abstract |
A gelled organic-based fluid system and method of forming and using the system. The fluid system is prepared by gelling an organic solvent, a viscoelastic surfactant, and a nitrogen compound having a free electron pair such as urea in an amount effective to both increase viscosity and increase a rate of breaking the viscosity, relative to the gelled system without the nitrogen compound. In a further aspect, the method is used to treat a well penetrating a subterranean formation, for example, in a coiled tubing cleanout, or the like. |