1. prep. [Geology]
Located up the slope of a dipping plane or surface. In a dipping (not flat-lying) hydrocarbon reservoir that contains gas, oil and water, the gas is updip, the gas-oil contact is downdip from the gas, and the oil-water contact is still farther downdip.
Antonyms: downdip
See: dip, gas-oil contact, oil-water contact, reservoir