▎ 摘　　要

NOVELTY - Nano plugging agent comprises 500-600 pts. wt. white oil, 5 pts. wt. graphene, 5 pts. wt. modifier, 300-350 pts. wt. nano calcium carbonate, 30-50 pts. wt. nano silica and 20-40 pts. wt. stabilizer. USE - The nano plugging agent is useful in drilling fluid plugging. ADVANTAGE - The nano plugging agent has wide particle size distribution range, which can meet the plugging needs of nano pores and fractures in different shale formations during the drilling process. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparing nano plugging agent comprising (a) adding modifier to white oil, uniformly dispersing, adding graphene, uniformly dispersing to obtain graphene mother liquor and (b) adding stabilizer to the graphene mother liquor obtained in the step (a), dispersing uniformly and adding nano calcium carbonate and nano silica in sequence and uniformly dispersing; and (2) Use of nano plugging agent in drilling fluid plugging.