Mandurah: this bit (in bold) wasn't right. Forget about lead, mislead, blindfolded or punch-drunk interp's as every one will interpret things differently given the lack of clarity from their last release. So pointless blaming each other.
I am well aware of the formula R = {GRV x N/G X POR X Shc/FVF} x Er.
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The above formula is Incorrect b'coz
it's incomplete, so whatever result one ends up using this will b incomplete. Strangely enough no one pointed this out so far! Even Tim covered that in his post back in the emails.
My points are as under:
Firstly u need to know the '
units' for the GRV (area in sqkms & thickness in metres). Assuming it's in metric then multiply the above by 6.29, without which u'll end up with a lower number. Or the old school where the Area is in acres, thickness in feet then use 7758. Either way the end result is still the same in mmbbls.
eg: 6.29 *45km2 * 30m net * 24% phi * 72% oilsat * 75% shrinkage * 30% RF = 330 mmbbls ballpark
or 7758 * (247.1*45)* 98ft * the rest = 330 mmbbls rec.
One can run the above calc's for diff scenarios ie,
- varying areal extents, eg: 25, 30, 35, 40, 65, 90, 110 km2,
- variable netpay eg: 15, 25, 30, 35, 40, 45m &
- poro ranging from 18 to 24% to get multiple iterations or range of estimates.
- recovery factors of say 18-20-30% for the thick & thin sands. and so on
(End of the day an Operator has multiple models called Static using fixed variables and Dynamic which uses actual field data per producing Sand). Detailed modelling is outside the scope of discussion on Hotcopper.
Secondly, the above calc is
ballpark back of the book calcs, as it doesn't tell u the estimates from P99 to P1, which is done using propreitary software (ie Herbie goes to ..) & an Operator releases the low-mid-high & mean estimates (is P90-P50-P10 or Mean rec resource in MMbbls) or 1P-2P-3P reserves when Commerciality is established.
Thirdly, with only 2 wells drilled in the core of the Field, pressure gradient is always the key going fwd besides the netpay, poro, perm, Oilsat etc etc. An Operator also conducts a '
productivity index' testing at the end of the well using injectible dyes to work deliverability of the reservoir. The end result is what giveth them the confidence of final production results, eg bbls/psi/day & number of producers/injector wells required to drain it via long laterals, dual laterals, tri-laterals etc. This has been done on a regular basis on various fields with varying field life of 3-30 years with or without compartments or fault/shale barriers.
Fourth, they r still appraising so the final reserves will change as per the confidence in the acquired subsurf data (ie WL logs & Actual poro/perm/density, recovery estimates from core slabs post-SCAL studies, XRD studies, Gas Oil Ratio analysis etc).
Last but not the least, the '
drive' for the SNE field reservoir, matters the most. Whether there's a gascap in conjunction with an acquifer or gravity drive will help in the final locations of any gas & water injectors when heading into Development/Exploitation phase.
So thats' the long & short of it.
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Also as per
chapter 5, section 5.30 of the ASX guidelines a listed entity on the ASX
must report the
net pay, Test intervals & other bits & bobs.
Refer
pg-15 & related
sub-points from the link provided below.
http://www.asx.com.au/documents/rules/Chapter05.pdf
I think LTA's key argument was lack of info on the actual 'net oil pay' & test intervals at SNE-2 from the ASX release dt 4th Jan which is justified. Lack of relevant details is bound to confuse many.
So hope Cairn or any analysts covering them in their
19th Jan on Tuesday's Q&A actually report & probe more on details from SNE-2 findings & fiscal terms etc. Forget about Core results etc as that will take months. After this call, there's the
15th March conference on 2015 preliminary results. See Cairn's schedule below.
http://cairnenergy.com/index.asp?pageid=110
As usual, this post will b caught between the xFire betwn the vigilantes & shenanigans. Good luck to both as neither party understands the fundamentals of Petroleum Exploration, no offence intended to either.
(20min delay)