A five spot is an injection pattern in which four injection (or treatment) wells are located at the corners of a square and the production well sits in the center. The four injection wells are treated with the binary mixtures simultaneously or near simultaneously. The resulting pressure drive and heat is displacing the oil towards the central production well.
Depending on the size of the field and the oil, the central production well might be treated initially using the cyclic injection method.
The five spot treatment typically has a higher efficiency than the cyclic injection method and sweeps out more oil. The downside are slightly higher upfront investment cost and the uncertainty of treatment duration until a communication between the wells is achieved.
The injection pattern is inverted with the four production wells being located in the corners of a square and the injection well in the center. The treatment sequence is otherwise the same as with the five spot.