What’s the plan if the sidetrack fails?, page-64

I would have thought that the risk of tools getting past the coal layers on wireline is a low risk? Every well and sidetrack so far (MK1/ST and MK2) has completed at least two runs to TD on wireline.

I’m expecting that the biggest risk of the coals is only going to come into play if we see differential sticking and need to run the MDT tool on pipe and then the likelihood of damage to tools.

So then the question is - how likely if differential sticking on wireline which will push us to sample on pipe again? If we’re unfortunate to have a zone with high permeability and lower pressure than our main reservoirs then it could very well happen again. If the root cause is mud design and filter cake building up then it’s also possibly still likely.

I’m just surprised that they seem to be doing so much damage to the tools on pipe. This method is used to log horizontal wells where you’d think scraping along the side of the well would be a lot worse.

I’d also be suprised if there wasn’t a contingency plan to complete all sampling on wireline, regardless of whether we experience differential sticking of the cable. So long as the tool itself isn’t getting stuck - why would they not just run in over the cable with the fishing tool to free the cable at the location of differential sticking (not run all the way down to connect to the tool). Then rope up with the wireline to the next station once the cable is free and keep doing this from the bottom up? The sticking is obviously not bad enough to affect things while the wireline cable is moving.