Oil based well fluids with high solids content

An invert emulsion fluid having utility for drilling, completing, or working over subterranean wells, said fluid comprising:

• a) an oleaginous liquid, said oleaginous liquid comprising from about 30% to about 99% by volume of said fluid;
• b) a non-oleaginous liquid, said non-oleaginous liquid comprising from about 1% to about 70% by volume of said fluid;
• and
• c) an solids tolerance agent present in said fluid at a concentration of about 0.1% to 5.0% by weight of said fluid, said solids tolerance agent having the formula:
• 12
• wherein R is a C6 to C20 aliphatic group and R′ is a C2 to C6 aliphatic group and x has a value from about 1 to about 10.

A fluid having utility in subterranean wells, said fluid comprising:

• an oleaginous fluid and
• a solids tolerance agent that is the product of the reaction of an alkylene
• oxide with an imidazoline of a fatty acid having the formula
• 13
• wherein R is a C6 to C20 aliphatic group.

A method of forming a subterranean well, the method comprising

• drilling the subterranean well with a rotary drill bit and a drilling fluid;
• said drilling fluid including:
• an oleaginous based continuous phase and
• a solids tolerance agent that is the product of the reaction of an alkylene oxide with an imidazoline of a fatty acid having the formula
• 14
• wherein R is a C6 to C20 aliphatic group.

In a method of rotary drilling a subterranean well using a drilling fluid, the improvement comprising the use of a drilling fluid including:

• an oleaginous fluid;
• and
• a solids tolerance agent having the formula:
• 15
• wherein R is a C6 to C20 aliphatic group and R′ is a C2 to C6 aliphatic group and x has a value from about 1 to about 10.