Oil-based drilling fluids for high pressure and high temperature drilling operations

A method for making an oil-based drilling fluid composition comprising:

• mixing a base oil, at least one emulsifier, at least one emulsifier, and optionally at least one wetting agent to form a first mixture, in which the at least one emulsifier comprises an amino amide comprising the formula R—CO—NH—R′—NH—R″—NH2, where R is a fatty acid alkyl and R′ and R″ are alkyl groups;
• optionally, mixing at least one rheology modifier, and alkalinity adjuster into the first mixture to form a second mixture;
• optionally, mixing at least one fluid-loss control additive into the second mixture to form a third mixture;
• mixing a brine solution into the first mixture or the third mixture to form a fourth mixture;
• and
• mixing a weighting additive into the fourth mixture to form the oil-based drilling fluid composition.

A method for drilling a subterranean well, the method comprising:

• providing an oil-based drilling fluid composition;
• and
• introducing the oil-based drilling fluid composition into a wellbore;
• wherein the oil-based drilling fluid composition comprises:
• an oil phase comprising a base oil;
• an aqueous phase comprising water;
• at least one emulsifier, in which the at least one emulsifier comprises an amino amide comprising the formula R—CO—NH—R′—NH—R″—NH2, where R is a fatty acid alkyl and R′ and R″ are alkyl groups;
• and
• one or more additives chosen from a wetting agent, a rheology modifier a fluid-loss control additive, and a weighting additive.