation Movement/Army (SPLM/A, referred to as SPLA when discussing the military wing), emerged and a bloody south-south war ensued, concentrated in the oilfield areas. Campaigns of killing, pillage, and burning, enabled by government troops and air support for their southern allies who served as front troops, cleared the way for Western and Asian oil corporations to develop the basic infrastructure for oil extraction and transportation: rigs, roads, pumping stations, and pipelines.

The relationship of the war and displacement campaign to oil development is evident: the oil areas targeted for population clearance are those where a concession has been granted and a pipeline is imminent and/or nearby. The availability of the means of transport of oil to the market makes the nearest undeveloped block economically viable. The agro-pastoralists living there then become the target of forced displacement. Since 1999, when the pipeline was nearing completion and Blocks 1, 2, and 4 came on line with 150,000, then 230,000 barrels of crude oil produced daily, the main military theatre has been in the adjacent Block 5A. Oil revenues enable the government to increase its military hardware: it tripled its fleet of attack helicopters in 2001 with the purchase abroad of twelve new helicopters—used to deadly effect in the killing of twenty-four civilians at a relief food distribution site in early 2002, to cite only one example."

http://www.hrw.org/reports/2003/sudan1103/8.htm#_Toc54492561