2015ARKH-P5-Field Development Evaluation(80s)

TABLE OF CONTENTSPART 7 FDDP

FIELD DEVELOPMENT DECISION PROCESS

RESERVES UNCERTAINTIES

APPRAISAL PHASE & PRELIMINARY STUDIES

CONCEPTUAL STUDIES

PRE-PROJECT STUDIES

PROJECT PREPARATION & DECISION TO DEVELOP

EXAMPLE OF AN OFFSHORE FIELD DEVELOPMENT PROJECT

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MAIN PHASES OF E&P ACTIVITIES

New business

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PRODUCING FIELD FUNCTIONAL DIAGRAM

Injection injection

RESERVES (1) acts

Reserves are the technically & commercially recoverable quantities of hydrocarbons trapped in the reservoir.

Each reservoir is UNIQUE.

The recovery factor of an oil reservoir is in the range of 35 % of the Original Oil In Place (OOIP), and 70 % of the Initial Gas In Place (IGIP) for a gas reservoir.

The reservoir recovery factor always depends of the reservoir exploitation/depletion method: natural flow, artificial lift, water injection, gas injection, water / gas alternate injection ………

Reserves estimations are always subject to important UNCERTAINTIES. They are estimated by using probabilistic methods & simulations.

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RESERVES (2) acts

The PROVEN reserves = 1P or P 90 , i.e. there is a 90 % probability that the actual reserves are above P 90.

The PROBABLE (or MOST LIKELY) reserves = 2P or P 50 , i.e. there is a 50 % probability that the actual reserves are above P 50.

The POSSIBLE reserves = 3P or P 10, i.e. there is a 10 % probability that the actual reserves are above P 10.

The higher are the reservoir uncertainties, the bigger is the gap between P 90 and P 10

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RESERVES (3) acts

Companies formal reserves as indicated to the SEC – Security & Exchange Commission – are 1 P reserves.

2P reserves are used, in most of Oil & Gas Companies, for the base case of economic simulations (providing that economics are still robust with 1P reserves), and for sizing the production facilities.

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FIELD EVALUATION PROCESS

When an oil or gas discovery has been made, there are many key questions to answer (among many others):

What to do with this discovery ? develop/produce it, or not ?

How much oil/gas can be produced ?

Which development scheme to select ?

How much will it cost ? Is it an economical development ?

How long before production start-up ?

What are the risks ?

etc…

Development studies are performed to try to answer these questions and to hopefully be able to take a “go ahead” decision

More generally, the objective of the Field Evaluation Process is to define a development scheme allowing the optimization of the hydrocarbon recovery at the lowest cost, taking into account the reservoir uncertainties

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FIELD DEVELOPMENT STUDIES: OBJECTIVES AND KEY ACTIVITIES

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