dspp wrote:New paper out, link spotted courtesy Carcosa:
https://www.hurricaneenergy.com/downloa ... ce/480/258
An integrated approach for fractured basement characterization: the Lancaster Field, a case study in the UK
Daniel A. Bonter* & Robert Trice
Received 24 October 2018; revised 18 July 2019; accepted 26 July 2019
Note July revision dates ........
I've had a chance to read this, and very straightforward it is too, both as a paper and as a description of their workflow and issues. There is clearly a good team on the job.
They do appear to have a continuum fracture sizes ranging from micro-fractures through joints to large aperture fault/fracture zones, which is as we have been led to believe. Overall it is exhibiting the classic dual porosity response. The two producer wells seem (my tally) to be encountering somewhere between 10-20 of the larger vertically oriented fault/fracture zones, and given the geometry and spacing some of these are shared - so perhaps 10 each (?). They have so far mapped approx 740 faults from top seismic and (this is work in progress, suggesting - as is alluded to in the paper - considerable mandraulic aspects) these are so far less well mapped to the east side of Lancaster (and not at all in Halifax one guesses).
So say targetting 20 per producer and say 800 in toto (ignoring Halifax) then that would be 40 wells per field. That sounds about right to empty a 500 mln bbl STOIIP field in a reasonable time at a reasonable recovery fraction. That means plateau production of 400,000 bbl/day from Lancaster alone. That is (say) three 120,000bbl/day FPSO units. So starting with one you need to place it sensibly so as to leave decent acreage for the subsequent second or third floater and its associated wells.
They comment that the low aquifer case can be pretty much discounted.
"In fact, there is no difference between the two and by using a high-resolution simulator the static model can be taken straight through to dynamic simulation with no alterations or upscaling." Wow. I can see the necessity/desirability to do so, but the ability to do so is phenomenal. Roll on putting the Tesla HW 3.0 into this sort of environment, both for semi-automated feature identification, and for the reseng modelling. It really is a different world these days.
Turning to something that is not in this paper.
So far people have been using the term below structural close to refer to the issues with the poroperm encountered in WD. Elsewhere I note that the very attractive properties of the Lancaster rock is associated with its sub aerial nature, at least for long periods of its history. I do wonder at what depth in Lancaster that assumption breaks down. Similarly at what depth does it break down, or hold true, in Warwick and Lincoln, and maybe Halifax. I appreciate that the risk-averse around here will not be keen to drill horizontal appraisal wells in the deeper reservoir, but at some time (pre-monetisation/exit) it will be necessary to do so if only to withstand people like me saying "everything deeper than a producing well can be discarded in valuation discussions".
As an aside I have commented before that there is not much public domain freebie info on Clair basement. I have previously speculated that maybe biodegradation could be an issue in Clair basement. I now also wonder if Clair basement has been as well weathered - and left in that state - or whether it too suffers from WD's poor poroperm. If so, then value to BP of the HUR knowledge base will be limited, and so that card - in respect of Clair - will not be as valuable to HUR in any discussions with BP.
It is worth reading.