RE: CMD Presentation13 Jul 2019 23:43
The dismissal of the water cut in 7Z plus his body language suggests he was (as a geologist) not that comfortable with the technical issue (being dynamic, engineering theory). Perched water in hydrocarbon reservoirs is a poorly researched topic (very good presentation was given couple of months back at LPS by Shell) whereby due to hydrocarbon filling of initially water filled rock, some pores (fractures in FB) end up with mobile water still in 'dead-end' pores. The HE picture clearly is wrong as it is not 'dead ended' where depicted water bearing. These dead-end pores therefore contain mobile water - not irreducible water (as quoted in the CPR - which Dr R-T stated incorrectly to another question!) which is predominantly capillary bound above the transition zone (other question in Q&A! - also poorly answered), BUT, at oil columns pressures (refer pressure plot with oil pressure line and water pressure line crossing at theoretical OWC). Hence in 7Z both oil and (perched) water are mobile therefore the water cut is constant with typical drawdown ranges production tested (which Dr R-T said initially - but - later said water-cut would go down if flow at lower rate(!) - not consistent with perched water!). The 100% proof will be if it is perched water (mobile water from dead-end pores will not be that large a volume in regions above closure - even decreasing volume further towards the crest) then water cut in the near future will be still 8% but slowly decreasing as the dead-end water is depleted/produced... Early water production is expected in all reservoirs with perched water contacted along the producer - but this is not irreducible water (1 - 10% in CPR! (which was wrong answer by HE)).
As HE ramp up 6 & 7Z, water cut will be watched - but has not bearing on meeting the 20,000 BOPD rates (IF perched water - which is most likely as the water pressure seems to be consistent with oil pressure - ie stable rates achieved very quickly in May). With WD perched water rate was 600 BWPD at 1000psi DD - in Lancaster 7Z with minimal DD at 15,000 BPD (say) => 1200 BWPD plus 13800 BOPD. 6 can flow 15,000 BOPD therefore 7Z needs 5,000 BOPD with around 400 BWPD (ie negligible). With WD, clearly volume of perched water is much higher - but in poor permeability fractures -- below structural closure. ie drill at crest! 6 well higher up on structure than 7Z...
Agree 100% CMD was good day but next week SP will see how other investors mark HE presentational skills...