US 12,227,690 B2
Monovalent brine-based reservoir drilling fluid
Clotaire-Marie Eyaa Allogo, Sugar Land, TX (US); Raymond Ravitz, Houston, TX (US); and Sooi Kim Lim, Aberdeen (GB)
Assigned to SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US)
Filed by Schlumberger Technology Corporation, Sugar Land, TX (US)
Filed on Aug. 22, 2023, as Appl. No. 18/453,397.
Application 18/453,397 is a division of application No. 15/742,869, granted, now 11,767,457, previously published as PCT/US2016/041411, filed on Jul. 8, 2016.
Claims priority of provisional application 62/189,990, filed on Jul. 8, 2015.
Prior Publication US 2023/0392065 A1, Dec. 7, 2023
Int. Cl. C09K 8/08 (2006.01); C09K 8/504 (2006.01); C09K 8/512 (2006.01); C09K 8/514 (2006.01)
CPC C09K 8/08 (2013.01) [C09K 8/5045 (2013.01); C09K 8/512 (2013.01); C09K 8/514 (2013.01); C09K 2208/18 (2013.01); C09K 2208/24 (2013.01); C09K 2208/26 (2013.01)] 9 Claims
 
1. A method of drilling a subterranean well, the method comprising:
drilling the subterranean well while circulating a wellbore fluid in the subterranean well, wherein the wellbore fluid comprises:
an aqueous base fluid comprising a monovalent brine;
a modified starch; and
a mixture of divalent metal oxides present at a concentration ranging from 2 pounds per barrel (ppb) to 5 ppb; wherein the wellbore fluid has no more than 3 wt % of alkaline earth metal in the wellbore fluid.