RE: Aquifier14 Jul 2020 11:08
Planted, from the Apr Production RNS "After retrospectively analysing the drilling and petrophysical data with the benefit of the EPS data the following conclusions have been drawn:
· a 10m high permeability water bearing zone has been identified within an interpreted 40m producing interval in the 205/21a-7Z well;
· a 10m water zone has also been identified in the 205/21a-6 well, however this water zone is more distant from the interval currently producing;
· produced water from the 205/21a-6 well is therefore interpreted as being drawn from the perched water zone intersected by the 205/21a-7Z well; and
· current individual well water cuts of approximately 46% in 205/21a-7Z and 7% in 205/21a-6 during April are consistent with this revised interpretation, noting that the 205/21a-7Z figures were impacted by high water cuts immediately after a shut-in at the start of the month.
The behaviour of produced water combined with the drilling and petrophysical data has led to an interpretation that the water produced by the Lancaster EPS is being sourced from a zone of 'perched' water. Perched water is isolated from the underlying aquifer and therefore has a finite volume relative to the life of the field. The perched water model would imply that once a constant production trend has been set, water production levels should stabilise over time and may eventually decline"
So two points, there is more than one area of perched water with estimates as to the length of the zones, and the word "may" eventually decline is used i.e. may mot drain away. Until successive production reports indicate stability in the watercut, then many will remain on the sidelines and this sp will stagnate