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Permalink Reply by Skip Peel - Mineral Consultant on August 21, 2018 at 14:28

Haven't heard "whipstock" used in conjunction with a horizontal well in a while.  Actually years.  When early horizontal wells, Haynesville and CV, drilled a pilot hole to determine the landing zone, it was normal to see a report to the effect that the driller would move back "up hole" and mill a "window" in the well casing then set a whipstock to kick the drill bit out of the casing and off in the direction of the planned lateral.  Then you would also see the report "building the curve".  I suppose that these are no longer regular subjects of reports because there is no need to drill a pilot hole in most situations and steerable drill bits no longer need help to go in the right direction.  There are 14 named CV Sands and some are quite thin so it might make sense to drill through the entire section in order to determine where to place the lateral.  The whipstock is not necessarily a sign of a problem.  Redrilling the lateral could indicate a couple of issues.  The original lateral may have gotten out of the landing zone and could not be steered back into the proper alignment.  Could be that there was a mechanical problem with the original lateral and it was easier to drill a new one instead of trying to adjust the first one. 

A whipstock is a curved steel wedge which is put into the borehole to start off the drilling of a new branch. Lateral deflection of the wellbore has been achieved by placing a wedge or whipstock in the well.

Looks like they lost the first lateral about half way to the planned lateral length.  The problem may have been in the vertical section of the wellbore because they had to sidetrack.  Just guessing at this point with the limited information available.

WORK PERMITS

REFERENCE NUMBER	APPLICATION DATE	EXPIRATION DATE	WORK PERMIT TYPE	WORK PERMIT STATUS	WORK PERMIT STATUS_DATE	TOTAL DEPTH	WORK_PERFORMED	DOCUMENTATION RECEIPT DATE	TEST SAND	WORK DESCRIPTION
778-18-5-6	08/01/2018	08/01/2019	SIDETRACK	APPROVED	08/01/2018	0	N			PLUGBACK SIDETRACK

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Permalink Reply by ray schmidt on August 21, 2018 at 14:49

Thank you for your willingness to school us with your expert advice. I appreciate it greatly! 

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Permalink Reply by Skip Peel - Mineral Consultant on August 21, 2018 at 14:51

You're welcome, ray.  I'm a landman, not a driller, so this is my best stab at what is going on with this well.

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Permalink Reply by Rock Man on August 21, 2018 at 17:14

Another reason to sidetrack would be sticking drilling assembly / tools in the hole and not being able to recover the "fish". Sticking tools is a frequent happening but normally this equipment can be recovered after some effort is made to recover the fish. But worst case scenario means abandoning that wellbore, pulling back and starting over via sidetrack and /or whip stock

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Permalink Reply by ray schmidt on August 22, 2018 at 2:03

Thank you for your help Rock Man!

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