There are so many comments/questions on this thread that need answering and it shows the value of places like HC so that these sorts of question can be asked and answered.
Let me put my 2c worth in (despite not being a holder) and try to deal with just one of them this time around. It mainly concerns the concept of "horizontal" drilling.
In simple terms, horizontal drills start off as vertical (or near vertical) wells just like any other and at a certain depth, taking into account the curvature that can be achieved and maintained based on the equipment and diameter of the hole, the directional drill head is used to start angling the drill stem.
As you get deeper and build more angle, you are effectively putting a bend into the steel pipes, but it happens over such a distance that it can be maintained. Eventually, with enough bending of the drill you can end up with the drill head moving horizontally (or near enough) to the surface.
Now of course the ideal point at which to have the hole move to the horizontal is right in the middle of the productive zone. If you get it right then you get to put a few hundred metres of collection tube into what might be a layer that is only a few metres thick when measured vertically, thereby drastically increasing your flow rates. If it's a tight formation (as most shales are) then you get the added benefit of being able to fracture stimulate a large contact area and thereby drain it more effectively.
The chances of them using the existing holes are minimal given that they would be looking to begin building angle at a relatively shallow depth (with productive zones just 770m down in M-1) so there would be little benefit in using an existing well and some risk that the well bore could be damaged since it was drilled so long ago.
The reference to twinning these wells is more likley meant to indicate that the wells will be drilled close together so that the knowledge gained from the well logs of the M-1 well, remains valid in terms of controlling the M-2 well.
Remember, we are looking to drill a well more than 3/4 of a Km down underground and gradually bend it so that by the time it gets to be horizontal, it is at a specific depth where we "know" the oil is. You can't drill straight down until you hit the oil then make a right turn and drill for 500m. It just doesnt work like that.
Now think about the underground geology. At the M-1 well we know that the oil is at 770m. I can't remember how thick this layer is and can't be bothered looking it up but let's assume it's 5m thick. How far do you think I would have to move in any direction before the layer is no longer at 770m?
I don't know and neither does anyone else really, because there's no seismic, so the best idea would be to step away from the well a little, and start my M-2 drill with the aim of having it head directly towards M-1 where I know the oil is at the 770m level and to design my well plan to make sure that I go close to the original well, reaching "horizontal" as I get to it.
The data collected from the logs of the M-1 drill will include details on the exact depths at which all the various formations appeared while drilling. This information is very important for well control on the M-2 drill as I can start to get an idea of how the layers have been bent/folded or whatever underground. If I find that each of the layers I drill through in the second well are appearing at slightly lower levels then I can make some judgement that the layers slope downward on a line from the first well to the second. That's a 2d observation and may not turn out to be entirely correct but it's still better than drilling blind.
Pretty simple hey!!!
Cheers
Badfish
BKP Price at posting:
1.9¢ Sentiment: Buy Disclosure: Not Held
