American foreign policy decision makers altered their understanding of the sovereign territorial state on September 11, 2001. The loss of lives and property in New York City, Washington, DC, and Pennsylvania reversed America's general belief that the oceans and superpower status guaranteed “home security.” That dramatic act of violence against civilians and symbols of U.S. culture crystallized the distinction between the ideologies of democracy and terrorism, which in turn forced geopolitical horizons to expand beyond traditional thinking.

In a once in a lifetime ethnic convergence, the strong Irish American leaders of Congress and the White House joined together to cajole, persuade, and lobby the State Department in its formation of Irish foreign policy. But if diplomatic changes in U.S. policy toward Ireland and Northern Ireland were made public after a private struggle between Irish American leaders and the government's advocates of status quo, then the economic changes in U.S. investment have been obscured by the public debate between Irish Americans who seek increased investment and those who seek to limit investment. However, economic factors are not the primary determinant in Irish development as much as the political factors that decide which enterprise is to be established where, how it is to be financed, and when such investment is to be actualized. A case is made that the recent changes in the leadership of the important Irish American groups, which at one point in the 1980s did play a constructive role in forming Irish foreign policy, has now allowed the President to return to a more centrist diplomatic and economic policy.

Oil based fluids have been used since the inception of well completion technologies. Formation sensitivity to water has often been the primary consideration for the selection of oil based stimulation fluids. Historically, oil based fracturing designs required complicated procedures to successfully execute a fracturing operation. Rheological properties of fluid compositions used did not produce stimulation fluids with optimum viscosity or transport characteristics. The obvious hazards involved in accomplishing an operation using these types of fluids were also great due to the variability of the fluids caused by different base hydrocarbons. The development of a unique system with rheological, transport, and process advantages, which have long been desired in hydrocarbon based stimulation fluids are discussed in this paper. In addition, the chemical evolution of the oil based gel system will be discussed, and properties of the fluid including rheology, break, and conductivity testing will be presented. Characterization of the rock mineralogy for those formations which can be considered as candidates for stimulation with the hydrocarbon based system are presented. Detailed field case histories of the application of the new system are included. In general, stimulation with the new system provides a rapid clean-up and return to production. Introduction/Statement of Problem Since the late '80s, an important focus for the drilling activity in Canada involves the deep Cretaceous / Jurassic gas formations in the foothills of West Central Alberta. These formations contain water saturations at sub-irreducible levels and are generally relatively low in permeability (0.1 to 1.0 millidarcies.) with temperatures in the range of 70C to 110C. In addition, they usually contain or form condensate during production. These conditions along with the availability of highly effective phosphate ester gelling agents and improved crosslinkers and breakers have given rise to the widespread use of gelled condensates and refined oils as fracturing fluids. The inertness and non clay-swelling nature of hydrocarbons as well as the low interfacial tensions obtained with high pressure gas, leads to superior regained permeability results when compared to water based fracturing fluids. In 1995, however, three refineries located in British Columbia, Alberta and Ontario all experienced rate limiting fouling in the jet draw area of their distillation towers. subsequent shut down and inspection revealed that all three refinery towers were fouled with a glue-like compound that appeared polymeric in origin. Analysis showed that the deposits contained (8–12%) phosphorous in addition to carbon (30–40%) hydrogen (3–4%), nitrogen (3–7%) and copper/nickel (1–2%). subsequent studies into the volatility of phosphorous-containing additives, that could have contaminated crude oil feed stocks, showed that only the phosphate esters used in gelled hydrocarbon fracturing fluids were volatile and likely to be the source of the problem. Although phosphate esters had been used for many years with out any reported fouling, the greatly increased frequency of these fracture treatments and the higher through puts and reduced inventories of crude at refineries in recent years helped rationalize the findings. subsequent to the 1995 fouling incident, monitoring of phosphorous levels in the crude feeds was undertaken. For the next couple of years, there was little evidence to show that there was a continuing problem. However, in 1997 occasional spikes in concentration of phosphorous in the crude streams were observed and, in 1998 inspection of distillation towers showed that phosphate deposits were still occurring in all three towers. Even though many questions remained, it was felt that if phosphorous could be eliminated from the gelled fracturing fluids then the formation of deposits and subsequent fouling could be eliminated.

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