Part of total Hydrocarbon In Place (HCIP) in petroleum reservoir which can be recovered to the surface under specific FDP. 

It comprises Oil Reserves (OR), also called Recoverable Oil, and Gas Reserves (GR), also called Recoverable Gas.

The volumetric value of HCR in NTP conditions is given by STHCR.

There are different ways of classifying reserves based on their volume and structure.

See Also

Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petroleum Geology /  Petroleum Reservoir 

[ Exploration ][ Booking Reserves ] [ Reserves Classification ] 

[ Oil Reserves (OR) ] [ Gas Reserves (GR) ]