High temperature stable aqueous brine fluids viscosified by N-heterocyclic organophosphorus compounds

摘要

There is provided an aqueous brine fluid containing an N-heterocyclic organophosphorus compound which serves to increase the viscosity thereof. These viscosified brine fluids are particularly useful in drilling operations, most especially as solids-free drilling, completion, packer and workover fluids for drilling operations involving deep wells.