Starter guide
Basic Sagan Operations

All commands and simple operations (e.g. data import/save etc) function the same as in Splicer (see splicer guide). The default log data import format is the same as data files downloaded from the web from http://www.ldeo.columbia.edu/BRG/ODP/ODP/CLIP/download.html.

After opening core and log data sets, there are two ways to map core data into the log data, automatically and manually.

1) Automatically: must be done before any manual ties are chosen

In the Process menu choose
Process
->Core-Log Auto Correlate…

A “Core-Log Depth Matching” dialog window will appear (see figure 1)

The autocorrelation routine will calculate the correlation matrix between core and log data for a user defined set of core data compressions and secular log data adjustments. Since the mcd depth scale is usually expanded by ~10% the default compression window (95%-85%, 0.5% steps) is a good starting point. The log adjustment corrects for offsets between drillers and logging depths which are commonly less than a couple of meters.

Click on the Hole(s) you wish to correlate with the log data (usually the Hole you logged in) and click in the “Calculate optimal core-log depth match” button to generate the cross-correlation matrix.

You can scroll through the correlation choices with the up/down arrows at the lower right.

Apply the compression and log adjustment by clicking the “Apply” button at the bottom of the dialog window.

**Hint** This routine will apply one compression factor to all core data and is a good starting point but will not provide a meter scale depth map for core-log integration. Manual ties can be added to refine the core log integration.

2) Manually: apply any number of tie points to map (stretch/compress) the core data to the log reference.

Double click on the core you want to tie to the log. The core will appear in the right hand window next to the log curve.
To choose a tie point on the core click on the point with the middle mouse button.
To choose the equivalent point on the log reference curve click on the log curve with the right mouse button. The core will project onto the log curve and the cross correlation between the two curves within a user defined window appears to the far right of the Sagan window. Hold down the right mouse button and slide up and down with the mouse to assess different matches.

To add the tie to the tie-list click “Add tie to list”

Choose more tie points the same way until you have as many tie points as you wish for the core. Then click the “Apply Ties” button to apply the ties to the chosen core.

To save your ELD table (your table of core-log tie points)
In the File menu: File
-> Save
->Equivalent Log Depth Table…

To save your data files with MBSF, MCD, and ELD depth scales
In the File menu: File
-> Save
->Core data mbsf->[mcd]->eld