RE: Aquifier14 Jul 2020 12:08
Hi AquaeSulis01,
"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."
Technically speaking, let's say that water is drawn from the perched water reservoir by well 7z due to the pressure difference between the oil reservoir and the perched water reservoir - (i.e. due to oil extraction, pressure in the well decreases --> therefore water from the higher pressure perched water reservoir moves to the lower pressure oil reservoir).
Now, since water has entered the oil reservoir, it will most likely have a residence time (time taken for water from entering the oil reservoir to reach the pump) before it is pumped up by the ESP.
Water has more density than oil (i.e. oil floats). By Stokes' Law (engineering law), water will settle to the bottom of the reservoir given enough time to settle. It's very likely that not all the water that is drawn from the perched water reservoir is pumped up.
Best case scenario would be that MOST of the water settles, allowing the oil/water separation to take place - and thus, the ESPs will mostly be exposed to oil.
Having said all that, I honestly don't know how fractured basement would affect the above.
ALL IMO. Slift.