Patent ID: 7829509

Claim:
A packer fluid, comprising: a water-miscible solvent, comprising about 50% to about 80% by weight of the packer fluid; a viscosifying additive; a crosslinking agent having the facility to crosslink the viscosifying additive; a crosslinking inhibitor having the facility to inhibit crosslinking between the viscosifying additive and the crosslinking agent; and an initiating agent having the facility to overcome an action of the crosslinking inhibitor and to initiate crosslinking between the viscosifying additive and the crosslinking agent, wherein the packer fluid has a thermal conductivity of no more than about 0.25 btu/(hr·ft·° F.), and a potential to substantially increase its viscosity upon sitting for a selected period of time; and wherein, upon sitting for a selected period of time, the increased packer fluid viscosity and the packer fluid thermal conductivity concurrently reduce convective and conductive heat transfer, wherein the crosslinking inhibitor comprises hydrochloric acid.