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Hi everybody!

I'm new here!

The question is: How can I weigh the importance to run conventional coring vs sidewall coring. OBM and WBM.
I repute that the SWC in OBM is still a good choice and surely less expensive buit of course we need to see also the total section and laminations. What are your thought on weighting this decision?

I always go for conventional coring, as such a core will benefit all disciplines and will give you the opportunity to run the required tests and get a full section preserved for future use, while SWC is not always successful, and mostly gives small plugs and is not suitable for SCAL tests. If no conventional core is possible then SWC might give an idea of the reservoir properties, but cores are very useful and, I feel, often neglected.

I second this!

Conventional core is always the best choice for data acquisition (given that you have made strong justification to spend certain amount of money; eg. proven reservoir and reserves or decent prospect). SWC may or may not be successful during their coring (tool problem, retrieval problem, etc), and it's usefulness for tests is limited (eg porosity and perm values could be distorted due to the cores usually representing only a small (random) part of the succession). However SWC is cheaper, and does have one BIG plus point - you're able to easily take sample points throughout your hole (if you require).

You are both right but I advise you use rotary sidewall coring you can avoid the distortions and other negative effects. Of course this all depends on the strength of your rock, economics and technical feasibility. Certainly a conventional coring must be justified by a large set of data (that can be correlated to) and the need for detailed stratigraphic and petrophysical studies.