JNTU
JNTU B.Tech III WELL LOGGING Previous Question Paper (November/December - 2017 - R15)
Note: This question paper contains two parts A and B. Part A is compulsory which carries 25 marks. Answer all questions in Part A. Part B consists of 5 Units. Answer any one full question from each unit. Each question carries 10 marks and may have a, b, c as sub questions.
Part A
Discuss limitation of cased hole logging operations.
Answer
Cased hole logging is limited by the presence of steel casing and cement, which significantly attenuate signals for many tools. Additionally, it cannot measure formation resistivity directly, and the presence of multiple casing strings or heavy completion fluids can further degrade data quality and tool response.
Which log will assist in determining borehole diameter and how?
Answer
The Caliper log is used to determine borehole diameter. It utilizes mechanical arms or acoustic sensors that extend to contact the borehole wall; as the tool moves, the displacement of these arms is converted into a continuous record of the hole diameter versus depth.
Discuss the advantages of micro-resistivity log.
Answer
Sign in to view the complete answer paper.
State major advantages and limitations of induction tool.
Answer
Sign in to view the complete answer paper.
What are synthetic seismograms?
Answer
Sign in to view the complete answer paper.
Name the logs which can be used to determine porosity of the rocks.
Answer
Sign in to view the complete answer paper.
What is neutron decay time log?
Answer
Sign in to view the complete answer paper.
Discuss the log which can be utilized to correlate the relative position of casing string joints.
Answer
Sign in to view the complete answer paper.
What will you identify through sonic-density cross plots?
Answer
Sign in to view the complete answer paper.
Discuss limitations and advantages of coring analysis.
Answer
Sign in to view the complete answer paper.
Part B
How borehole environment will affect the interpretation of the logs?
Answer
Sign in to view the complete answer paper.
Discuss major components of well logging unit and logging setup.
Answer
Sign in to view the complete answer paper.
How does temperature and pressure affect the gamma ray log?
Answer
Sign in to view the complete answer paper.
Discuss major attributes of SP log and its limitations.
Answer
Sign in to view the complete answer paper.
Write principle, limitations and application of caliper tool.
Answer
Sign in to view the complete answer paper.
State major advantages of focused resistivity tools over conventional resistivity tools.
Answer
Sign in to view the complete answer paper.
Differentiate between effective and total porosity. Also, write the correlation between effective and total porosity.
Answer
Sign in to view the complete answer paper.
Determine true resistivity with given data: formation water resistivity = 15 ohm, cementation exponent = 1.8, Water saturation = 20%, Saturation exponent = 2; porosity = 25%
Answer
Sign in to view the complete answer paper.
Discuss advantages, principle, and limitations of density log.
Answer
Sign in to view the complete answer paper.
How do we identify porosity of interbeded shale-sandstone formation?
Answer
Sign in to view the complete answer paper.
What are the environmental corrections associated with density log?
Answer
Sign in to view the complete answer paper.
Differentiate between primary and secondary porosity of the formation.
Answer
Sign in to view the complete answer paper.
Which log can be used to determine fluid saturation behind the casing and How?
Answer
Sign in to view the complete answer paper.
Why do we run CBL after casing job or prior to any fracturing job?
Answer
Sign in to view the complete answer paper.
Explain basic principle on which NMR tool operates.
Answer
Sign in to view the complete answer paper.
Discuss the advantages and limitations of flow meter logs.
Answer
Sign in to view the complete answer paper.
State various mechanical properties of rocks and their significance in fracturing jobs.
Answer
Sign in to view the complete answer paper.
Discuss various direct methods used in formation evaluation.
Answer
Sign in to view the complete answer paper.
Classify various well logging techniques used in exploration phase.
Answer
Sign in to view the complete answer paper.
Discuss advantages of various cross plots.
Answer
Sign in to view the complete answer paper.