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| *#Depth shifting traces against each other. To do this, the user visually compares base and unshifted traces, marks corresponding data points ([[:file:log-analysis-applications_fig1.png|Figure 1]]), and then shifts the off-depth data to the base trace depths. | | *#Depth shifting traces against each other. To do this, the user visually compares base and unshifted traces, marks corresponding data points ([[:file:log-analysis-applications_fig1.png|Figure 1]]), and then shifts the off-depth data to the base trace depths. |
| *#Correct for true vertical depth (TVD), true vertical thickness (TVT), and/or true stratigraphic thickness (see [[Preprocessing of logging data]]). | | *#Correct for true vertical depth (TVD), true vertical thickness (TVT), and/or true stratigraphic thickness (see [[Preprocessing of logging data]]). |
− | * Baseline the spontaneous potential (SP). Interactively flattening the SP to a shale baseline at a single value ([[:file:log-analysis-applications_fig2.png|Figure 2]]) allows the user to look at SP values quantitatively in order to calculate water resistivity (''R''<sub>w</sub>) and estimate shale content. | + | * Baseline the [[Basic open hole tools#Spontaneous potential|spontaneous potential (SP)]]. Interactively flattening the SP to a shale baseline at a single value ([[:file:log-analysis-applications_fig2.png|Figure 2]]) allows the user to look at SP values quantitatively in order to calculate water resistivity (''R''<sub>w</sub>) and estimate shale content. |
| * Convert data scales (both ways): conductivity to resistivity, raw data to porosities, neutron porosities to a different matrix, metric to English depth units, percent to decimal, and so on. | | * Convert data scales (both ways): conductivity to resistivity, raw data to porosities, neutron porosities to a different matrix, metric to English depth units, percent to decimal, and so on. |
| * Data normalization. This procedure assumes the values in an individual data trace are credible but require some modification. This involves modifying data values with an atypical distribution and/or range to a “normal” distribution and range (see [[:file:log-analysis-applications_fig3.png|Figure 3]] and discussion of histograms). Proper normalization must first account for borehole conditions during each run, ''and'' geological changes taking place across a wider geographic area. Normalization is accomplished by applying the equation: | | * Data normalization. This procedure assumes the values in an individual data trace are credible but require some modification. This involves modifying data values with an atypical distribution and/or range to a “normal” distribution and range (see [[:file:log-analysis-applications_fig3.png|Figure 3]] and discussion of histograms). Proper normalization must first account for borehole conditions during each run, ''and'' geological changes taking place across a wider geographic area. Normalization is accomplished by applying the equation: |