1. n. [Enhanced Oil Recovery]

A gasflood process in which a lean gas, for example methane, nitrogen or carbon dioxide, is injected into a reservoir to achieve multiple-contact miscibility. Upon contact with the oil, light and intermediate molecular-weight hydrocarbons transfer from the oil into the gas phase, thus vaporizing into the gas. Formation of miscibility may require several contacts between gas containing vaporized components and fresh reservoir oil. If the injected gas becomes sufficiently enriched with these components that miscibility results with the oil, then the lean gas and oil have multiple-contact miscibility. A forward multiple-contact test is a laboratory evaluation of a vaporizing drive process. In the field, both forward- and backward-contact processes can occur during a given gasflood.

See: backward multiple-contact test,  condensing drive,  forward multiple-contact test,  gas injection,  lean gas,  multiple-contact miscibility