A method for creating chemical surface blocking agents for enhanced oil recovery.

A method of increasing recovery of liquid hydrocarbons from subsurface reservoirs, and particularly from those located in tight formations is disclosed. One aspect includes calculating the in situ fractured formation wettability from real time measurement of flowback volume and composition.

A method of selecting an injectate for recovering liquid hydrocarbons from a reservoir includes designing a plurality of injectates, calculating a net present value of each injectate, and selecting a candidate injectate based on the net present value. For example, the candidate injectate may be selected to maximize the net present value of a waterflooding operation.

A method of recovering liquid hydrocarbons using an injectate includes recovering the liquid hydrocarbon through primary extraction. Physico-chemical data representative of electrostatic interactions between the liquid hydrocarbon and the reservior rock are measured.

A method of designing an injectate to be used in a waterflooding operation is disclosed. One aspect includes specifying data representative of chemical characteristics of a liquid hydrocarbon, a connate, and a reservoir rock, of a subterranean reservoir. Charged species at an interface of the liquid hydrocarbon are determined based on the specified data by evaluating at least one chemical reaction.