Most respectfully it stated that i am fresh graduate student of Geology i had no knowledge about mud logging job ,his responsibilities during rig operation . Sir if it possible than share some knowledge about above . i am very thankful for this kind act.
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Mud logging is the technique in which a geologist who sits on a drilling wellsite collects rock cutting and after washing, removing drilling mud, describe it in an orderly geological manner and prepare a log (log has several columns) against depth which shows at the description of the lithologies at the extreme right hand side and the lithologies on the left hand side column (in percent as mudlogger examined under the microscope ) and cumulative or interpreted lithologies in another column) oil and gas shows are also required to be added in one of the columns.
The columns distribution is not fixed as the format of the mud log varies from company to company.
So, we can say that mudlogger is a geologists who sits at the wellsite and observed and record drilling and geology of the well and prepare a paper where all the observed information is plotted.
Mud loggers are usually take help of a unit which housed several sophisticated electronic devices controlled by computers that help measures and record various drilling and geological parameters.
All mud logging units are equipped with Total gas detectors and gas chromatograph, which records total gas and fraction of the gas contents such as methane, butane, iso-butane, etc. Gas equipments are essential part of the mud logging unit.
The rate of penetration (ROP)is a very fundamental parameters that needs to be monitored through a instruments known as geolograph which measures the time of penetration of bit or drilling rate. The slower drilling rates are when drilling harder rocks such as limestone, Anhydrite and igneous rocks. Shale and sandstone are generally drilled with relative ease and quickly.
What I have described above is the basic function of any mudlogger but these days the role of a mudlogger has been highly diversified.
A mud log image is attached
I started my career as a mudlogger as well and when I completed my Geology education I was not aware about it as well. I wish that new graduates should be adequately versed and trained with mud logging while studying .
Hope this answer may be helpful.
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