Geology 449-University of Calgary

Petrophysical Techniques; Geology/Geophysics 449

Disclaimer: While every reasonable effort is made to ensure that the information provided is accurate, no guarantees for the currency or accuracy of information are made. It takes several proof readings and rewrites to bring the quiz to an exceptional level. If you find an error, please contact me as soon as possible. Please indicate the question ID-Number or description because server may randomize the questions and answers.

Questions on Petrophysical Log Interpretation will not appear in the following exam. Log questions are published under a separate section.

Go to: Midterm II | Well Log Interpretation

Geology (GLGY 449-UCAL) Midterm I

Some questions have hints and explanations. Click Start to begin.
Start

Congratulations - you have completed Geology (GLGY 449-UCAL) Midterm I.

You scored %%SCORE%% out of %%TOTAL%%.

Your performance has been rated as %%RATING%%


Your answers are highlighted below.
Return
Shaded items are complete.
12345
678910
1112131415
1617181920
2122232425
2627282930
3132333435
3637383940
4142434445
End
Return

Credits: Based on the excellent class notes provided by, Dr. Rudi Meyer during Fall 2014.
FAQ | Report an Error

If you are a company or an organization willing to donate copies of well logs, please contact me. I really appreciate your contributions.


Type
of tool
DOI Resolution Used for… Processes Notes
Caliper NA NA -Borehole size
and shape
Spring loaded
arms
2 arm = diameter
4 arm = shape, orientation
Gamma
Ray
10 – 15 cm ~40 cm -Lithology(vol. Shale/Sand often due to high K), geosteering,
facies, depth control
-Photoelectric effect (dom)
-Compton scattering
-Pair production
-Scintillation counter + photomultiplier
High (right kick):
-Shale line
-Organic content
-K-Feldspars
Low (left kick):
-Clean sand
-Carbonates
-Clean coals
Spectral
Gamma Ray
    -Radioactive anomalies
-Clay types
-Volume of shale(clay)
-Same as GR, but much better/larger scintillator  
Density
& Photoelectric Factor
< 10 cm 11 – 40 cm -Porosity, general lithology, min ids    
Neutron 15 – 25 cm ~50 cm -Fluid, porosity, density, cross-over gas effect
-Meassures porosity; used for calulating density
Hydrogen High (left kick):
-Shales and coals
Low (right kick):
-Gas breaing fm./rocks
Use Dphi & Nphi chart
*Decreased with increased permeability
Spontaneous
Potential
Depends Depends -Permeability(even small), lithology, facies, shale volume(not
so much)
Natural potential differences between fms. caused by:
-Diffusion
-Mambrane or shale potential
Important:
-Salinity of drilling fluid to fm.
-Conductive drilling fluid
-Constrasting permeability in adj. beds
-Surface electrode(earth)
No absolute scale(relatove +/-)
Positive kick (relative):
-Clean sand or sand stone, shaly sand
Negative kick (relative):
-Shale
*Decreased with increased permeability