Patent ID: 6034037
Filing Date: 2000-03-07
Classification: C09K,Y10S

Abstract:
A method for drilling a borehole in a subterranean formation, the method comprising the steps of:(A) rotating a drill bit at the bottom of the borehole; and(B) introducing a drilling fluid into the borehole to pick up drill cuttings and to carry at least a portion of the drill cuttings out of the borehole, where the drilling fluid comprises:(I) at least one additive selected from the group consisting of emulsifiers, wetting agents, viscosifiers, weighting agents, and fluid loss control agents; and(II) a base fluid comprising a plurality of hydrocarbons, where the hydrocarbons comprise (a) a total combined concentration of iso-paraffins and n-paraffins of greater than 90 weight percent, (b) at least 1 weight percent hydrocarbons containing 11 or less carbon atoms, (c) at least 5 weight percent hydrocarbons containing 13 or less carbon atoms, (d) at least two hydrocarbons containing a consecutive number of carbon atoms, and (e) at least 2 weight percent iso-paraffins.