Glossary

UKCS

United Kingdom Continental Shelf.

Unconformity

a tectonic feature in which strata are eroded and subsequently overlain with younger strata (sometimes angularly), which are said to lie unconformably on the older strata; the actual boundary between the two sets of strata.

Unconformity trap

a trap in which the escape of hydrocarbons is prevented by impervious rocks unconformably overlying the reservoir

Unitisation

when owners or oil and/or gas reserves pool their individual interests in return for an interest in the overall unit, which is then operated by a single company on behalf of the group, thus increasing efficiency.

Updip

the opposite of downdip.

Upstream

those activities relating to the exploration, production and delivery to an export terminal of crude oil.