Can a Marcellus Shale well previously drilled to the kick-off point and then later plugged be converted to a new Utica well? Is everything the same from the surface down to kick-off points in a Marcellus or Utica well? Where is the plug located...at the kick-off point or another point up the well?
Think of the cost savings!!
I do not think it is possible for several reasons, the pressure differential between Utica and Marcellus wells being just one.
Think of a long metal straw going down from the surface 8,000 feet to a Marcellus well.
The entire hardware must be able to contain the highest expected pressure which, I believe runs about 3,000 psi to over 4,000 in Susquehannah county.
The deeper Utica wells, from 10,000 to 13,500 feet vertical depth, regularly exceed 7,000 psi up to 10,000 psi Flowing Casing Pressure for monsters like the Scotts Run and the Gaut.
Intermediate size casing must be installed in a telescopic fashion - cemented throughout the process - to ensure well integrity.
And just as a quick PS regarding Utica wells, XTO (Exxon), Chevron, and even Chesapeake have taken out very recent permits targeting the Utica/Point Pleasant formations.
There is a GREAT deal of anticipation regarding future Utica potential, but maintaining long lasting conductivity to the wellbore has been a major problem.
Here is another thought; in NC PA, the Marcellus and the Utica formations have different planes. What I mean by that is, one formation is sloping gently towards the surface as the rock goes North, while the other formation slopes away from the surface as the rock goes North.
With the well completion reports I have seen, the operator begins to turn away from vertical at some point in the downward wellbore, trying to enter the formation at roughly the same plane.
So after all that, it may not be feasible to change formations from the same kick-off point.
I think I need to restate my question in a different way. There are many wells intended for the Marcellus layer drilled to the kick-off point and then plugged and abandoned. Can this same vertical well be used a second time for a Utica well? The cost savings would be substantial.