▎ 摘　　要

Drilling fluid properties can be modified using a variety of nano-additives to achieve specific rheological and physical characteristics. Selected invert-emulsion drilling fluids modified with three different kinds of graphene oxide (GO)-based nanomaterials including GO, Cu(II) salen, and Cu(II) salen@GO were focused. The corresponding formation damage was evaluated through a set of core-flooding experiments and computed tomography analyses on selected carbonate samples followed by a set of wettability-based analyses and electrical conductivity measurements. The results were best fitted using the Casson model while the employed nano-additives were evidenced to have negligible effect on reducing the depth of penetration. In addition, GO- and Cu(II) salen@GO additives were observed to decline the contact angle for more than 20% and 35% in carbonate and sandstone samples, respectively, suggesting their potential to resolve the wettability alteration issues. Furthermore, electrical conductivity of the drilling fluid samples was increased for about 33 % using both Cu(II) salen and Cu(II) salen@GO additives. (C) 2020 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.