▎ 摘　　要

NOVELTY - Composition comprises modified graphene oxide, anionic surfactant, cationic surfactant and composite solvent. USE - The composition is useful in oil layer cleaning agent for cleaning wellbore and formation descaling (all claimed). ADVANTAGE - The oil layer cleaning agent has functions of wetting, penetrating, dispersing and peeling off organic deposits, the agent can efficiently prevent the redeposition of organic matter e.g. wax, colloid and asphaltene in the near wellbore zone, so the construction period is long and the effect is remarkable. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) a method for preparing composition, comprising mixing modified graphene oxide, anionic surfactant, cationic surfactant and composite solvent; (2) an oil layer cleaning agent, comprising the composition; (3) a method for cleaning a wellbore, comprising using the oil layer cleaning agent; and (4) a method for formation descaling, comprising using the oil layer cleaning agent to carry out scaling to the formation, specifically including diluting the oil layer cleaning agent with clean water to obtain solution II, injecting the solution II into the formation, shutting in the well, and descaling, where in the solution II, the amount of the oil layer cleaning agent is 10-25 wt.%, and the conditions for descaling are: descaling time 8-24 hours, and the descaling temperature is 30-360degrees Celsius.