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(don't get confused with Estimated Ultimate Recovery which is equivalent to STHCR).
Both formulas above do not have a practical meaning as Petroleum Production, accounting and sales are managed separately for Oil and Gas (see Oil Reserves (OR) and Gas Reserves (GR)).
Unlike Hydrocarbon Initial In Place (HCIIP), which is a geological category, the concepts of current Hydrocarbon In Place and Hydrocarbon Reserves depend on the parameters of FDP based on recovery method, recovery duration, surface logistics and economics.
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