Page 42 - Basic Well Log Analysis for Geologist
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BASIC RELATIONSHIPS OF WELL LOG INTERPRETATION
Figure 9. Because resistivity varies with changes in temperature. you must adjust before calculation. Use the chart on the opposite
page.
Courtesy. Schlumberger Well Services.
Copyright 1972, Schlumberger.
Given: Resistivity of drilling mud (R,,) equals 1.2 at 75°F. Formation temperature (T;) = 160°.
Procedure:
1. Locate the resistivity value, |.2, on the scale at the bottom of the chart.
No Follow the vertical line up to a temperature value of 75°F (point A on the chart).
‘nm Follow the diagonal line (constant salinity) to where it intersects a temperature value of 160°F (point B on the
chart).
4. From point B, follow the vertical line to the scale at the bottom. and find a resistivity value of 0.56.
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