After a bit of abuse, I put this to the LSE forum overnight, in search of a potential explanation, got plenty of the standard abuse lines but no answers
“The entire pack of rampers and pumpers are incapable of solving the riddle, so open it up to all now
Just explain this one thing, how can a flow of 42 barrels of oil per day for 88 hrs, only produce 24.8 barrels in that time.
Solve that riddle 88e have posed in their RNS, and you might get somewhere”
No one has offered a solve to the riddle, so I will offer one
Over the 88 hr period of flowback, described as natural flow back, this consisted of a series of stop start operations., rather than the continuous the wording suggests.
Typically starting with a period of N2 lift to begin the flow from the reservoir, the time in N2 lift is excluded from the 88hrs, but is added to the N2 assisted total, in total over a number of stop start flow sequences, this number reached 23.5 hrs of N2 Lift
The 88 hrs of natural flow is also broken into the same number of stop start sequences, the average flow rate in these was at a rate of 42 bopd for their duration. Note this is a 1.75 barrels per hour rate
As a worked simplified example, each day the flow test ran for 3.063 hours in natural flow mode, at 1.75 barrels per hour, which gives 5.36 bopd, produced to the stock tank per day
Multiply that by the 4.625 days in 111 hrs, and bingo 24.79 barrels in the stock tank, as announced by 88e
Obviously this is simplified to make it understandable, each day would have differences in production rates and run time, but the averages work, and it is those averages that predict the future flows
Should the suggested solve prove to be correct, it leaves some very big uncertainties around the reliability of short term, stop start flow data, as the well gets to recharge for long periods between flow sequences.
Whereas a reliable test would be a continuous period, during which the flow reaches a steady state, at a particular steady bottom hole pressure, where flow from the reservoir rock, matches flow into the 3 phase separator, without drawing down on a stored pressure build up
Further compounded by a very high gas to oil rate, more of a gas condensate reservoir than an oil one
A gas oil ratio of 1,450,000scf /24.8 bbl, or 1 barrel per ~58500scf of gas.
As a reference PANRs worst production result was 12000 to 14000 scf/barrel at the Alkaid 2 long term test of the Zone of interest, (some compare to a SFS). Then a much better 3000 to 4000scf/barrel in the SMDB reservoir at Alkaid 2
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