Refers to Petroleum Hydrocarbon initially to all Petroleum Hydrocarbons initially present in Petroleum Reservoir before the anthropogenic invasion.
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The volumetric value of Hydrocarbon Initial In Place (HCIIP) in NTP conditions is given by STHCIIP :
The changes in STHCIIP over time can be caused by production from a given petroleum reservoir or because of the hydrocarbons migration caused by production at offset hydrodynamically connected petroleum reservoirs.
See Also
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Petroleum Industry / Upstream / Exploration / Booking Reserves
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