| 摘要 |
<p>A self-triggering, in-situ crosslinking fluid system is provided for controlling lost circulation for drilling in a carbonate formation. Methods of drilling a well include the steps of: (A) forming a drilling fluid comprising an aqueous phase, wherein the aqueous phase comprises: (i) water; (ii) acid, wherein the acid is at least sufficiently strong and in at least a sufficient concentration such that the aqueous phase has an initial pH of less than about 2; (iii) a viscosity-increasing agent; and (iv) a crosslinker, wherein the crosslinker is selected or controlled to crosslink the viscosity-increasing agent at a pH range anywhere in a range of about 1.5 to about 6.5 and that is at least higher than the initial pH of the aqueous phase; and (B) drilling with the drilling fluid to form a wellbore penetrating a subterranean formation.</p> |
