Geology/Mud log analysis
QUESTION: Dear Sir,
how you interpret * Mud log analysis * ? what parameter you look in this Log ?
ANSWER: Waqar Ahmed,
Thanks for the question. Mud log is made during drilling of the well so it should contain drilling as well as geological information about the well being drilled or already drilled. The formations being drilled are continuously analyzed under microscope for lithology and shows (oil and gas). You can expect anything regarding drilling, like, lithological description, formation tops, oil or gas shows, mud weight, mud properties, depth, Swab and surge, WOB, ROP, RPM, SPP, HL, Torque etc.
Can you please elaborate your motive of interpretation of mud log?
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QUESTION: thanks Sir
Sir how Drilling Parameter ( WOB, ROP, RPM, SPP, HL, Torque etc. ) is Altered with Drilling ? I mean to say Drilling behavior with respect to Drilling Parameter...
Q:-2 What you got from analysis of mud-log while all the parameter and behaviors is given in log ?
ANSWER: Waqar Ahmed,
I think it would be more beneficial if you read the following links before trying to understand what mud log gives you.
WOB = Weight on bit
ROP = Rate of penetration
RPM = rotation per min
SPP = Stand pipe pressure
HL = Hook load
These are the drilling parameters which are optimized according to the type of formation being drilled. On mud log you can observe where your reservoirs are, what is their lithology, are they giving encouraging results in terms of hydrocarbons, is top seal present, is there any repetition due to faulting, what drilling problems were encountered and how they were cured, what mud weight was used while drilling, how much days were spent on drilling, logging, cementing, testing, where are your casing shoes, information about casing, well tops etc. You can prognoses which formations you might penetrate while drilling an exploratory well in the region on the basis of mud log of the adjoining well.
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QUESTION: thanks for sending the attachment .
What is ROP Behavior in Sand , Clay ,Shale , silt and corbonats .
ROP depends upon drilling parameters and type of drilling bit. I have seen good ROP in sandstone as compared to carbonates. PDC (polycrystalline ddiamond bit) is used for fast drilling, if you optimise drilling parameters it can give good performance in shale and clay formations but bit balling is the major risk if it doesn't happen you can get very good ROP in shales as well.