ULTRA-HIGH SALINITY SURFACTANT FORMULATION

Methods of enhanced oil recovery are disclosed that use compositions including an alkyl polyether anionic surfactant having the general structure R1JA, wherein R1 is a C8-C18 primary or secondary radical group, J is a random, block, alternating, or alternating block polyether segment having the structure [(PO)x(EO)y(BO)z], wherein x is 4 to 18, y is 0 to 20, and z is 0 to 5, and A is an anionic group; a co-surfactant having the general structure (R2)q(B)Ph-L-Ph(D)(R3)r, wherein R2 and R3 are each, independently in each instance, a C8-C24 linear or branched, primary or secondary alkyl group, B and D are anionic groups, q is 1 to 3, r is 1 to 3, and L is O or CH2; and an alkoxy alcohol.