Post on 24-Jan-2018
Contents Introduction
Borehole Environment
Types of Well logging
Types of Electrical Well logging
Resistivity Method
Self Potential method
Induction Logging
Conclusion
References
Introduction• Well Logging involves measuring the physical
properties of surrounding rocks with a sensor located in a borehole. The record of measuring as a function of depth is called as well logging.
Borehole Environment
Types of Well logging
Well Logging
1) Electrical Well logging
2) Radioactivity Well logging
3) Sonic Well logging
4) Miscellaneous well logging
Types of Well logging
Well Logging
1) Electrical Well logging
We used to measure lithological variations in borehole by measuring their electrical properties.
It has been observed that in a borehole, the electrical potential varies according to the nature of the beds traversed.
Electrical Well logging
Electrical
Well Logging
1) Resistivity Method
2) Self Potential method
3) Induction Logging
Electrical Well logging
Electrical
Well Logging
1) Resistivity Method
It works by characterizing the rock or sediment in a
borehole by measuring its electrical resistivity.
In the Sedimentary rocks most of the minerals are non-conductors (Silicates and Carbonates), but presence of water in the pore spaces can conduct electricity.
In Metamorphic and Igneous rocks certain minerals can contribute their conductivity.
Resistivity Method
Resistivity
Method
Normal and lateral Log
Microlog
Laterolog
Microlaterolog
Proximity log
Resistivity Method
Resistivity
Method
Normal and lateral Log
2) Laterolog
3) Microlog
4) Microlaterolog
5) Proximity log
The standard normal configuration The standard lateral configuration
Resistivity Method
Resistivity
Method
Normal and lateral Log
Microlog
Resistivity Method
Resistivity Method
Resistivity
Method
Normal and lateral Log
Microlog
Laterolog
The Laterolog configuration
N
M
C0
Working Principal of Laterolog
N
M
C0
C2'
C1'
C2
C1
Resistivity Method
Resistivity
Method
Normal and lateral Log
Laterolog
Microlog
Microlaterolog
Resistivity Method
Resistivity
Method
Normal and lateral Log
Laterolog
Microlog
Microlaterolog
Proximity log
Electrical Well logging
Electrical
Well Logging
Resistivity Method
The determination of resistivity for formations is essential to determination of saturation mainly of the hydrocarbon.
True formation resistivity and flushed zone resistivity.
Mud filtrate Invasion profile.
Electrical Well logging
Electrical
Well Logging
Resistivity Method
Self Potential Method
Cl¯
Na⁺
Cl¯
Na⁺
Electrical Well logging
Electrical
Well Logging
Resistivity Method
Self Potential Method
To delineate porous and permeable reservoir rocks
To determine bed boundaries and bed thickness
To evaluate the formation water resistivityTo estimate the fraction of clay.Correlation of permeable beds
Electrical Well logging
Electrical
Well Logging
Resistivity Method
Self Potential method
Induction Logging
Fe, Mg richbody
ConclusionWell logging is the detailed survey, conducted after the location
for drilling is fixed based on the other preliminary geological and geophysical surveys.
In the normal resistivity logging method, if the thickness of the bed is less than the separation between AM, then we will get reverse graph.
In the resistivity well logging method we use our own source but in the case of SP method we use natural current.
Proximity well logging is use to determine the density of the reserves.
Books:- Philip Kearey, Michael Brooks, Ian Hill (2002), An Introduction to
Geophysical Exploration, Third Edition, Blackwell Science Ltd, Pp 236-244
W.M. Telford, L.P. Geldart, R.E. Shrriff (1990), Applied Geophysics, Second Edition, Cambridge University Press, Pp 645-658
Darwin V. Ellis & Julian M. Singer (2007), Well Logging for Earth Scientists, Second Edition, Springer. Pp 41-59
Websites:- http://www.greatgeophysics.com/logginginfo.html
http://en.wikipedia.org/wiki/Well_logging
http://petrofed.winwinhosting.net/upload/IAI/17-20mar10/WellLoggingTech.pdf
http://petrowiki.org/Electrode_resistivity_devices